docs: mark Phase 11 (Great Cycle) complete in PROGRESS.md + IMPLEMENTATION-PLAN.md

Phase 11 summary: 51 new tests (562 total), 7 new/modified files.
Core systems: GreatCycleState, RunTrace, WorldTrace ECS, RenewalScene,
cycle narrative, Mycelium maturation, CradleScene/UIScene/GameScene integration.

Co-authored-by: Cursor <cursoragent@cursor.com>

.cursor/rules/agent-workflow.mdc

@@ -12,26 +12,29 @@ For every task, follow this sequence:
 3. **Implementation** — write code to make tests pass
 4. **Verify** — `npm run test:run` for logic, Playwright screenshot for visuals
 5. **Commit** — `git add -A && git commit` after each successful step
+6. **Push** — `git push` after every commit (never accumulate unpushed commits)
 
-## Commit Discipline
+## Commit & Push Discipline
 - Commit after EVERY successful step (tests green or visual verified)
+- Push immediately after every commit — code must always be on remote
 - Small, focused commits — one concern per commit
-- Never accumulate uncommitted work across multiple tasks
+- Never accumulate uncommitted or unpushed work across multiple tasks
 - Commit message format: concise "what + why" in English
 
 ## Visual Verification
 After ANY visual change:
 1. Ensure dev server is running (`npm run dev`)
 2. Navigate to `http://localhost:5173`
-3. Take screenshot to see result
+3. Take screenshot to `screenshots/` folder (gitignored)
 4. Check browser console for errors
 5. Fix issues before committing
 
 ## After Completing a Task
 1. Verify it works (test or screenshot)
 2. Commit immediately
-3. Update `PROGRESS.md` — mark task complete
+3. Push immediately (`git push`)
-4. Check `IMPLEMENTATION-PLAN.md` for what's next
+4. Update `PROGRESS.md` — mark task complete
+5. Check `IMPLEMENTATION-PLAN.md` for what's next
 
 ## Code Standards
 - TypeScript strict mode — no `any`, no unsafe `as` casts

.gitignore

@@ -3,3 +3,5 @@ dist/
 .vite/
 *.local
 .DS_Store
+screenshots/
+.playwright-mcp/

IMPLEMENTATION-PLAN.md

@@ -122,7 +122,7 @@
 
 ---
 
-## Phase 5: Creatures & Ecology
+## Phase 5: Creatures & Ecology ✅
 
 **Цель:** Живая экосистема в Каталитических Пустошах  
 **Зависимости:** Phase 2, Phase 3
@@ -145,7 +145,7 @@
 
 ---
 
-## Phase 6: Run Cycle
+## Phase 6: Run Cycle ✅
 
 **Цель:** Полный рогалик-цикл: рождение → смерть → перерождение  
 **Зависимости:** Phase 3, Phase 4, Phase 1
@@ -172,7 +172,7 @@
 
 ---
 
-## Phase 7: Mycelium
+## Phase 7: Mycelium ✅
 
 **Цель:** Подземная сеть, связывающая раны  
 **Зависимости:** Phase 6
@@ -195,7 +195,7 @@
 
 ---
 
-## Phase 8: First Archont — Ouroboros
+## Phase 8: First Archont — Ouroboros ✅
 
 **Цель:** Первый босс-бой (головоломка, не рефлексы)  
 **Зависимости:** Phase 5, Phase 6
@@ -238,9 +238,9 @@
 
 | Фаза | Содержание |
 |-------|-----------|
-| Phase 9 | +2 биома (Кинетические Горы, Вердантовые Леса), +20 элементов, +100 реакций |
+| Phase 9 ✅ | +2 биома (Кинетические Горы, Вердантовые Леса), +20 элементов, +100 реакций |
-| Phase 10 | +3 школы (Механик, Натуралист, Навигатор), принципы физики и биологии |
+| Phase 10 ✅ | +3 школы (Механик, Натуралист, Навигатор), принципы физики и биологии |
-| Phase 11 | Великий цикл (7 ранов): следы между ранами, Великое Обновление |
+| Phase 11 ✅ | Великий цикл (7 ранов): следы между ранами, Великое Обновление |
 | Phase 12 | +3 Архонта (Спора Прайма, Энтропа, Когнитон) |
 | Phase 13 | Оставшиеся биомы + школы + существа |
 | Phase 14 | Сердце Синтеза (финальный регион), нарратив |

PROGRESS.md

@@ -1,7 +1,7 @@
 # Synthesis — Development Progress
 
 > **Last updated:** 2026-02-12  
-> **Current phase:** Phase 3 ✅ → Ready for Phase 4
+> **Current phase:** Phase 11 ✅ → Great Cycle Complete
 
 ---
 
@@ -48,23 +48,119 @@
 - [x] 3.7 Minimap — canvas-based 160x160 overview, viewport indicator, border (`src/world/minimap.ts`)
 - [x] Unit tests — 21 passing (`tests/world.test.ts`)
 
+### Phase 4: Player Systems ✅
+- [x] 4.1 Player entity + WASD controller (`src/player/input.ts`, `src/player/collision.ts`, `src/player/spawn.ts`, `src/player/factory.ts`)
+- [x] 4.2 Inventory — weight-based, element stacking, AMU mass from registries (`src/player/inventory.ts`)
+- [x] 4.3 Element collection from world objects — resource entities, proximity interaction, E key (`src/player/interaction.ts`, `src/world/resources.ts`)
+- [x] 4.4 Crafting — chemistry engine integration, inventory consume/produce, condition checking (`src/player/crafting.ts`)
+- [x] 4.5 Projectile system — throw elements toward mouse, lifetime + tile collision (`src/player/projectile.ts`)
+- [x] 4.6 Quick slots — 4 hotkeys, auto-assign on pickup, active slot for throw (`src/player/quickslots.ts`)
+- [x] 4.7 HUD — UIScene overlay: health bar, quick slots, inventory info, controls hint (`src/scenes/UIScene.ts`)
+- [x] Unit tests — 39 player + 28 inventory + 12 interaction + 11 crafting + 13 projectile + 15 quickslots + 8 UI = 126 tests (222 total)
+
+### Phase 5: Creatures & Ecology ✅
+- [x] 5.1 Creature data — 3 species: Crystallids, Acidophiles, Reagents (`src/data/creatures.json`)
+- [x] 5.2 AI behavior — FSM: idle → wander → feed → flee → attack (`src/creatures/ai.ts`)
+- [x] 5.3 Metabolism — energy drain, feeding from resources, starvation damage (`src/creatures/metabolism.ts`)
+- [x] 5.4 Population dynamics — counting, reproduction, initial spawning (`src/creatures/population.ts`)
+- [x] 5.5 Life cycle — egg → youth → mature → aging → natural death (`src/creatures/lifecycle.ts`)
+- [x] 5.6 Interaction — projectile collision (armor), observation, creature→player melee (`src/creatures/interaction.ts`)
+- [x] 5.7 Ecosystem test — populations fluctuate, don't die out (`tests/ecosystem.test.ts`)
+- [x] 5.8 GameScene integration — all creature systems in update loop, debug overlay
+- [x] ECS components: Creature, AI, Metabolism, LifeCycle (`src/ecs/components.ts`)
+- [x] Species registry with string/numeric ID lookup (`src/creatures/types.ts`)
+- [x] Creature factory (`src/creatures/factory.ts`)
+- [x] Unit tests — 51 creature + 16 interaction + 5 ecosystem = 72 tests (293 total)
+
+### Phase 6: Run Cycle ✅
+- [x] 6.1 Spore Cradle — CradleScene: school selection UI, floating spore particles, meta display (`src/scenes/CradleScene.ts`)
+- [x] 6.2 Death trigger — player death → camera fade → DeathScene transition (`src/scenes/GameScene.ts`)
+- [x] 6.3 Death animation — body decomposes into real elements (65% O, 18% C, 10% H...), element labels, Mycelium threads absorbing particles (`src/scenes/DeathScene.ts`)
+- [x] 6.4 Moment Between — WebGL Mandelbrot/Julia hybrid shader with morphing + zoom, canvas fallback for non-WebGL (`src/scenes/FractalScene.ts`)
+- [x] 6.5 Meta-progression — Codex (permanent knowledge), spores (currency), run history, IndexedDB persistence (`src/run/meta.ts`, `src/run/persistence.ts`)
+- [x] 6.6 Run phases — state machine: Awakening → Exploration → Escalation → Crisis → Resolution, auto-advance on timers (`src/run/state.ts`)
+- [x] 6.7 Escalation — creature speed/aggro/damage multipliers, reaction instability, environmental damage at high entropy (`src/run/escalation.ts`)
+- [x] 6.8 Crisis: Chemical Plague — chain reaction poisons atmosphere, progressive player damage, toxic green tint overlay, CaO neutralization mechanics (`src/run/crisis.ts`)
+- [x] 6.9 School: Alchemist — starting kit (H×5, O×5, C×3, Na×3, S×2, Fe×2), chemical equilibrium principle (`src/data/schools.json`)
+- [x] Scene flow: BootScene → CradleScene → GameScene → DeathScene → FractalScene → CradleScene (full loop verified)
+- [x] Texture cleanup for multi-run support (tilemap + minimap textures removed before recreation)
+- [x] Unit tests — 42 run-cycle + 14 escalation = 56 tests (349 total)
+
+### Phase 7: Mycelium ✅
+- [x] 7.1 Mycelium Graph — persistent knowledge network (nodes, edges, deposit/strengthen/query) (`src/mycelium/graph.ts`)
+- [x] 7.2 Fungal Nodes — ECS entities on world map, glowing bioluminescent spots, pulsing animation (`src/mycelium/nodes.ts`)
+- [x] 7.3 Knowledge Recording — deposit run discoveries into Mycelium (auto on death + manual at nodes) (`src/mycelium/knowledge.ts`)
+- [x] 7.4 Knowledge Extraction — memory flashes from past runs, weighted by node strength, Russian text templates (`src/mycelium/knowledge.ts`)
+- [x] 7.5 Mycosis — visual distortion (tint overlay) on prolonged fungal node contact, reveals hidden info at threshold (`src/mycelium/mycosis.ts`)
+- [x] 7.6 Spore Shop — Cradle integration: spend spores for starting bonuses (extra health, elements, knowledge boost) (`src/mycelium/shop.ts`)
+- [x] ECS component: FungalNode (nodeIndex, glowPhase, interactRange) (`src/ecs/components.ts`)
+- [x] Data: mycelium config, spore bonuses, memory templates (`src/data/mycelium.json`)
+- [x] MetaState extended with MyceliumGraphData, IndexedDB persistence updated
+- [x] GameScene integration: node spawning, glow rendering, E-key interaction, mycosis overlay, memory flash display
+- [x] CradleScene integration: spore shop UI, Mycelium stats display, purchased effects passed to GameScene
+- [x] Unit tests — 36 passing (`tests/mycelium.test.ts`) (385 total)
+
+### Phase 8: First Archont — Ouroboros ✅
+- [x] 8.1 Ouroboros entity — Boss data JSON, BossData type, Boss ECS component, entity factory (`src/boss/factory.ts`, `src/data/bosses.json`)
+- [x] 8.2 Pattern mechanics — 4-phase cyclical AI: Coil → Spray → Lash → Digest, escalating difficulty (10% faster per cycle, caps at 5), regeneration + armor systems (`src/boss/ai.ts`)
+- [x] 8.3 Arena — circular generated room (21×21 tiles), acid pools, crystal walls, 4 mineral deposits, boss center / player south spawn (`src/boss/arena.ts`)
+- [x] 8.4 Multiple solutions — 3 real-chemistry victory paths: NaOH acid-base neutralization (3× dmg during Spray), direct damage during Digest vulnerability, Hg catalyst poisoning (permanently reduces regen+armor) (`src/boss/victory.ts`)
+- [x] 8.5 Reward — Archont's Memory lore entry in Codex, spore reward (100 base, +50% chemical, +100% catalytic), CodexEntry type extended with 'boss' (`src/boss/reward.ts`)
+- [x] BossArenaScene — full boss fight scene with phase-based attacks (Coil: chase, Spray: rotating acid projectiles, Lash: area sweep, Digest: immobile+vulnerable), boss health bar + phase indicator, victory/death handling (`src/scenes/BossArenaScene.ts`)
+- [x] GameScene integration — Resolution phase completion triggers arena transition, inventory/quickslots/health carried over
+- [x] Scene flow extended: GameScene → BossArenaScene → DeathScene (on death or victory)
+- [x] Unit tests — 70 passing (`tests/boss.test.ts`) (455 total)
+
+### Phase 9: Biome Expansion ✅
+- [x] 9.1 New elements — 20 additional real elements (Li, B, F, Ne, Ar, Ti, Cr, Mn, Co, Ni, As, Br, Ag, I, Ba, W, Pt, Pb, Bi, U) → 40 total
+- [x] 9.2 New compounds — 39 new compounds (acids, salts, oxides, organics) → 64 total
+- [x] 9.3 New reactions — 85 new reactions (synthesis, combustion, acid-base, redox, decomposition, replacement) → 119 total
+- [x] 9.4 Kinetic Mountains biome — physics/mechanics themed: chasms, gear floors, magnetic fields, steam vents, ore deposits
+- [x] 9.5 Verdant Forests biome — biology/ecology themed: bogs, toxic blooms, ancient trees, mycelium carpet, herb patches
+- [x] 9.6 Biome selection — CradleScene biome picker UI, biomeId passed to GameScene, generic world generator
+- [x] 9.7 New creatures — 6 species: Pendulums/Mechanoids/Resonators (mountains), Symbiotes/Mimics/Spore-bearers (forests)
+- [x] 9.8 World generator genericized — tile lookup by property (interactive/resource) instead of hardcoded names
+- [x] Chemistry types extended — `actinide` element category for Uranium
+- [x] Species types extended — `biome` field, `SpeciesId` enum expanded (0–8)
+- [x] GameScene filters creatures by selected biome
+- [x] Unit tests — 32 new tests (487 total)
+
+### Phase 10: Schools ✅
+- [x] 10.1 SchoolData type extended — `bonuses`, `unlockCondition`, `ResolvedSchoolBonuses` interface (`src/run/types.ts`)
+- [x] 10.2 3 new schools — Mechanic, Naturalist, Navigator with real science principles (`src/data/schools.json`)
+- [x] 10.3 School unlock system — data-driven conditions: elements_discovered, creatures_discovered, runs_completed (`src/run/meta.ts`)
+- [x] 10.4 School bonuses resolver — `getSchoolBonuses()` returns complete multiplier set with defaults (`src/run/meta.ts`)
+- [x] 10.5 Bonus integration — movement speed (Navigator), projectile damage (Mechanic), creature aggro range (Naturalist), reaction efficiency (Alchemist)
+- [x] 10.6 CradleScene updated — all 4 schools displayed, locked schools grayed out with lock icon + unlock hint, bonus indicators shown
+- [x] 10.7 System signatures updated — `playerInputSystem`, `aiSystem`, `creatureProjectileSystem` accept optional multiplier params
+- [x] Unit tests — 24 new tests (511 total): school data, unlock conditions (cumulative, multi-school, persistence), bonuses per school
+
+### Phase 11: Great Cycle ✅
+- [x] 11.1 GreatCycleState types — CycleTheme enum, RunTrace, GreatCycleState, CycleWorldModifiers (`src/run/types.ts`)
+- [x] 11.2 Great Cycle engine — cycle tracking, theme resolution, trace recording, renewal, world modifiers (`src/run/cycle.ts`)
+- [x] 11.3 MetaState extended — `greatCycle` field, persistence updated, RunState extended with biomeId/worldSeed/deathPosition
+- [x] 11.4 Run trace recording — death position, school, biome, discoveries saved per run via `applyRunResults`
+- [x] 11.5 World trace placement — WorldTrace ECS component, death site markers (dark red), discovery markers (blue), glow animation (`src/world/traces.ts`)
+- [x] 11.6 Cycle narrative data — 6 themes with Russian lore fragments, cradle quotes, renewal messages (`src/data/cycle-narrative.json`)
+- [x] 11.7 RenewalScene — special scene between great cycles: Mycelium particles, staged text reveals, cycle transition, lore, maturation display (`src/scenes/RenewalScene.ts`)
+- [x] 11.8 Mycelium maturation — strengthens all nodes on renewal, caps at 1.0, cumulative across cycles
+- [x] 11.9 CradleScene integration — "Великий Цикл N: Тема | Ран X/7", narrative quote per theme
+- [x] 11.10 UIScene integration — cycle info bar + run phase display below health
+- [x] 11.11 GameScene integration — world trace spawning, trace glow rendering, death position recording, cycle info to registry
+- [x] 11.12 Scene flow extended — Fractal → RenewalScene (on 7th run) → Cradle, or Fractal → Cradle (normal)
+- [x] Unit tests — 51 new tests (562 total): cycle init, themes, traces, advancement, renewal, world modifiers, narrative data, full integration
+
 ---
 
 ## In Progress
 
-_None — ready to begin Phase 4_
+_None — Phase 11 complete_
 
 ---
 
-## Up Next: Phase 4 — Player Systems
+## Up Next: Phase 12+
 
-- [ ] 4.1 Player entity + WASD controller
+_(See IMPLEMENTATION-PLAN.md for Beyond Vertical Slice)_
-- [ ] 4.2 Inventory (weight-based, element stacking)
-- [ ] 4.3 Element collection from world objects
-- [ ] 4.4 Crafting (chemistry engine integration)
-- [ ] 4.5 Projectile system (throw elements/compounds)
-- [ ] 4.6 Quick slots (1-2-3-4 hotkeys)
-- [ ] 4.7 HUD (UIScene: health ring, inventory bar, element info)
 
 ---
 
@@ -82,3 +178,11 @@ None
 | 2 | 2026-02-12 | Phase 1 | Chemistry engine: 20 elements, 25 compounds, 34 reactions, engine with O(1) lookup + educational failures, 35 tests passing |
 | 3 | 2026-02-12 | Phase 2 | ECS foundation: world + time, 5 components, movement + bounce + health systems, Phaser bridge (polling sync), entity factory, GameScene with 20 bouncing circles at 60fps, 39 tests passing |
 | 4 | 2026-02-12 | Phase 3 | World generation: simplex noise (seeded), 80x80 tilemap with 8 tile types, Catalytic Wastes biome, camera WASD+zoom, minimap with viewport indicator, 21 tests passing (95 total) |
+| 5 | 2026-02-12 | Phase 4 | Player systems: WASD movement + tile collision, weight-based inventory, resource collection, crafting via chemistry engine, projectile throw, 4 quick slots, UIScene HUD overlay (health bar, slots, inventory), 126 new tests (222 total) |
+| 6 | 2026-02-12 | Phase 5 | Creatures & Ecology: 3 species (Crystallid/Acidophile/Reagent), FSM AI (idle/wander/feed/flee/attack), metabolism (energy drain/feeding/starvation), life cycle (egg→youth→mature→aging→death), population dynamics, projectile-creature collision with armor, creature→player melee, ecosystem simulation test, 72 new tests (293 total) |
+| 7 | 2026-02-12 | Phase 6 | Run Cycle: full roguelike loop (Cradle→Game→Death→Fractal→Cradle), school selection (Alchemist), meta-progression (Codex/spores/IndexedDB), run phases with auto-advance, escalation effects (creature aggression/env damage), Chemical Plague crisis with neutralization, death animation (real body composition), WebGL fractal shader, 56 new tests (349 total) |
+| 8 | 2026-02-12 | Phase 7 | Mycelium: persistent knowledge graph (nodes/edges/strength), fungal node ECS entities with glow animation, knowledge deposit (auto on death + manual at nodes), memory flash extraction (weighted by strength, Russian templates), mycosis visual effect (tint overlay + reveal threshold), spore shop in Cradle (5 bonuses: health/elements/knowledge), MetaState+IndexedDB persistence updated, GameScene+CradleScene integration, 36 new tests (385 total) |
+| 9 | 2026-02-12 | Phase 8 | Ouroboros boss fight: 4-phase cyclical AI (Coil/Spray/Lash/Digest) with escalating difficulty, 3 chemistry-based victory paths (NaOH neutralization, direct damage, Hg catalyst poison), circular arena generator, BossArenaScene with attacks+collision+UI, Archont's Memory lore reward, CodexEntry extended, GameScene Resolution→arena trigger, 70 new tests (455 total) |
+| 10 | 2026-02-12 | Phase 9 | Biome expansion: +20 elements (40 total), +39 compounds (64 total), +85 reactions (119 total), 2 new biomes (Kinetic Mountains + Verdant Forests), biome selection in CradleScene, 6 new creature species (3 per new biome), generic world generator, 32 new tests (487 total) |
+| 11 | 2026-02-12 | Phase 10 | Schools: +3 schools (Mechanic/Naturalist/Navigator), data-driven unlock system (elements/creatures/runs), school bonuses (projectile dmg, movement speed, aggro range, reaction efficiency), CradleScene shows locked schools with hints, system multiplier params, 24 new tests (511 total) |
+| 12 | 2026-02-12 | Phase 11 | Great Cycle: 7-run macro cycles with traces between runs, GreatCycleState (cycle number/theme/traces), RunTrace recording (death position/school/biome/discoveries), WorldTrace ECS entities (death markers + discovery sites with glow), RenewalScene (Mycelium particles/staged text/cycle transition), 6 narrative themes (Awakening→Synthesis) with Russian lore, Mycelium maturation on renewal, CradleScene+UIScene+GameScene cycle display, 51 new tests (562 total) |

src/boss/ai.ts

@@ -0,0 +1,152 @@
+/**
+ * Boss AI System — cyclical phase logic for Archon encounters
+ *
+ * The boss cycles through 4 phases (Coil → Spray → Lash → Digest),
+ * each cycle becoming faster. During Digest, the boss is vulnerable.
+ * Between cycles, the boss regenerates health (self-catalysis).
+ */
+
+import {
+  BossPhase,
+  BOSS_PHASE_COUNT,
+  type BossData,
+  type BossState,
+  type BossPhaseEvent,
+} from './types';
+
+/** Create initial boss state from boss data */
+export function createBossState(boss: BossData): BossState {
+  const initialDuration = getEffectivePhaseDuration(
+    { cycleCount: 0 } as BossState, boss, BossPhase.Coil,
+  );
+
+  return {
+    bossId: boss.id,
+    health: boss.health,
+    maxHealth: boss.health,
+    currentPhase: BossPhase.Coil,
+    phaseTimer: initialDuration,
+    cycleCount: 0,
+    catalystStacks: 0,
+    defeated: false,
+    victoryMethod: null,
+    totalDamageDealt: 0,
+    chemicalDamageDealt: 0,
+    directDamageDealt: 0,
+    catalystDamageDealt: 0,
+  };
+}
+
+/**
+ * Get the effective phase duration, accounting for cycle speedup.
+ * Each completed cycle multiplies duration by phaseSpeedupPerCycle.
+ * Caps at maxCycles to prevent impossibly short phases.
+ */
+export function getEffectivePhaseDuration(
+  state: Pick<BossState, 'cycleCount'>,
+  boss: BossData,
+  phase: BossPhase,
+): number {
+  const baseDuration = boss.phaseDurations[phase];
+  const effectiveCycles = Math.min(state.cycleCount, boss.maxCycles);
+  return baseDuration * Math.pow(boss.phaseSpeedupPerCycle, effectiveCycles);
+}
+
+/**
+ * Get effective armor value, accounting for catalyst poison stacks.
+ * During vulnerable phases: uses armorVulnerable as base.
+ * During normal phases: uses armor as base.
+ * Catalyst stacks reduce armor further.
+ */
+export function getEffectiveArmor(
+  state: BossState,
+  boss: BossData,
+): number {
+  const isVulnerable = boss.vulnerablePhases.includes(state.currentPhase);
+  const baseArmor = isVulnerable ? boss.armorVulnerable : boss.armor;
+  const reduction = state.catalystStacks * boss.catalystArmorReduction;
+  return Math.max(0, baseArmor - reduction);
+}
+
+/**
+ * Get effective regeneration rate, accounting for catalyst poison.
+ * Each catalyst stack permanently reduces regen.
+ */
+export function getEffectiveRegen(
+  state: BossState,
+  boss: BossData,
+): number {
+  const reduction = state.catalystStacks * boss.catalystRegenReduction;
+  return Math.max(0, boss.regenPerSecond - reduction);
+}
+
+/**
+ * Check if the boss is currently in a vulnerable phase.
+ */
+export function isVulnerable(state: BossState, boss: BossData): boolean {
+  return boss.vulnerablePhases.includes(state.currentPhase);
+}
+
+/**
+ * Update boss phase timer and cycle through phases.
+ * Returns events for phase changes, cycle completions, and attacks.
+ *
+ * @param state - Mutable boss state
+ * @param boss - Immutable boss data
+ * @param delta - Time elapsed in ms
+ * @returns Array of events that occurred this tick
+ */
+export function updateBossPhase(
+  state: BossState,
+  boss: BossData,
+  delta: number,
+): BossPhaseEvent[] {
+  if (state.defeated) return [];
+
+  const events: BossPhaseEvent[] = [];
+
+  // Apply regeneration
+  const regen = getEffectiveRegen(state, boss);
+  if (regen > 0) {
+    state.health = Math.min(state.maxHealth, state.health + regen * (delta / 1000));
+  }
+
+  // Count down phase timer
+  state.phaseTimer -= delta;
+
+  // Phase transition
+  while (state.phaseTimer <= 0) {
+    const nextPhase = ((state.currentPhase + 1) % BOSS_PHASE_COUNT) as BossPhase;
+
+    // Cycle completion: when Digest ends (wrapping back to Coil)
+    if (state.currentPhase === BossPhase.Digest) {
+      state.cycleCount += 1;
+      events.push({
+        type: 'cycle_complete',
+        phase: nextPhase,
+        cycleCount: state.cycleCount,
+      });
+    }
+
+    state.currentPhase = nextPhase;
+    const newDuration = getEffectivePhaseDuration(state, boss, nextPhase);
+    state.phaseTimer += newDuration;
+
+    events.push({
+      type: 'phase_change',
+      phase: nextPhase,
+      cycleCount: state.cycleCount,
+    });
+  }
+
+  // Boss attacks during Spray and Lash phases
+  if (state.currentPhase === BossPhase.Spray || state.currentPhase === BossPhase.Lash) {
+    events.push({
+      type: 'boss_attack',
+      phase: state.currentPhase,
+      cycleCount: state.cycleCount,
+    });
+  }
+
+  return events;
+}

src/boss/arena.ts

@@ -0,0 +1,136 @@
+/**
+ * Boss Arena Generator — creates a circular arena for Archon encounters
+ *
+ * The arena is a special room with:
+ * - Circular walkable area surrounded by crystal walls
+ * - Acid pools near the edges (hazards)
+ * - 4 mineral deposits at cardinal positions (for ammo)
+ * - Boss spawns at center, player enters from south
+ *
+ * Uses the same tile index system as the main world generator.
+ */
+
+import type { BossData, ArenaData } from './types';
+import type { BiomeData } from '../world/types';
+
+/** Tile indices matching biomes.json tile order */
+const TILE = {
+  GROUND: 0,
+  SCORCHED_EARTH: 1,
+  ACID_SHALLOW: 2,
+  ACID_DEEP: 3,
+  CRYSTAL_FORMATION: 4,
+  GEYSER: 5,
+  MINERAL_VEIN: 6,
+  BEDROCK: 7,
+} as const;
+
+/**
+ * Generate a circular boss arena.
+ *
+ * @param boss - Boss data (determines arena size)
+ * @param biome - Biome data (for tile size)
+ * @returns Arena data with grid, spawn positions, and resource locations
+ */
+export function generateArena(boss: BossData, biome: BiomeData): ArenaData {
+  const radius = boss.arenaRadius;
+  const diameter = radius * 2 + 1;
+  const centerTile = radius;
+  const tileSize = biome.tileSize;
+
+  // Initialize grid with bedrock (impassable)
+  const grid: number[][] = [];
+  for (let y = 0; y < diameter; y++) {
+    grid[y] = [];
+    for (let x = 0; x < diameter; x++) {
+      grid[y][x] = TILE.BEDROCK;
+    }
+  }
+
+  const resourcePositions: { x: number; y: number }[] = [];
+
+  // Carve circular arena
+  for (let y = 0; y < diameter; y++) {
+    for (let x = 0; x < diameter; x++) {
+      const dx = x - centerTile;
+      const dy = y - centerTile;
+      const dist = Math.sqrt(dx * dx + dy * dy);
+
+      if (dist <= radius - 1) {
+        // Inner arena: walkable ground
+        grid[y][x] = TILE.GROUND;
+
+        // Acid pools ring at 60-75% of radius
+        if (dist > radius * 0.6 && dist <= radius * 0.75) {
+          // Place acid in a pattern (not solid ring — alternating)
+          const angle = Math.atan2(dy, dx);
+          const sector = Math.floor((angle + Math.PI) / (Math.PI / 4));
+          if (sector % 2 === 0) {
+            grid[y][x] = TILE.ACID_SHALLOW;
+          }
+        }
+
+        // Scorched earth ring at 75-90% of radius
+        if (dist > radius * 0.75 && dist <= radius * 0.9) {
+          grid[y][x] = TILE.SCORCHED_EARTH;
+        }
+      } else if (dist <= radius) {
+        // Crystal wall border
+        grid[y][x] = TILE.CRYSTAL_FORMATION;
+      }
+    }
+  }
+
+  // Place 4 mineral deposits at cardinal positions (40% of radius from center)
+  const mineralDist = Math.round(radius * 0.4);
+  const cardinalOffsets = [
+    { dx: 0, dy: -mineralDist },  // North
+    { dx: mineralDist, dy: 0 },   // East
+    { dx: 0, dy: mineralDist },   // South (near player spawn)
+    { dx: -mineralDist, dy: 0 },  // West
+  ];
+
+  for (const offset of cardinalOffsets) {
+    const mx = centerTile + offset.dx;
+    const my = centerTile + offset.dy;
+    if (mx >= 0 && mx < diameter && my >= 0 && my < diameter) {
+      grid[my][mx] = TILE.MINERAL_VEIN;
+      resourcePositions.push({
+        x: mx * tileSize + tileSize / 2,
+        y: my * tileSize + tileSize / 2,
+      });
+    }
+  }
+
+  // Boss spawns at center
+  const bossSpawnX = centerTile * tileSize + tileSize / 2;
+  const bossSpawnY = centerTile * tileSize + tileSize / 2;
+
+  // Player spawns at south edge (80% of radius from center)
+  const playerSpawnX = centerTile * tileSize + tileSize / 2;
+  const playerSpawnY = (centerTile + Math.round(radius * 0.8)) * tileSize + tileSize / 2;
+
+  return {
+    grid,
+    width: diameter,
+    height: diameter,
+    bossSpawnX,
+    bossSpawnY,
+    playerSpawnX,
+    playerSpawnY,
+    resourcePositions,
+  };
+}
+
+/**
+ * Build a set of walkable tile indices for the arena.
+ * Matches the pattern used in the main world's collision system.
+ */
+export function buildArenaWalkableSet(): Set<number> {
+  return new Set([
+    TILE.GROUND,
+    TILE.SCORCHED_EARTH,
+    TILE.MINERAL_VEIN,
+    TILE.GEYSER,
+  ]);
+}

src/boss/factory.ts

@@ -0,0 +1,59 @@
+/**
+ * Boss Entity Factory — creates boss entities in the ECS world
+ *
+ * The boss gets: Position, Velocity, Health, SpriteRef, Boss components.
+ * Rich state (phase, cycle, stacks) is stored in BossState, not ECS.
+ */
+
+import { addEntity, addComponent } from 'bitecs';
+import type { World } from '../ecs/world';
+import {
+  Position,
+  Velocity,
+  Health,
+  SpriteRef,
+  Boss,
+} from '../ecs/components';
+import type { BossData } from './types';
+
+/**
+ * Create a boss entity at the given position.
+ *
+ * @returns Entity ID
+ */
+export function createBossEntity(
+  world: World,
+  boss: BossData,
+  x: number,
+  y: number,
+): number {
+  const eid = addEntity(world);
+
+  // Position
+  addComponent(world, eid, Position);
+  Position.x[eid] = x;
+  Position.y[eid] = y;
+
+  // Velocity (boss controls its own movement via AI)
+  addComponent(world, eid, Velocity);
+  Velocity.vx[eid] = 0;
+  Velocity.vy[eid] = 0;
+
+  // Health
+  addComponent(world, eid, Health);
+  Health.current[eid] = boss.health;
+  Health.max[eid] = boss.health;
+
+  // Visual
+  addComponent(world, eid, SpriteRef);
+  SpriteRef.color[eid] = parseInt(boss.color.replace('#', ''), 16);
+  SpriteRef.radius[eid] = boss.radius;
+
+  // Boss tag
+  addComponent(world, eid, Boss);
+  Boss.dataIndex[eid] = 0; // Index in bosses.json array (only Ouroboros for now)
+  Boss.phase[eid] = 0;     // BossPhase.Coil
+  Boss.cycleCount[eid] = 0;
+
+  return eid;
+}

src/boss/index.ts

@@ -0,0 +1,19 @@
+/**
+ * Boss module — Archon encounters
+ */
+
+export { BossPhase, VictoryMethod } from './types';
+export type {
+  BossData,
+  BossState,
+  BossDamageResult,
+  BossPhaseEvent,
+  ArenaData,
+  BossReward,
+} from './types';
+
+export { createBossState, updateBossPhase, getEffectiveArmor, getEffectiveRegen, isVulnerable, getEffectivePhaseDuration } from './ai';
+export { applyBossDamage, isBossDefeated } from './victory';
+export { generateArena, buildArenaWalkableSet } from './arena';
+export { calculateBossReward, applyBossReward } from './reward';
+export { createBossEntity } from './factory';

src/boss/reward.ts

@@ -0,0 +1,86 @@
+/**
+ * Boss Reward System — Archont's Memory and spore rewards
+ *
+ * Defeating a boss grants:
+ * 1. Spores (currency for meta-progression)
+ * 2. Archont's Memory — a lore entry added to the Codex
+ * 3. Victory flavor based on the method used
+ */
+
+import { VictoryMethod, type BossData, type BossState, type BossReward } from './types';
+import type { MetaState, CodexEntry } from '../run/types';
+
+/**
+ * Calculate the reward for defeating a boss.
+ *
+ * @param state - Boss state at time of defeat
+ * @param boss - Boss configuration data
+ * @returns Reward with spores, lore, and flavor
+ */
+export function calculateBossReward(
+  state: BossState,
+  boss: BossData,
+): BossReward {
+  if (!state.defeated || !state.victoryMethod) {
+    return {
+      spores: 0,
+      loreId: boss.id,
+      loreText: boss.loreEntry,
+      loreTextRu: boss.loreEntryRu,
+      victoryMethod: VictoryMethod.Direct,
+    };
+  }
+
+  // Base reward + bonus for elegant victory methods
+  let spores = boss.sporeReward;
+
+  switch (state.victoryMethod) {
+    case VictoryMethod.Chemical:
+      // Chemical victory: 50% bonus (requires crafting NaOH + timing)
+      spores = Math.round(spores * 1.5);
+      break;
+    case VictoryMethod.Catalytic:
+      // Catalytic victory: 100% bonus (requires observation + Hg)
+      spores = Math.round(spores * 2.0);
+      break;
+    case VictoryMethod.Direct:
+      // Direct victory: base reward
+      break;
+  }
+
+  return {
+    spores,
+    loreId: boss.id,
+    loreText: boss.loreEntry,
+    loreTextRu: boss.loreEntryRu,
+    victoryMethod: state.victoryMethod,
+  };
+}
+
+/**
+ * Apply boss defeat to meta state: add codex entry and spores.
+ *
+ * @param meta - Mutable meta state
+ * @param reward - Boss reward to apply
+ * @param runId - Current run ID
+ */
+export function applyBossReward(
+  meta: MetaState,
+  reward: BossReward,
+  runId: number,
+): void {
+  // Add spores
+  meta.spores += reward.spores;
+
+  // Add boss lore to codex (skip if already exists)
+  const key = `boss:${reward.loreId}`;
+  const exists = meta.codex.some(e => `${e.type}:${e.id}` === key);
+  if (!exists) {
+    const entry: CodexEntry = {
+      id: reward.loreId,
+      type: 'boss' as CodexEntry['type'],
+      discoveredOnRun: runId,
+    };
+    meta.codex.push(entry);
+  }
+}

src/boss/types.ts

@@ -0,0 +1,202 @@
+/**
+ * Boss Fight Types — Archon encounters
+ *
+ * Ouroboros: The Archon of Cycles — a serpent consuming its own tail.
+ * The fight is a cyclical pattern-recognition puzzle with 3 victory paths:
+ * 1. Chemical — NaOH neutralization during acid phase (real acid-base chemistry)
+ * 2. Direct — projectile damage during vulnerability window
+ * 3. Catalytic — Hg catalyst poisoning (real: mercury poisons catalytic sites)
+ */
+
+// ─── Boss Phases ─────────────────────────────────────────────────
+
+/** Cyclical boss attack phases (repeat with escalation) */
+export enum BossPhase {
+  /** Arena constricts — boss coils, safe zone shrinks */
+  Coil = 0,
+  /** Acid projectile spray — rotating pattern */
+  Spray = 1,
+  /** Tail sweep — sector damage arcs */
+  Lash = 2,
+  /** Self-consumption pause — vulnerability window */
+  Digest = 3,
+}
+
+export const BOSS_PHASE_COUNT = 4;
+
+export const BOSS_PHASE_NAMES: Record<BossPhase, string> = {
+  [BossPhase.Coil]: 'Coil',
+  [BossPhase.Spray]: 'Acid Spray',
+  [BossPhase.Lash]: 'Tail Lash',
+  [BossPhase.Digest]: 'Digest',
+};
+
+export const BOSS_PHASE_NAMES_RU: Record<BossPhase, string> = {
+  [BossPhase.Coil]: 'Сжатие',
+  [BossPhase.Spray]: 'Кислотный Залп',
+  [BossPhase.Lash]: 'Удар Хвостом',
+  [BossPhase.Digest]: 'Переваривание',
+};
+
+// ─── Victory Methods ─────────────────────────────────────────────
+
+/** How the boss was defeated (determines reward flavor) */
+export enum VictoryMethod {
+  /** NaOH acid-base neutralization during Spray phase */
+  Chemical = 'chemical',
+  /** Brute force projectile damage during Digest */
+  Direct = 'direct',
+  /** Hg catalyst poisoning — disrupts self-catalysis */
+  Catalytic = 'catalytic',
+}
+
+// ─── Boss Data (from JSON) ──────────────────────────────────────
+
+/** Boss configuration loaded from bosses.json */
+export interface BossData {
+  id: string;
+  name: string;
+  nameRu: string;
+  description: string;
+  descriptionRu: string;
+
+  /** Hex color string for rendering */
+  color: string;
+  /** Base radius in pixels */
+  radius: number;
+
+  /** Maximum health points */
+  health: number;
+  /** Damage reduction 0–1 during non-vulnerable phases */
+  armor: number;
+  /** Damage reduction 0–1 during vulnerable phases */
+  armorVulnerable: number;
+  /** HP regeneration per second (self-catalysis) */
+  regenPerSecond: number;
+  /** Base attack damage to player */
+  damage: number;
+
+  /** Phase durations in ms: [Coil, Spray, Lash, Digest] */
+  phaseDurations: [number, number, number, number];
+  /** Duration multiplier per completed cycle (< 1 = faster) */
+  phaseSpeedupPerCycle: number;
+  /** Difficulty caps after this many cycles */
+  maxCycles: number;
+
+  /** BossPhase values where boss takes full damage */
+  vulnerablePhases: number[];
+  /** Compound ID that deals bonus chemical damage */
+  chemicalWeakness: string;
+  /** Damage multiplier for chemical weakness */
+  chemicalDamageMultiplier: number;
+  /** Phases where chemical weakness applies (e.g. Spray for NaOH) */
+  chemicalEffectivePhases: number[];
+  /** Element symbol that acts as catalyst poison */
+  catalystPoison: string;
+  /** Regen reduction per catalyst stack (HP/s) */
+  catalystRegenReduction: number;
+  /** Armor reduction per catalyst stack (absolute) */
+  catalystArmorReduction: number;
+  /** Maximum catalyst stacks */
+  maxCatalystStacks: number;
+
+  /** Arena radius in tiles */
+  arenaRadius: number;
+
+  /** Lore text revealed on victory (English) */
+  loreEntry: string;
+  /** Lore text revealed on victory (Russian) */
+  loreEntryRu: string;
+
+  /** Spore reward for defeating the boss */
+  sporeReward: number;
+}
+
+// ─── Runtime Boss State ──────────────────────────────────────────
+
+/** Runtime state of the boss fight (stored in scene, not ECS) */
+export interface BossState {
+  /** Boss data ID */
+  bossId: string;
+  /** Current health */
+  health: number;
+  /** Maximum health */
+  maxHealth: number;
+  /** Current attack phase */
+  currentPhase: BossPhase;
+  /** Time remaining in current phase (ms) */
+  phaseTimer: number;
+  /** Number of completed full cycles (Coil→Spray→Lash→Digest) */
+  cycleCount: number;
+  /** Number of catalyst poison (Hg) applications */
+  catalystStacks: number;
+  /** Whether the boss has been defeated */
+  defeated: boolean;
+  /** How the boss was defeated (null if not yet) */
+  victoryMethod: VictoryMethod | null;
+  /** Running totals by damage type */
+  totalDamageDealt: number;
+  chemicalDamageDealt: number;
+  directDamageDealt: number;
+  catalystDamageDealt: number;
+}
+
+// ─── Damage Result ──────────────────────────────────────────────
+
+/** Result of applying damage to the boss */
+export interface BossDamageResult {
+  /** Actual damage dealt after armor */
+  damageDealt: number;
+  /** Type of damage */
+  damageType: VictoryMethod;
+  /** Whether this was a killing blow */
+  killingBlow: boolean;
+  /** Whether a catalyst stack was applied */
+  catalystApplied: boolean;
+  /** Feedback message for player */
+  message: string;
+  messageRu: string;
+}
+
+// ─── Boss Phase Event ───────────────────────────────────────────
+
+/** Events emitted during boss phase updates */
+export interface BossPhaseEvent {
+  type: 'phase_change' | 'cycle_complete' | 'boss_attack';
+  phase: BossPhase;
+  cycleCount: number;
+}
+
+// ─── Arena Data ─────────────────────────────────────────────────
+
+/** Generated arena tile layout */
+export interface ArenaData {
+  /** Tile grid (same format as WorldData.grid) */
+  grid: number[][];
+  /** Arena width in tiles */
+  width: number;
+  /** Arena height in tiles */
+  height: number;
+  /** Boss spawn position in pixels */
+  bossSpawnX: number;
+  bossSpawnY: number;
+  /** Player spawn position in pixels */
+  playerSpawnX: number;
+  playerSpawnY: number;
+  /** Resource deposit positions in pixels */
+  resourcePositions: { x: number; y: number }[];
+}
+
+// ─── Boss Reward ────────────────────────────────────────────────
+
+/** Reward for defeating the boss */
+export interface BossReward {
+  /** Spores earned */
+  spores: number;
+  /** Lore text for Codex */
+  loreId: string;
+  loreText: string;
+  loreTextRu: string;
+  /** Victory method determines flavor */
+  victoryMethod: VictoryMethod;
+}

src/boss/victory.ts

@@ -0,0 +1,178 @@
+/**
+ * Boss Victory Conditions — 3 paths to defeating an Archon
+ *
+ * 1. Chemical: NaOH during Spray phase (acid-base neutralization)
+ * 2. Direct: Any projectile during Digest vulnerability window
+ * 3. Catalytic: Hg poison stacks (disrupts self-catalysis)
+ *
+ * Real science behind each method:
+ * - NaOH + HCl → NaCl + H₂O (neutralization of Ouroboros acid)
+ * - Mercury poisons catalytic sites (real catalysis chemistry)
+ * - Direct damage exploits the brief self-consumption pause
+ */
+
+import { VictoryMethod, type BossData, type BossState, type BossDamageResult } from './types';
+import { getEffectiveArmor, isVulnerable } from './ai';
+
+/** Base damage from a projectile hit */
+const PROJECTILE_BASE_DAMAGE = 15;
+
+/** Damage dealt by catalyst poison application */
+const CATALYST_DAMAGE = 10;
+
+/**
+ * Apply damage to the boss from a projectile hit.
+ * Determines damage type based on the item used and current boss phase.
+ *
+ * @param state - Mutable boss state
+ * @param boss - Immutable boss data
+ * @param itemId - The element/compound symbol used (e.g. "NaOH", "Hg", "Fe")
+ * @returns Damage result with feedback
+ */
+export function applyBossDamage(
+  state: BossState,
+  boss: BossData,
+  itemId: string,
+): BossDamageResult {
+  if (state.defeated) {
+    return {
+      damageDealt: 0,
+      damageType: VictoryMethod.Direct,
+      killingBlow: false,
+      catalystApplied: false,
+      message: 'Boss already defeated',
+      messageRu: 'Босс уже побеждён',
+    };
+  }
+
+  const armor = getEffectiveArmor(state, boss);
+
+  // Path 3: Catalyst poison (Hg)
+  if (itemId === boss.catalystPoison) {
+    return applyCatalystDamage(state, boss, armor);
+  }
+
+  // Path 1: Chemical weakness (NaOH during Spray)
+  if (
+    itemId === boss.chemicalWeakness &&
+    boss.chemicalEffectivePhases.includes(state.currentPhase)
+  ) {
+    return applyChemicalDamage(state, boss, armor);
+  }
+
+  // Path 2: Direct damage (any projectile during vulnerable phase)
+  if (isVulnerable(state, boss)) {
+    return applyDirectDamage(state, boss, armor);
+  }
+
+  // Non-vulnerable phase, non-special item → heavily reduced damage
+  const reducedDamage = Math.max(1, Math.round(PROJECTILE_BASE_DAMAGE * (1 - armor)));
+  return dealDamage(state, reducedDamage, VictoryMethod.Direct, false, {
+    message: `Ouroboros absorbs the blow (${reducedDamage} dmg)`,
+    messageRu: `Уроборос поглощает удар (${reducedDamage} урона)`,
+  });
+}
+
+/** Apply chemical damage (NaOH neutralization) */
+function applyChemicalDamage(
+  state: BossState,
+  boss: BossData,
+  armor: number,
+): BossDamageResult {
+  const rawDamage = PROJECTILE_BASE_DAMAGE * boss.chemicalDamageMultiplier;
+  const damage = Math.max(1, Math.round(rawDamage * (1 - armor)));
+
+  return dealDamage(state, damage, VictoryMethod.Chemical, false, {
+    message: `Acid neutralized! NaOH + acid → salt + water (${damage} dmg)`,
+    messageRu: `Кислота нейтрализована! NaOH + кислота → соль + вода (${damage} урона)`,
+  });
+}
+
+/** Apply direct projectile damage during vulnerability */
+function applyDirectDamage(
+  state: BossState,
+  boss: BossData,
+  armor: number,
+): BossDamageResult {
+  const damage = Math.max(1, Math.round(PROJECTILE_BASE_DAMAGE * (1 - armor)));
+
+  return dealDamage(state, damage, VictoryMethod.Direct, false, {
+    message: `Hit during digestion! (${damage} dmg)`,
+    messageRu: `Попадание во время переваривания! (${damage} урона)`,
+  });
+}
+
+/** Apply catalyst poison (Hg) */
+function applyCatalystDamage(
+  state: BossState,
+  boss: BossData,
+  armor: number,
+): BossDamageResult {
+  let catalystApplied = false;
+  let message: string;
+  let messageRu: string;
+
+  if (state.catalystStacks < boss.maxCatalystStacks) {
+    state.catalystStacks += 1;
+    catalystApplied = true;
+    message = `Mercury poisons catalytic site! Stack ${state.catalystStacks}/${boss.maxCatalystStacks} — regen and armor permanently reduced`;
+    messageRu = `Ртуть отравляет каталитический центр! Стак ${state.catalystStacks}/${boss.maxCatalystStacks} — регенерация и броня снижены навсегда`;
+  } else {
+    message = `Catalyst fully poisoned (${CATALYST_DAMAGE} dmg)`;
+    messageRu = `Катализатор полностью отравлен (${CATALYST_DAMAGE} урона)`;
+  }
+
+  const damage = Math.max(1, Math.round(CATALYST_DAMAGE * (1 - armor)));
+
+  return dealDamage(state, damage, VictoryMethod.Catalytic, catalystApplied, {
+    message,
+    messageRu,
+  });
+}
+
+/** Common damage application logic */
+function dealDamage(
+  state: BossState,
+  damage: number,
+  damageType: VictoryMethod,
+  catalystApplied: boolean,
+  messages: { message: string; messageRu: string },
+): BossDamageResult {
+  state.health = Math.max(0, state.health - damage);
+  state.totalDamageDealt += damage;
+
+  // Track damage by type
+  switch (damageType) {
+    case VictoryMethod.Chemical:
+      state.chemicalDamageDealt += damage;
+      break;
+    case VictoryMethod.Direct:
+      state.directDamageDealt += damage;
+      break;
+    case VictoryMethod.Catalytic:
+      state.catalystDamageDealt += damage;
+      break;
+  }
+
+  // Check for killing blow
+  const killingBlow = state.health <= 0;
+  if (killingBlow) {
+    state.defeated = true;
+    state.victoryMethod = damageType;
+  }
+
+  return {
+    damageDealt: damage,
+    damageType,
+    killingBlow,
+    catalystApplied,
+    ...messages,
+  };
+}
+
+/**
+ * Check if the boss is defeated.
+ */
+export function isBossDefeated(state: BossState): boolean {
+  return state.defeated;
+}

src/chemistry/types.ts

@@ -8,7 +8,8 @@ export type ElementCategory =
   | 'metalloid'
   | 'nonmetal'
   | 'halogen'
-  | 'noble-gas';
+  | 'noble-gas'
+  | 'actinide';
 
 export type MatterState = 'solid' | 'liquid' | 'gas';
 

src/config.ts

@@ -1,6 +1,12 @@
 import Phaser from 'phaser';
 import { BootScene } from './scenes/BootScene';
+import { CradleScene } from './scenes/CradleScene';
 import { GameScene } from './scenes/GameScene';
+import { UIScene } from './scenes/UIScene';
+import { DeathScene } from './scenes/DeathScene';
+import { FractalScene } from './scenes/FractalScene';
+import { BossArenaScene } from './scenes/BossArenaScene';
+import { RenewalScene } from './scenes/RenewalScene';
 
 export const GAME_WIDTH = 1280;
 export const GAME_HEIGHT = 720;
@@ -11,7 +17,7 @@ export const gameConfig: Phaser.Types.Core.GameConfig = {
   height: GAME_HEIGHT,
   backgroundColor: '#0a0a0a',
   parent: document.body,
-  scene: [BootScene, GameScene],
+  scene: [BootScene, CradleScene, GameScene, UIScene, DeathScene, FractalScene, RenewalScene, BossArenaScene],
   physics: {
     default: 'arcade',
     arcade: {

src/creatures/ai.ts

@@ -0,0 +1,350 @@
+/**
+ * Creature AI System — Finite State Machine
+ *
+ * States: Idle → Wander → Feed → Flee → Attack
+ * Transitions based on hunger, threats, territory.
+ *
+ * Pure function system — reads/writes ECS components only.
+ */
+
+import { query } from 'bitecs';
+import type { World } from '../ecs/world';
+import {
+  Position,
+  Velocity,
+  Health,
+  Creature,
+  AI,
+  Metabolism,
+  LifeCycle,
+  PlayerTag,
+  Resource,
+} from '../ecs/components';
+import { AIState, LifeStage, SpeciesId } from './types';
+import type { SpeciesData } from './types';
+
+/** Seeded pseudo-random for AI decisions (deterministic per frame) */
+function aiRandom(eid: number, tick: number): number {
+  let h = ((eid * 2654435761) ^ (tick * 2246822507)) >>> 0;
+  h = Math.imul(h ^ (h >>> 16), 0x45d9f3b);
+  h = Math.imul(h ^ (h >>> 16), 0x45d9f3b);
+  return ((h ^ (h >>> 16)) >>> 0) / 4294967296;
+}
+
+/** Calculate squared distance between two entities */
+function distSq(ax: number, ay: number, bx: number, by: number): number {
+  const dx = ax - bx;
+  const dy = ay - by;
+  return dx * dx + dy * dy;
+}
+
+/** Set velocity toward a target position at given speed */
+function moveToward(
+  eid: number,
+  targetX: number,
+  targetY: number,
+  speed: number,
+): void {
+  const dx = targetX - Position.x[eid];
+  const dy = targetY - Position.y[eid];
+  const dist = Math.sqrt(dx * dx + dy * dy);
+  if (dist < 1) {
+    Velocity.vx[eid] = 0;
+    Velocity.vy[eid] = 0;
+    return;
+  }
+  Velocity.vx[eid] = (dx / dist) * speed;
+  Velocity.vy[eid] = (dy / dist) * speed;
+}
+
+/** Set velocity away from a position at given speed */
+function moveAway(
+  eid: number,
+  fromX: number,
+  fromY: number,
+  speed: number,
+): void {
+  const dx = Position.x[eid] - fromX;
+  const dy = Position.y[eid] - fromY;
+  const dist = Math.sqrt(dx * dx + dy * dy);
+  if (dist < 1) {
+    // Random direction when exactly on top
+    Velocity.vx[eid] = speed;
+    Velocity.vy[eid] = 0;
+    return;
+  }
+  Velocity.vx[eid] = (dx / dist) * speed;
+  Velocity.vy[eid] = (dy / dist) * speed;
+}
+
+/**
+ * Find the nearest entity matching a predicate.
+ * @returns [eid, distanceSquared] or [-1, Infinity] if none found
+ */
+function findNearest(
+  world: World,
+  fromX: number,
+  fromY: number,
+  candidates: number[],
+  maxDistSq: number,
+): [number, number] {
+  let bestEid = -1;
+  let bestDist = Infinity;
+
+  for (const eid of candidates) {
+    const d = distSq(fromX, fromY, Position.x[eid], Position.y[eid]);
+    if (d < bestDist && d <= maxDistSq) {
+      bestDist = d;
+      bestEid = eid;
+    }
+  }
+
+  return [bestEid, bestDist];
+}
+
+/**
+ * AI System — runs FSM transitions and actions for all creatures.
+ *
+ * @param speciesLookup - map from SpeciesId to species stats
+ * @param tick - current game tick (for deterministic randomness)
+ * @param aggroMultiplier - multiplier on flee/aggression radius (default 1.0, e.g. Naturalist bonus)
+ */
+export function aiSystem(
+  world: World,
+  deltaMs: number,
+  speciesLookup: Map<number, SpeciesData>,
+  tick: number,
+  aggroMultiplier = 1.0,
+): void {
+  const dt = deltaMs / 1000;
+  const creatures = query(world, [Creature, AI, Position, Velocity, Metabolism, LifeCycle]);
+
+  // Gather player positions for flee calculations
+  const players = query(world, [PlayerTag, Position]);
+  const playerPositions = players.map(eid => ({
+    x: Position.x[eid],
+    y: Position.y[eid],
+    eid,
+  }));
+
+  // Gather resource positions for feeding
+  const resources = query(world, [Resource, Position]);
+
+  for (const eid of creatures) {
+    // Eggs don't act
+    if (LifeCycle.stage[eid] === LifeStage.Egg) {
+      Velocity.vx[eid] = 0;
+      Velocity.vy[eid] = 0;
+      continue;
+    }
+
+    const species = speciesLookup.get(Creature.speciesId[eid]);
+    if (!species) continue;
+
+    const speed = LifeCycle.stage[eid] === LifeStage.Youth
+      ? species.speed * 0.7
+      : LifeCycle.stage[eid] === LifeStage.Aging
+      ? species.speed * 0.5
+      : species.speed;
+
+    // Reduce attack cooldown
+    if (AI.attackCooldown[eid] > 0) {
+      AI.attackCooldown[eid] -= deltaMs;
+    }
+
+    // Reduce state timer
+    AI.stateTimer[eid] -= deltaMs;
+
+    // ─── Check for threats (player proximity) ───
+    let nearestThreatDist = Infinity;
+    let nearestThreatX = 0;
+    let nearestThreatY = 0;
+
+    for (const p of playerPositions) {
+      const d = distSq(Position.x[eid], Position.y[eid], p.x, p.y);
+      if (d < nearestThreatDist) {
+        nearestThreatDist = d;
+        nearestThreatX = p.x;
+        nearestThreatY = p.y;
+      }
+    }
+
+    const effectiveFleeRadius = species.fleeRadius * aggroMultiplier;
+    const fleeRadiusSq = effectiveFleeRadius * effectiveFleeRadius;
+    const shouldFlee = nearestThreatDist < fleeRadiusSq
+      && species.speciesId !== SpeciesId.Reagent; // Reagents don't flee
+
+    // ─── Check hunger ───
+    const hungerFraction = Metabolism.energy[eid] / Metabolism.energyMax[eid];
+    const isHungry = hungerFraction < Metabolism.hungerThreshold[eid];
+
+    // ─── Check for prey (Reagents only) ───
+    const effectiveAggrRadius = species.aggressionRadius * aggroMultiplier;
+    const aggrRadiusSq = effectiveAggrRadius * effectiveAggrRadius;
+    let nearestPreyEid = -1;
+    let nearestPreyDist = Infinity;
+
+    if (species.speciesId === SpeciesId.Reagent) {
+      // Reagents hunt other creatures (non-Reagent)
+      for (const other of creatures) {
+        if (other === eid) continue;
+        if (Creature.speciesId[other] === SpeciesId.Reagent) continue;
+        if (LifeCycle.stage[other] === LifeStage.Egg) continue;
+
+        const d = distSq(Position.x[eid], Position.y[eid], Position.x[other], Position.y[other]);
+        if (d < nearestPreyDist && d <= aggrRadiusSq) {
+          nearestPreyDist = d;
+          nearestPreyEid = other;
+        }
+      }
+    }
+
+    // ─── State transitions ───
+    const currentState = AI.state[eid];
+
+    if (shouldFlee && currentState !== AIState.Flee) {
+      // Threat detected → flee
+      AI.state[eid] = AIState.Flee;
+      AI.stateTimer[eid] = 2000;
+    } else if (nearestPreyEid >= 0 && isHungry && currentState !== AIState.Attack) {
+      // Prey spotted and hungry → attack
+      AI.state[eid] = AIState.Attack;
+      AI.targetEid[eid] = nearestPreyEid;
+      AI.stateTimer[eid] = 5000;
+    } else if (isHungry && currentState !== AIState.Feed && currentState !== AIState.Flee && currentState !== AIState.Attack) {
+      // Hungry → feed (but don't interrupt active attack)
+      AI.state[eid] = AIState.Feed;
+      AI.stateTimer[eid] = 8000;
+    } else if (AI.stateTimer[eid] <= 0) {
+      // Timer expired → cycle between idle and wander
+      if (currentState === AIState.Idle) {
+        AI.state[eid] = AIState.Wander;
+        AI.stateTimer[eid] = 3000 + aiRandom(eid, tick) * 4000;
+      } else if (currentState === AIState.Wander) {
+        AI.state[eid] = AIState.Idle;
+        AI.stateTimer[eid] = 1000 + aiRandom(eid, tick) * 2000;
+      } else if (currentState === AIState.Feed) {
+        // Couldn't find food → wander
+        AI.state[eid] = AIState.Wander;
+        AI.stateTimer[eid] = 3000;
+      } else if (currentState === AIState.Flee) {
+        AI.state[eid] = AIState.Wander;
+        AI.stateTimer[eid] = 2000;
+      } else if (currentState === AIState.Attack) {
+        AI.state[eid] = AIState.Wander;
+        AI.stateTimer[eid] = 2000;
+      }
+    }
+
+    // ─── Execute current state behavior ───
+    switch (AI.state[eid]) {
+      case AIState.Idle: {
+        Velocity.vx[eid] = 0;
+        Velocity.vy[eid] = 0;
+        break;
+      }
+
+      case AIState.Wander: {
+        // Random direction, clamped to wander radius from home
+        const homeDist = Math.sqrt(distSq(
+          Position.x[eid], Position.y[eid],
+          AI.homeX[eid], AI.homeY[eid],
+        ));
+
+        if (homeDist > species.wanderRadius) {
+          // Too far from home → head back
+          moveToward(eid, AI.homeX[eid], AI.homeY[eid], speed * 0.6);
+        } else {
+          // Pick new random direction periodically
+          const phase = Math.floor(AI.stateTimer[eid] / 1000);
+          const angle = aiRandom(eid, tick + phase) * Math.PI * 2;
+          Velocity.vx[eid] = Math.cos(angle) * speed * 0.5;
+          Velocity.vy[eid] = Math.sin(angle) * speed * 0.5;
+        }
+        break;
+      }
+
+      case AIState.Feed: {
+        if (species.diet === 'mineral') {
+          // Find nearest resource entity
+          const [nearResEid, nearResDist] = findNearest(
+            world,
+            Position.x[eid], Position.y[eid],
+            [...resources],
+            (species.wanderRadius * 2) ** 2,
+          );
+
+          if (nearResEid >= 0) {
+            const feedRangeSq = 30 * 30;
+            if (nearResDist < feedRangeSq) {
+              // Close enough — feed (handled by metabolism system)
+              Velocity.vx[eid] = 0;
+              Velocity.vy[eid] = 0;
+            } else {
+              moveToward(eid, Position.x[nearResEid], Position.y[nearResEid], speed);
+            }
+          } else {
+            // No resources found → wander to look for food
+            const angle = aiRandom(eid, tick) * Math.PI * 2;
+            Velocity.vx[eid] = Math.cos(angle) * speed * 0.5;
+            Velocity.vy[eid] = Math.sin(angle) * speed * 0.5;
+          }
+        } else if (species.diet === 'creature') {
+          // Predator — same as attack but passive searching
+          const angle = aiRandom(eid, tick) * Math.PI * 2;
+          Velocity.vx[eid] = Math.cos(angle) * speed * 0.7;
+          Velocity.vy[eid] = Math.sin(angle) * speed * 0.7;
+        }
+        break;
+      }
+
+      case AIState.Flee: {
+        moveAway(eid, nearestThreatX, nearestThreatY, speed * 1.3);
+        break;
+      }
+
+      case AIState.Attack: {
+        const target = AI.targetEid[eid];
+        if (target < 0) {
+          AI.state[eid] = AIState.Wander;
+          AI.stateTimer[eid] = 2000;
+          break;
+        }
+
+        const targetDist = distSq(
+          Position.x[eid], Position.y[eid],
+          Position.x[target], Position.y[target],
+        );
+        const attackRangeSq = species.attackRange * species.attackRange;
+
+        if (targetDist <= attackRangeSq) {
+          // In range — deal damage if cooldown ready
+          Velocity.vx[eid] = 0;
+          Velocity.vy[eid] = 0;
+          if (AI.attackCooldown[eid] <= 0) {
+            const dmg = LifeCycle.stage[eid] === LifeStage.Youth
+              ? species.damage * 0.5
+              : species.damage;
+            Health.current[target] -= dmg;
+            AI.attackCooldown[eid] = species.attackCooldown;
+
+            // Gain energy from kill if target dies
+            if (Health.current[target] <= 0) {
+              Metabolism.energy[eid] = Math.min(
+                Metabolism.energy[eid] + Metabolism.feedAmount[eid],
+                Metabolism.energyMax[eid],
+              );
+              AI.state[eid] = AIState.Wander;
+              AI.stateTimer[eid] = 3000;
+              AI.targetEid[eid] = -1;
+            }
+          }
+        } else {
+          // Chase target
+          moveToward(eid, Position.x[target], Position.y[target], speed);
+        }
+        break;
+      }
+    }
+  }
+}

src/creatures/factory.ts

@@ -0,0 +1,115 @@
+/**
+ * Creature Factory — creates creature entities in the ECS world
+ *
+ * Each creature gets: Position, Velocity, Health, SpriteRef,
+ * Creature, AI, Metabolism, LifeCycle components.
+ */
+
+import { addEntity, addComponent } from 'bitecs';
+import type { World } from '../ecs/world';
+import {
+  Position,
+  Velocity,
+  Health,
+  SpriteRef,
+  Creature,
+  AI,
+  Metabolism,
+  LifeCycle,
+} from '../ecs/components';
+import { AIState, LifeStage } from './types';
+import type { SpeciesData, CreatureInfo } from './types';
+
+/**
+ * Create a creature entity from species data at a given position.
+ * Starts at the Egg stage (immobile).
+ *
+ * @returns entity ID
+ */
+export function createCreatureEntity(
+  world: World,
+  species: SpeciesData,
+  x: number,
+  y: number,
+  startStage: LifeStage = LifeStage.Egg,
+): number {
+  const eid = addEntity(world);
+
+  // Position
+  addComponent(world, eid, Position);
+  Position.x[eid] = x;
+  Position.y[eid] = y;
+
+  // Velocity (starts at 0 — eggs don't move)
+  addComponent(world, eid, Velocity);
+  Velocity.vx[eid] = 0;
+  Velocity.vy[eid] = 0;
+
+  // Health — scaled by life stage
+  addComponent(world, eid, Health);
+  const healthScale = startStage === LifeStage.Egg ? 0.3
+    : startStage === LifeStage.Youth ? 0.6
+    : startStage === LifeStage.Aging ? 0.7
+    : 1.0;
+  const hp = Math.round(species.health * healthScale);
+  Health.current[eid] = hp;
+  Health.max[eid] = hp;
+
+  // Sprite — color from species, radius by stage
+  addComponent(world, eid, SpriteRef);
+  SpriteRef.color[eid] = parseInt(species.color.replace('#', ''), 16);
+  SpriteRef.radius[eid] = startStage <= LifeStage.Youth
+    ? species.radiusYouth
+    : species.radius;
+
+  // Creature tag
+  addComponent(world, eid, Creature);
+  Creature.speciesId[eid] = species.speciesId;
+
+  // AI — starts idle
+  addComponent(world, eid, AI);
+  AI.state[eid] = startStage === LifeStage.Egg ? AIState.Idle : AIState.Wander;
+  AI.stateTimer[eid] = 2000; // 2s initial timer
+  AI.targetEid[eid] = -1;
+  AI.homeX[eid] = x;
+  AI.homeY[eid] = y;
+  AI.attackCooldown[eid] = 0;
+
+  // Metabolism
+  addComponent(world, eid, Metabolism);
+  Metabolism.energy[eid] = species.energyMax * 0.7; // start 70% full
+  Metabolism.energyMax[eid] = species.energyMax;
+  Metabolism.drainRate[eid] = species.energyDrainPerSecond;
+  Metabolism.feedAmount[eid] = species.energyPerFeed;
+  Metabolism.hungerThreshold[eid] = species.hungerThreshold;
+
+  // Life Cycle
+  addComponent(world, eid, LifeCycle);
+  LifeCycle.stage[eid] = startStage;
+  LifeCycle.age[eid] = 0;
+
+  // Set stage timer based on starting stage
+  const stageTimers = [
+    species.eggDuration,
+    species.youthDuration,
+    species.matureDuration,
+    species.agingDuration,
+  ];
+  LifeCycle.stageTimer[eid] = stageTimers[startStage];
+
+  return eid;
+}
+
+/**
+ * Get runtime creature info for string-based lookups.
+ * Used by the creature data map (similar to resourceData pattern).
+ */
+export function getCreatureInfo(
+  eid: number,
+  speciesDataId: string,
+): CreatureInfo {
+  return {
+    speciesId: Creature.speciesId[eid],
+    speciesDataId,
+  };
+}

src/creatures/index.ts

@@ -0,0 +1,21 @@
+/**
+ * Creatures module — re-exports for clean imports
+ */
+
+export { SpeciesId, AIState, LifeStage, SpeciesRegistry } from './types';
+export type { SpeciesData, CreatureInfo, DietType } from './types';
+
+export { createCreatureEntity, getCreatureInfo } from './factory';
+
+export { aiSystem } from './ai';
+export { metabolismSystem, clearMetabolismTracking, resetMetabolismTracking } from './metabolism';
+export { lifeCycleSystem } from './lifecycle';
+export type { LifeCycleEvent } from './lifecycle';
+export { countPopulations, spawnInitialCreatures, reproduce } from './population';
+
+export {
+  creatureProjectileSystem,
+  getObservableCreatures,
+  creatureAttackPlayerSystem,
+} from './interaction';
+export type { CreatureObservation, ProjectileHit } from './interaction';

src/creatures/interaction.ts

@@ -0,0 +1,216 @@
+/**
+ * Creature Interaction — projectile damage, player observation, basic taming
+ *
+ * Handles projectile-creature collision and player proximity detection.
+ */
+
+import { query } from 'bitecs';
+import type { World } from '../ecs/world';
+import {
+  Position,
+  Health,
+  Creature,
+  AI,
+  LifeCycle,
+  Projectile,
+  PlayerTag,
+  Metabolism,
+} from '../ecs/components';
+import { AIState, LifeStage } from './types';
+import type { SpeciesData } from './types';
+import type { ProjectileData } from '../player/projectile';
+import { removeGameEntity } from '../ecs/factory';
+
+/** Projectile hit radius squared (projectile + creature overlap) */
+const HIT_RADIUS_SQ = 20 * 20;
+
+/** Observation range — how close player must be to observe a creature */
+const OBSERVE_RANGE_SQ = 60 * 60;
+
+/** Base projectile damage */
+const PROJECTILE_BASE_DAMAGE = 15;
+
+/** Result of a creature observation */
+export interface CreatureObservation {
+  eid: number;
+  speciesId: number;
+  healthPercent: number;
+  energyPercent: number;
+  stage: LifeStage;
+  aiState: AIState;
+}
+
+/** Result of projectile-creature collision */
+export interface ProjectileHit {
+  creatureEid: number;
+  projectileEid: number;
+  damage: number;
+  killed: boolean;
+  speciesId: number;
+}
+
+/**
+ * Check projectile-creature collisions.
+ * Removes hitting projectiles and deals damage to creatures.
+ *
+ * @param damageMultiplier — optional multiplier on projectile damage (default 1.0, e.g. Mechanic bonus)
+ * @returns Array of hits that occurred
+ */
+export function creatureProjectileSystem(
+  world: World,
+  projData: Map<number, ProjectileData>,
+  speciesLookup: Map<number, SpeciesData>,
+  damageMultiplier = 1.0,
+): ProjectileHit[] {
+  const hits: ProjectileHit[] = [];
+  const projectiles = query(world, [Position, Projectile]);
+  const creatures = query(world, [Creature, Position, Health, LifeCycle]);
+
+  const projectilesToRemove: number[] = [];
+
+  for (const projEid of projectiles) {
+    const px = Position.x[projEid];
+    const py = Position.y[projEid];
+
+    for (const cEid of creatures) {
+      const dx = px - Position.x[cEid];
+      const dy = py - Position.y[cEid];
+      const dSq = dx * dx + dy * dy;
+
+      if (dSq <= HIT_RADIUS_SQ) {
+        // Hit! Calculate damage (with armor reduction and school bonus)
+        const species = speciesLookup.get(Creature.speciesId[cEid]);
+        const armor = species?.armor ?? 0;
+        const damage = Math.round(PROJECTILE_BASE_DAMAGE * (1 - armor) * damageMultiplier);
+
+        Health.current[cEid] -= damage;
+        const killed = Health.current[cEid] <= 0;
+
+        hits.push({
+          creatureEid: cEid,
+          projectileEid: projEid,
+          damage,
+          killed,
+          speciesId: Creature.speciesId[cEid],
+        });
+
+        // Creature becomes aggressive or flees
+        if (!killed && species) {
+          if (species.aggressionRadius > 0) {
+            // Territorial/aggressive → attack the player
+            AI.state[cEid] = AIState.Attack;
+            AI.stateTimer[cEid] = 5000;
+            // Find nearest player to target
+            const players = query(world, [PlayerTag, Position]);
+            if (players.length > 0) {
+              AI.targetEid[cEid] = players[0];
+            }
+          } else {
+            // Passive → flee
+            AI.state[cEid] = AIState.Flee;
+            AI.stateTimer[cEid] = 3000;
+          }
+        }
+
+        projectilesToRemove.push(projEid);
+        break; // one hit per projectile
+      }
+    }
+  }
+
+  // Remove hit projectiles
+  for (const eid of projectilesToRemove) {
+    removeGameEntity(world, eid);
+    projData.delete(eid);
+  }
+
+  return hits;
+}
+
+/**
+ * Get observable creatures near the player.
+ * Returns info about creatures within observation range.
+ */
+export function getObservableCreatures(
+  world: World,
+): CreatureObservation[] {
+  const observations: CreatureObservation[] = [];
+  const players = query(world, [PlayerTag, Position]);
+  if (players.length === 0) return observations;
+
+  const playerX = Position.x[players[0]];
+  const playerY = Position.y[players[0]];
+
+  const creatures = query(world, [Creature, Position, Health, LifeCycle, Metabolism]);
+
+  for (const eid of creatures) {
+    const dx = playerX - Position.x[eid];
+    const dy = playerY - Position.y[eid];
+    const dSq = dx * dx + dy * dy;
+
+    if (dSq <= OBSERVE_RANGE_SQ) {
+      observations.push({
+        eid,
+        speciesId: Creature.speciesId[eid],
+        healthPercent: Health.max[eid] > 0
+          ? Math.round((Health.current[eid] / Health.max[eid]) * 100)
+          : 0,
+        energyPercent: Metabolism.energyMax[eid] > 0
+          ? Math.round((Metabolism.energy[eid] / Metabolism.energyMax[eid]) * 100)
+          : 0,
+        stage: LifeCycle.stage[eid] as LifeStage,
+        aiState: AI.state[eid] as AIState,
+      });
+    }
+  }
+
+  return observations;
+}
+
+/**
+ * Check if player is near any creature for attack damage (creature → player).
+ * Returns total damage dealt to player this frame.
+ */
+export function creatureAttackPlayerSystem(
+  world: World,
+  speciesLookup: Map<number, SpeciesData>,
+): number {
+  let totalDamage = 0;
+
+  const players = query(world, [PlayerTag, Position, Health]);
+  if (players.length === 0) return 0;
+
+  const playerEid = players[0];
+  const playerX = Position.x[playerEid];
+  const playerY = Position.y[playerEid];
+
+  const creatures = query(world, [Creature, AI, Position, LifeCycle]);
+
+  for (const eid of creatures) {
+    if (AI.state[eid] !== AIState.Attack) continue;
+    if (AI.targetEid[eid] !== playerEid) continue;
+    if (LifeCycle.stage[eid] === LifeStage.Egg) continue;
+
+    const species = speciesLookup.get(Creature.speciesId[eid]);
+    if (!species) continue;
+
+    const dx = playerX - Position.x[eid];
+    const dy = playerY - Position.y[eid];
+    const dSq = dx * dx + dy * dy;
+    const rangeSq = species.attackRange * species.attackRange;
+
+    if (dSq <= rangeSq && AI.attackCooldown[eid] <= 0) {
+      const dmg = LifeCycle.stage[eid] === LifeStage.Youth
+        ? species.damage * 0.5
+        : species.damage;
+      totalDamage += dmg;
+      AI.attackCooldown[eid] = species.attackCooldown;
+    }
+  }
+
+  if (totalDamage > 0) {
+    Health.current[playerEid] -= totalDamage;
+  }
+
+  return totalDamage;
+}

src/creatures/lifecycle.ts

@@ -0,0 +1,152 @@
+/**
+ * Life Cycle System — manages creature aging through stages
+ *
+ * Egg → Youth → Mature → Aging → Death
+ *
+ * Each stage has a timer. When it expires, creature advances to next stage.
+ * Stats (health, speed, size) change with each stage.
+ * Death at end of Aging stage returns entity ID for removal + decomposition.
+ */
+
+import { query } from 'bitecs';
+import type { World } from '../ecs/world';
+import {
+  Health,
+  SpriteRef,
+  Creature,
+  AI,
+  Metabolism,
+  LifeCycle,
+} from '../ecs/components';
+import { AIState, LifeStage } from './types';
+import type { SpeciesData } from './types';
+
+/** Result of life cycle processing */
+export interface LifeCycleEvent {
+  type: 'stage_advance' | 'natural_death' | 'ready_to_reproduce';
+  eid: number;
+  speciesId: number;
+  newStage?: LifeStage;
+}
+
+/**
+ * Life cycle system — advances stages, adjusts stats, detects natural death.
+ *
+ * @returns Array of lifecycle events (stage advances, natural deaths, reproduction readiness)
+ */
+export function lifeCycleSystem(
+  world: World,
+  deltaMs: number,
+  speciesLookup: Map<number, SpeciesData>,
+): LifeCycleEvent[] {
+  const events: LifeCycleEvent[] = [];
+
+  for (const eid of query(world, [Creature, LifeCycle])) {
+    const species = speciesLookup.get(Creature.speciesId[eid]);
+    if (!species) continue;
+
+    // Advance age
+    LifeCycle.age[eid] += deltaMs;
+
+    // Decrease stage timer
+    LifeCycle.stageTimer[eid] -= deltaMs;
+
+    // Check for reproduction readiness (mature with enough energy)
+    if (LifeCycle.stage[eid] === LifeStage.Mature) {
+      const energyFraction = Metabolism.energy[eid] / Metabolism.energyMax[eid];
+      if (energyFraction > 0.8) {
+        events.push({
+          type: 'ready_to_reproduce',
+          eid,
+          speciesId: Creature.speciesId[eid],
+        });
+      }
+    }
+
+    // Stage transition when timer expires
+    if (LifeCycle.stageTimer[eid] <= 0) {
+      const currentStage = LifeCycle.stage[eid] as LifeStage;
+
+      switch (currentStage) {
+        case LifeStage.Egg: {
+          // Hatch → Youth
+          LifeCycle.stage[eid] = LifeStage.Youth;
+          LifeCycle.stageTimer[eid] = species.youthDuration;
+
+          // Update visuals — still small
+          SpriteRef.radius[eid] = species.radiusYouth;
+
+          // Enable AI
+          AI.state[eid] = AIState.Wander;
+          AI.stateTimer[eid] = 2000;
+
+          // Scale health up
+          const youthHp = Math.round(species.health * 0.6);
+          Health.current[eid] = youthHp;
+          Health.max[eid] = youthHp;
+
+          events.push({
+            type: 'stage_advance',
+            eid,
+            speciesId: Creature.speciesId[eid],
+            newStage: LifeStage.Youth,
+          });
+          break;
+        }
+
+        case LifeStage.Youth: {
+          // Grow → Mature
+          LifeCycle.stage[eid] = LifeStage.Mature;
+          LifeCycle.stageTimer[eid] = species.matureDuration;
+
+          // Full size and health
+          SpriteRef.radius[eid] = species.radius;
+          Health.current[eid] = species.health;
+          Health.max[eid] = species.health;
+
+          events.push({
+            type: 'stage_advance',
+            eid,
+            speciesId: Creature.speciesId[eid],
+            newStage: LifeStage.Mature,
+          });
+          break;
+        }
+
+        case LifeStage.Mature: {
+          // Age → Aging
+          LifeCycle.stage[eid] = LifeStage.Aging;
+          LifeCycle.stageTimer[eid] = species.agingDuration;
+
+          // Reduced stats
+          const agingHp = Math.round(species.health * 0.7);
+          Health.max[eid] = agingHp;
+          if (Health.current[eid] > agingHp) {
+            Health.current[eid] = agingHp;
+          }
+
+          events.push({
+            type: 'stage_advance',
+            eid,
+            speciesId: Creature.speciesId[eid],
+            newStage: LifeStage.Aging,
+          });
+          break;
+        }
+
+        case LifeStage.Aging: {
+          // Natural death
+          Health.current[eid] = 0;
+          events.push({
+            type: 'natural_death',
+            eid,
+            speciesId: Creature.speciesId[eid],
+          });
+          break;
+        }
+      }
+    }
+  }
+
+  return events;
+}

src/creatures/metabolism.ts

@@ -0,0 +1,124 @@
+/**
+ * Metabolism System — energy drain, feeding, starvation
+ *
+ * Every creature loses energy over time. Feeding near resources restores energy.
+ * Starvation (energy = 0) deals damage over time.
+ */
+
+import { query } from 'bitecs';
+import type { World } from '../ecs/world';
+import {
+  Position,
+  Health,
+  Creature,
+  AI,
+  Metabolism,
+  LifeCycle,
+  Resource,
+} from '../ecs/components';
+import { AIState, LifeStage } from './types';
+import type { ResourceInfo } from '../player/interaction';
+
+/** Damage per second when starving (energy = 0) */
+const STARVATION_DAMAGE_PER_SEC = 5;
+
+/** Feed range squared (pixels) — how close creature must be to resource */
+const FEED_RANGE_SQ = 35 * 35;
+
+/** Minimum time between feeds (ms) */
+const FEED_COOLDOWN_MS = 2000;
+
+/** Tracking last feed time per creature to prevent instant depletion */
+const lastFeedTime = new Map<number, number>();
+
+/**
+ * Metabolism system — drains energy, handles feeding from resources, starvation damage.
+ *
+ * @param resourceData - map of resource entity ID → info (for depletion tracking)
+ * @param elapsed - total elapsed time in ms (for feed cooldown)
+ * @returns Array of [creatureEid, elementNumber] pairs for excretion events
+ */
+export function metabolismSystem(
+  world: World,
+  deltaMs: number,
+  resourceData: Map<number, ResourceInfo>,
+  elapsed: number,
+): Array<[number, number]> {
+  const dt = deltaMs / 1000;
+  const excretions: Array<[number, number]> = [];
+
+  const creatures = query(world, [Creature, Metabolism, Position, LifeCycle]);
+  const resources = query(world, [Resource, Position]);
+
+  for (const eid of creatures) {
+    // Eggs don't metabolize
+    if (LifeCycle.stage[eid] === LifeStage.Egg) continue;
+
+    // ─── Energy drain ───
+    const drainMultiplier = LifeCycle.stage[eid] === LifeStage.Youth ? 0.7
+      : LifeCycle.stage[eid] === LifeStage.Aging ? 1.3
+      : 1.0;
+
+    Metabolism.energy[eid] -= Metabolism.drainRate[eid] * dt * drainMultiplier;
+
+    // ─── Feeding (if in Feed state and near resource) ───
+    if (AI.state[eid] === AIState.Feed || AI.state[eid] === AIState.Idle) {
+      const lastFed = lastFeedTime.get(eid) ?? 0;
+      if (elapsed - lastFed >= FEED_COOLDOWN_MS) {
+        for (const resEid of resources) {
+          if (Resource.quantity[resEid] <= 0) continue;
+
+          const dx = Position.x[eid] - Position.x[resEid];
+          const dy = Position.y[eid] - Position.y[resEid];
+          const dSq = dx * dx + dy * dy;
+
+          if (dSq <= FEED_RANGE_SQ) {
+            // Feed!
+            Metabolism.energy[eid] = Math.min(
+              Metabolism.energy[eid] + Metabolism.feedAmount[eid],
+              Metabolism.energyMax[eid],
+            );
+            Resource.quantity[resEid] -= 1;
+            lastFeedTime.set(eid, elapsed);
+
+            // Excretion event (species excretes element after feeding)
+            const speciesId = Creature.speciesId[eid];
+            // Excretion element is stored in species data, we pass speciesId
+            // and let the caller resolve what element is excreted
+            excretions.push([eid, speciesId]);
+
+            // Exit Feed state if energy is above threshold
+            const fraction = Metabolism.energy[eid] / Metabolism.energyMax[eid];
+            if (fraction >= Metabolism.hungerThreshold[eid] * 1.5) {
+              AI.state[eid] = AIState.Wander;
+              AI.stateTimer[eid] = 3000;
+            }
+            break; // one feed per tick
+          }
+        }
+      }
+    }
+
+    // ─── Clamp energy ───
+    if (Metabolism.energy[eid] < 0) {
+      Metabolism.energy[eid] = 0;
+    }
+
+    // ─── Starvation damage ───
+    if (Metabolism.energy[eid] <= 0) {
+      Health.current[eid] -= STARVATION_DAMAGE_PER_SEC * dt;
+    }
+  }
+
+  return excretions;
+}
+
+/** Clear tracking data for a removed creature */
+export function clearMetabolismTracking(eid: number): void {
+  lastFeedTime.delete(eid);
+}
+
+/** Reset all metabolism tracking (for tests) */
+export function resetMetabolismTracking(): void {
+  lastFeedTime.clear();
+}

src/creatures/population.ts

@@ -0,0 +1,170 @@
+/**
+ * Population Dynamics — spawning, reproduction, population caps
+ *
+ * Simplified Lotka-Volterra inspired system:
+ * - Reproduction when mature creatures have high energy
+ * - Population caps per species prevent explosion
+ * - Initial spawning on preferred tiles
+ */
+
+import { query } from 'bitecs';
+import type { World } from '../ecs/world';
+import { Position, Creature, LifeCycle } from '../ecs/components';
+import { LifeStage, SpeciesId } from './types';
+import type { SpeciesData, CreatureInfo } from './types';
+import { createCreatureEntity } from './factory';
+import type { TileGrid, BiomeData } from '../world/types';
+
+/** Simple seeded hash for deterministic spawn placement */
+function spawnHash(x: number, y: number, seed: number, salt: number): number {
+  return (((x * 48611) ^ (y * 29423) ^ (seed * 61379) ^ (salt * 73757)) >>> 0) / 4294967296;
+}
+
+/** Count living creatures per species */
+export function countPopulations(world: World): Map<number, number> {
+  const counts = new Map<number, number>();
+  for (const eid of query(world, [Creature])) {
+    const sid = Creature.speciesId[eid];
+    counts.set(sid, (counts.get(sid) ?? 0) + 1);
+  }
+  return counts;
+}
+
+/**
+ * Spawn initial creatures across the map.
+ * Places creatures on preferred tiles using seeded randomness.
+ *
+ * @returns Map of entity ID → CreatureInfo
+ */
+export function spawnInitialCreatures(
+  world: World,
+  grid: TileGrid,
+  biome: BiomeData,
+  seed: number,
+  allSpecies: SpeciesData[],
+): Map<number, CreatureInfo> {
+  const creatureData = new Map<number, CreatureInfo>();
+  const tileSize = biome.tileSize;
+
+  // Build tile name → id map
+  const tileNameToId = new Map<string, number>();
+  for (const tile of biome.tiles) {
+    tileNameToId.set(tile.name, tile.id);
+  }
+
+  for (const species of allSpecies) {
+    // Find preferred tile IDs
+    const preferredIds = new Set<number>();
+    for (const name of species.preferredTiles) {
+      const id = tileNameToId.get(name);
+      if (id !== undefined) preferredIds.add(id);
+    }
+
+    // Collect candidate positions
+    const candidates: Array<{ x: number; y: number }> = [];
+    for (let y = 0; y < grid.length; y++) {
+      for (let x = 0; x < grid[y].length; x++) {
+        if (preferredIds.has(grid[y][x])) {
+          candidates.push({ x, y });
+        }
+      }
+    }
+
+    // Spawn based on weight — deterministic selection
+    const targetCount = Math.min(
+      Math.round(species.maxPopulation * species.spawnWeight),
+      species.maxPopulation,
+    );
+
+    let spawned = 0;
+    for (let i = 0; i < candidates.length && spawned < targetCount; i++) {
+      const { x, y } = candidates[i];
+      const roll = spawnHash(x, y, seed, species.speciesId);
+
+      // Probabilistic placement — spread creatures out
+      if (roll < species.spawnWeight * 0.05) {
+        const px = x * tileSize + tileSize / 2;
+        const py = y * tileSize + tileSize / 2;
+
+        // Start mature for initial population
+        const eid = createCreatureEntity(world, species, px, py, LifeStage.Mature);
+        creatureData.set(eid, {
+          speciesId: species.speciesId,
+          speciesDataId: species.id,
+        });
+        spawned++;
+      }
+    }
+
+    // Fallback: if not enough spawned, place remaining at random candidates
+    if (spawned < targetCount && candidates.length > 0) {
+      for (let i = 0; spawned < targetCount && i < 1000; i++) {
+        const idx = Math.floor(spawnHash(i, spawned, seed, species.speciesId + 100) * candidates.length);
+        const { x, y } = candidates[idx];
+        const px = x * tileSize + tileSize / 2;
+        const py = y * tileSize + tileSize / 2;
+
+        const eid = createCreatureEntity(world, species, px, py, LifeStage.Mature);
+        creatureData.set(eid, {
+          speciesId: species.speciesId,
+          speciesDataId: species.id,
+        });
+        spawned++;
+      }
+    }
+  }
+
+  return creatureData;
+}
+
+/**
+ * Handle reproduction — create offspring near parent.
+ * Called when lifecycle system reports 'ready_to_reproduce' events.
+ *
+ * @param parentEid - entity ID of the reproducing creature
+ * @param species - species data
+ * @param currentPopulation - current count of this species
+ * @returns Array of new creature entity IDs (empty if population cap reached)
+ */
+export function reproduce(
+  world: World,
+  parentEid: number,
+  species: SpeciesData,
+  currentPopulation: number,
+  creatureData: Map<number, CreatureInfo>,
+): number[] {
+  if (currentPopulation >= species.maxPopulation) {
+    return [];
+  }
+
+  const newEids: number[] = [];
+  const maxOffspring = Math.min(
+    species.offspringCount,
+    species.maxPopulation - currentPopulation,
+  );
+
+  const parentX = Position.x[parentEid];
+  const parentY = Position.y[parentEid];
+
+  for (let i = 0; i < maxOffspring; i++) {
+    // Place egg near parent with slight offset
+    const angle = (i / maxOffspring) * Math.PI * 2;
+    const offsetX = Math.cos(angle) * 20;
+    const offsetY = Math.sin(angle) * 20;
+
+    const eid = createCreatureEntity(
+      world, species,
+      parentX + offsetX,
+      parentY + offsetY,
+      LifeStage.Egg,
+    );
+
+    creatureData.set(eid, {
+      speciesId: species.speciesId,
+      speciesDataId: species.id,
+    });
+    newEids.push(eid);
+  }
+
+  return newEids;
+}

src/creatures/types.ts

@@ -0,0 +1,132 @@
+/**
+ * Creature Types — data definitions for the creature/ecology system
+ *
+ * Catalytic Wastes: Crystallids, Acidophiles, Reagents
+ * Kinetic Mountains: Pendulums, Mechanoids, Resonators
+ * Verdant Forests: Symbiotes, Mimics, Spore-bearers
+ */
+
+/** Species identifier (stored as numeric ID in ECS components) */
+export enum SpeciesId {
+  Crystallid = 0,
+  Acidophile = 1,
+  Reagent = 2,
+  Pendulum = 3,
+  Mechanoid = 4,
+  Resonator = 5,
+  Symbiote = 6,
+  Mimic = 7,
+  SporeBearer = 8,
+}
+
+/** AI behavior state (FSM) */
+export enum AIState {
+  Idle = 0,
+  Wander = 1,
+  Feed = 2,
+  Flee = 3,
+  Attack = 4,
+}
+
+/** Life cycle stage */
+export enum LifeStage {
+  Egg = 0,
+  Youth = 1,
+  Mature = 2,
+  Aging = 3,
+}
+
+/** Diet type — what a creature can feed on */
+export type DietType = 'mineral' | 'acid' | 'creature';
+
+/** Species definition loaded from creatures.json */
+export interface SpeciesData {
+  id: string;
+  name: string;
+  nameRu: string;
+  speciesId: SpeciesId;
+  biome: string;             // biome id this species belongs to
+  description: string;
+  descriptionRu: string;
+
+  /** Visual */
+  color: string;       // hex color string
+  radius: number;      // base radius in pixels
+  radiusYouth: number; // smaller when young
+
+  /** Stats */
+  health: number;
+  speed: number;       // pixels per second
+  damage: number;      // damage per attack
+  armor: number;       // damage reduction (0-1)
+
+  /** Metabolism */
+  diet: DietType;
+  dietTiles: string[];         // tile names this species feeds on
+  excretionElement: number;    // atomic number of excreted element (0 = none)
+  energyMax: number;           // max energy capacity
+  energyPerFeed: number;       // energy gained per feeding
+  energyDrainPerSecond: number; // passive energy loss rate
+  hungerThreshold: number;     // below this → seek food (0-1 fraction of max)
+
+  /** Behavior */
+  aggressionRadius: number;  // distance to detect threats
+  fleeRadius: number;        // distance to start fleeing
+  wanderRadius: number;      // max wander distance from home
+  attackRange: number;       // melee attack range
+  attackCooldown: number;    // ms between attacks
+
+  /** Life cycle durations (ms) */
+  eggDuration: number;
+  youthDuration: number;
+  matureDuration: number;
+  agingDuration: number;
+
+  /** Reproduction */
+  reproductionEnergy: number;  // energy cost to reproduce
+  offspringCount: number;      // eggs per reproduction event
+
+  /** Population */
+  maxPopulation: number;        // per-species cap
+  spawnWeight: number;          // relative spawn density (0-1)
+  preferredTiles: string[];     // tiles where this species spawns
+}
+
+/** Runtime creature state (non-ECS, for string data lookup) */
+export interface CreatureInfo {
+  speciesId: SpeciesId;
+  speciesDataId: string;   // key into species registry
+}
+
+/** Creature species registry */
+export class SpeciesRegistry {
+  private byId = new Map<string, SpeciesData>();
+  private byNumericId = new Map<SpeciesId, SpeciesData>();
+
+  constructor(data: SpeciesData[]) {
+    for (const species of data) {
+      this.byId.set(species.id, species);
+      this.byNumericId.set(species.speciesId, species);
+    }
+  }
+
+  /** Get species by string ID */
+  get(id: string): SpeciesData | undefined {
+    return this.byId.get(id);
+  }
+
+  /** Get species by numeric ID (from ECS component) */
+  getByNumericId(id: SpeciesId): SpeciesData | undefined {
+    return this.byNumericId.get(id);
+  }
+
+  /** Get all species */
+  getAll(): SpeciesData[] {
+    return [...this.byId.values()];
+  }
+
+  /** Get species count */
+  get count(): number {
+    return this.byId.size;
+  }
+}

src/data/biomes.json

@@ -34,5 +34,77 @@
       "geyserOnTile": 4,
       "mineralOnTiles": [0, 1, 2]
     }
+  },
+  {
+    "id": "kinetic-mountains",
+    "name": "Kinetic Mountains",
+    "nameRu": "Кинетические Горы",
+    "description": "Towering cliffs embedded with ancient gears and pendulums. Anomalous gravity zones, avalanche-prone slopes, and whirring mechanical ruins.",
+    "descriptionRu": "Высокие скалы с вросшими древними шестернями и маятниками. Зоны аномальной гравитации, лавиноопасные склоны и гудящие механические руины.",
+    "tileSize": 32,
+    "mapWidth": 80,
+    "mapHeight": 80,
+    "tiles": [
+      { "id": 0, "name": "bare-rock",      "nameRu": "Голый камень",           "color": "#5a5a5a", "walkable": true,  "damage": 0,  "interactive": false, "resource": false },
+      { "id": 1, "name": "gravel-slope",   "nameRu": "Гравийный склон",        "color": "#7a7a6e", "walkable": true,  "damage": 0,  "interactive": false, "resource": false },
+      { "id": 2, "name": "iron-ridge",     "nameRu": "Железный хребет",        "color": "#4a3a2a", "walkable": true,  "damage": 0,  "interactive": false, "resource": false },
+      { "id": 3, "name": "chasm",          "nameRu": "Пропасть",              "color": "#0a0a1a", "walkable": false, "damage": 15, "interactive": false, "resource": false },
+      { "id": 4, "name": "gear-floor",     "nameRu": "Шестерёночный пол",      "color": "#8b7355", "walkable": true,  "damage": 0,  "interactive": false, "resource": false },
+      { "id": 5, "name": "magnetic-field", "nameRu": "Магнитное поле",         "color": "#3344aa", "walkable": true,  "damage": 2,  "interactive": false, "resource": false },
+      { "id": 6, "name": "steam-vent",     "nameRu": "Паровой клапан",         "color": "#cccccc", "walkable": false, "damage": 0,  "interactive": true,  "resource": false },
+      { "id": 7, "name": "ore-deposit",    "nameRu": "Рудное месторождение",   "color": "#b87333", "walkable": true,  "damage": 0,  "interactive": false, "resource": true  }
+    ],
+    "generation": {
+      "elevationScale": 0.05,
+      "detailScale": 0.18,
+      "elevationRules": [
+        { "below": 0.15, "tileId": 3 },
+        { "below": 0.25, "tileId": 5 },
+        { "below": 0.50, "tileId": 0 },
+        { "below": 0.68, "tileId": 1 },
+        { "below": 0.82, "tileId": 2 },
+        { "below": 1.00, "tileId": 4 }
+      ],
+      "geyserThreshold": 0.92,
+      "mineralThreshold": 0.88,
+      "geyserOnTile": 5,
+      "mineralOnTiles": [0, 1, 2]
+    }
+  },
+  {
+    "id": "verdant-forests",
+    "name": "Verdant Forests",
+    "nameRu": "Вердантовые Леса",
+    "description": "A multi-layered living forest teeming with biodiversity. Underground mycorrhizal networks, towering canopies, and bioluminescent clearings.",
+    "descriptionRu": "Многоярусный живой лес, кишащий биоразнообразием. Подземные микоризные сети, высочайшие кроны и биолюминесцентные поляны.",
+    "tileSize": 32,
+    "mapWidth": 80,
+    "mapHeight": 80,
+    "tiles": [
+      { "id": 0, "name": "forest-floor",      "nameRu": "Лесная подстилка",      "color": "#1a3a0e", "walkable": true,  "damage": 0, "interactive": false, "resource": false },
+      { "id": 1, "name": "dense-undergrowth", "nameRu": "Густой подлесок",        "color": "#0d2b06", "walkable": true,  "damage": 0, "interactive": false, "resource": false },
+      { "id": 2, "name": "mycelium-carpet",   "nameRu": "Мицелиевый ковёр",       "color": "#4a2a5a", "walkable": true,  "damage": 0, "interactive": false, "resource": false },
+      { "id": 3, "name": "bog",               "nameRu": "Трясина",                "color": "#2a4a1a", "walkable": true,  "damage": 4, "interactive": false, "resource": false },
+      { "id": 4, "name": "toxic-bloom",       "nameRu": "Ядовитый цвет",          "color": "#9a3a6a", "walkable": false, "damage": 8, "interactive": false, "resource": false },
+      { "id": 5, "name": "ancient-tree",      "nameRu": "Древо-Великан",          "color": "#1a2a0a", "walkable": false, "damage": 0, "interactive": false, "resource": false },
+      { "id": 6, "name": "hollow-stump",      "nameRu": "Полый пень",             "color": "#5a4a2a", "walkable": true,  "damage": 0, "interactive": true,  "resource": false },
+      { "id": 7, "name": "herb-patch",        "nameRu": "Лекарственная поляна",   "color": "#2a6a1a", "walkable": true,  "damage": 0, "interactive": false, "resource": true  }
+    ],
+    "generation": {
+      "elevationScale": 0.07,
+      "detailScale": 0.12,
+      "elevationRules": [
+        { "below": 0.18, "tileId": 3 },
+        { "below": 0.28, "tileId": 4 },
+        { "below": 0.55, "tileId": 0 },
+        { "below": 0.72, "tileId": 1 },
+        { "below": 0.86, "tileId": 2 },
+        { "below": 1.00, "tileId": 5 }
+      ],
+      "geyserThreshold": 0.91,
+      "mineralThreshold": 0.87,
+      "geyserOnTile": 2,
+      "mineralOnTiles": [0, 1, 2]
+    }
   }
 ]

src/data/bosses.json

@@ -0,0 +1,31 @@
+[
+  {
+    "id": "ouroboros",
+    "name": "Ouroboros",
+    "nameRu": "Уроборос",
+    "description": "The Archon of Cycles — a serpent consuming its own tail in endless self-catalysis. Its body is both catalyst and substrate.",
+    "descriptionRu": "Архонт Циклов — змей, пожирающий собственный хвост в бесконечном самокатализе. Его тело — и катализатор, и субстрат.",
+    "color": "#cc44ff",
+    "radius": 20,
+    "health": 300,
+    "armor": 0.5,
+    "armorVulnerable": 0.1,
+    "regenPerSecond": 5,
+    "damage": 15,
+    "phaseDurations": [5000, 8000, 6000, 4000],
+    "phaseSpeedupPerCycle": 0.9,
+    "maxCycles": 5,
+    "vulnerablePhases": [3],
+    "chemicalWeakness": "NaOH",
+    "chemicalDamageMultiplier": 3.0,
+    "chemicalEffectivePhases": [1],
+    "catalystPoison": "Hg",
+    "catalystRegenReduction": 2.0,
+    "catalystArmorReduction": 0.1,
+    "maxCatalystStacks": 3,
+    "arenaRadius": 10,
+    "loreEntry": "The first Archon awakens. The Ouroboros — an eternal cycle of self-consumption. Its body is both catalyst and substrate, endlessly breaking itself down and rebuilding. To break its cycle is to understand catalysis itself: that which accelerates change without being consumed... until a poison finds the active site.",
+    "loreEntryRu": "Первый Архонт пробуждается. Уроборос — вечный цикл самопоглощения. Его тело — одновременно катализатор и субстрат, бесконечно разрушающее и восстанавливающее себя. Разорвать его цикл — значит постичь суть катализа: то, что ускоряет изменение, не расходуясь... пока яд не найдёт активный центр.",
+    "sporeReward": 100
+  }
+]

src/data/compounds.json

@@ -198,5 +198,319 @@
     "description": "Explosive mixture of saltpeter, sulfur, and charcoal. The discovery that changed civilizations.",
     "descriptionRu": "Взрывчатая смесь селитры, серы и угля. Открытие, изменившее цивилизации.",
     "gameEffects": ["explosive", "propellant", "signal_flare"]
+  },
+
+  {
+    "id": "NH3", "formula": "NH₃", "name": "Ammonia", "nameRu": "Аммиак",
+    "mass": 17.031, "state": "gas", "color": "#aaccff",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Pungent gas. Key to fertilizer production (Haber process). Essential biological nitrogen carrier.",
+    "descriptionRu": "Едкий газ. Основа производства удобрений (процесс Габера). Важнейший биологический переносчик азота.",
+    "gameEffects": ["fertilizer", "cleaning", "refrigerant"]
+  },
+  {
+    "id": "HF", "formula": "HF", "name": "Hydrofluoric Acid", "nameRu": "Плавиковая кислота",
+    "mass": 20.006, "state": "liquid", "color": "#ccff66",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": true, "basic": false, "oxidizer": false, "corrosive": true },
+    "description": "Etches glass! One of the most dangerous acids — penetrates skin and attacks bones.",
+    "descriptionRu": "Растворяет стекло! Одна из опаснейших кислот — проникает через кожу и разрушает кости.",
+    "gameEffects": ["glass_etching", "damage", "dissolve_stone"]
+  },
+  {
+    "id": "HBr", "formula": "HBr", "name": "Hydrobromic Acid", "nameRu": "Бромоводородная кислота",
+    "mass": 80.912, "state": "liquid", "color": "#cc6633",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": true, "basic": false, "oxidizer": false, "corrosive": true },
+    "description": "Strong acid formed from hydrogen and bromine. Stronger than HCl.",
+    "descriptionRu": "Сильная кислота из водорода и брома. Сильнее соляной кислоты.",
+    "gameEffects": ["dissolve_metal", "damage"]
+  },
+  {
+    "id": "HI", "formula": "HI", "name": "Hydroiodic Acid", "nameRu": "Йодоводородная кислота",
+    "mass": 127.912, "state": "liquid", "color": "#993399",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": true, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Strongest of the hydrohalic acids. Powerful reducing agent.",
+    "descriptionRu": "Самая сильная из галогеноводородных кислот. Мощный восстановитель.",
+    "gameEffects": ["reducing_agent", "dissolve_metal"]
+  },
+  {
+    "id": "LiOH", "formula": "LiOH", "name": "Lithium Hydroxide", "nameRu": "Гидроксид лития",
+    "mass": 23.948, "state": "solid", "color": "#e8e8ff",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": true, "oxidizer": false, "corrosive": true },
+    "description": "Lightest alkali hydroxide. Used in spacecraft CO₂ scrubbers and lithium batteries.",
+    "descriptionRu": "Легчайший гидроксид щелочного металла. Используется для очистки воздуха на космических кораблях и в литиевых батареях.",
+    "gameEffects": ["co2_scrubber", "battery_material"]
+  },
+  {
+    "id": "LiCl", "formula": "LiCl", "name": "Lithium Chloride", "nameRu": "Хлорид лития",
+    "mass": 42.394, "state": "solid", "color": "#e0e0e0",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Extremely hygroscopic salt. Absorbs moisture from air. Used as desiccant.",
+    "descriptionRu": "Крайне гигроскопичная соль. Поглощает влагу из воздуха. Используется как осушитель.",
+    "gameEffects": ["desiccant", "dehumidifier"]
+  },
+  {
+    "id": "TiO2", "formula": "TiO₂", "name": "Titanium Dioxide", "nameRu": "Диоксид титана",
+    "mass": 79.866, "state": "solid", "color": "#ffffff",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Brilliant white pigment. UV blocker. Photocatalyst that breaks down pollutants in sunlight.",
+    "descriptionRu": "Ярко-белый пигмент. УФ-блокатор. Фотокатализатор, расщепляющий загрязнители на свету.",
+    "gameEffects": ["pigment", "sun_protection", "photocatalyst"]
+  },
+  {
+    "id": "Cr2O3", "formula": "Cr₂O₃", "name": "Chromium(III) Oxide", "nameRu": "Оксид хрома(III)",
+    "mass": 151.99, "state": "solid", "color": "#336633",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Deep green pigment. Extremely hard and heat-resistant. Used in armor and abrasives.",
+    "descriptionRu": "Насыщенный зелёный пигмент. Крайне твёрд и термостоек. Используется в броне и абразивах.",
+    "gameEffects": ["pigment", "armor_material", "abrasive"]
+  },
+  {
+    "id": "MnO2", "formula": "MnO₂", "name": "Manganese Dioxide", "nameRu": "Диоксид марганца",
+    "mass": 86.937, "state": "solid", "color": "#333333",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": true, "corrosive": false },
+    "description": "Natural catalyst and oxidizer. Key component of dry cell batteries. Accelerates many reactions.",
+    "descriptionRu": "Природный катализатор и окислитель. Ключевой компонент батареек. Ускоряет многие реакции.",
+    "gameEffects": ["catalyst", "battery_material", "oxidizer"]
+  },
+  {
+    "id": "CoO", "formula": "CoO", "name": "Cobalt(II) Oxide", "nameRu": "Оксид кобальта(II)",
+    "mass": 74.932, "state": "solid", "color": "#336699",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Deep blue compound. Used in pottery glazes since ancient Egypt. Magnetic.",
+    "descriptionRu": "Тёмно-синее соединение. Используется в керамических глазурях со времён Древнего Египта. Магнитно.",
+    "gameEffects": ["pigment", "magnetic"]
+  },
+  {
+    "id": "NiCl2", "formula": "NiCl₂", "name": "Nickel(II) Chloride", "nameRu": "Хлорид никеля(II)",
+    "mass": 129.60, "state": "solid", "color": "#00cc66",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Bright green salt. Key reagent in electroplating. Catalyst for organic reactions.",
+    "descriptionRu": "Ярко-зелёная соль. Ключевой реагент для гальванопокрытий. Катализатор органических реакций.",
+    "gameEffects": ["electroplating", "catalyst"]
+  },
+  {
+    "id": "As2O3", "formula": "As₂O₃", "name": "Arsenic Trioxide", "nameRu": "Оксид мышьяка(III)",
+    "mass": 197.841, "state": "solid", "color": "#f0f0f0",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "The 'King of Poisons'. Odorless, tasteless, lethal. Used as a rat poison for centuries.",
+    "descriptionRu": "«Король ядов». Без запаха, вкуса, смертелен. Веками использовался как крысиный яд.",
+    "gameEffects": ["deadly_poison", "rat_poison", "glass_clarifier"]
+  },
+  {
+    "id": "AgCl", "formula": "AgCl", "name": "Silver Chloride", "nameRu": "Хлорид серебра",
+    "mass": 143.321, "state": "solid", "color": "#e0e0e0",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "White solid that darkens in light (basis of photography). Antimicrobial wound dressing.",
+    "descriptionRu": "Белое вещество, темнеющее на свету (основа фотографии). Антимикробная раневая повязка.",
+    "gameEffects": ["photography", "antimicrobial", "light_sensor"]
+  },
+  {
+    "id": "BaO", "formula": "BaO", "name": "Barium Oxide", "nameRu": "Оксид бария",
+    "mass": 153.326, "state": "solid", "color": "#f5f5cc",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": true, "oxidizer": false, "corrosive": true },
+    "description": "Powerful desiccant and getter. Reacts violently with water. Produces green flame.",
+    "descriptionRu": "Мощный осушитель и геттер. Бурно реагирует с водой. Даёт зелёное пламя.",
+    "gameEffects": ["desiccant", "green_flame"]
+  },
+  {
+    "id": "WO3", "formula": "WO₃", "name": "Tungsten Trioxide", "nameRu": "Оксид вольфрама(VI)",
+    "mass": 231.84, "state": "solid", "color": "#cccc00",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Yellow powder. Electrochromic — changes color with voltage. Smart glass technology.",
+    "descriptionRu": "Жёлтый порошок. Электрохромный — меняет цвет при напряжении. Технология умного стекла.",
+    "gameEffects": ["smart_glass", "electrochromic", "pigment"]
+  },
+  {
+    "id": "PbO", "formula": "PbO", "name": "Lead(II) Oxide", "nameRu": "Оксид свинца(II)",
+    "mass": 223.2, "state": "solid", "color": "#cc9933",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Yellow-orange powder (litharge). Used in lead-acid batteries and ancient pottery glazes.",
+    "descriptionRu": "Жёлто-оранжевый порошок (глёт). Используется в свинцовых аккумуляторах и древних керамических глазурях.",
+    "gameEffects": ["battery_material", "pigment", "radiation_shield"]
+  },
+  {
+    "id": "PbS", "formula": "PbS", "name": "Lead(II) Sulfide", "nameRu": "Сульфид свинца (галенит)",
+    "mass": 239.27, "state": "solid", "color": "#333344",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Galena — the principal ore of lead. First semiconductor discovered. Used in early radio crystal detectors.",
+    "descriptionRu": "Галенит — основная руда свинца. Первый обнаруженный полупроводник. Применялся в ранних радиоприёмниках.",
+    "gameEffects": ["semiconductor", "radio_detector", "lead_source"]
+  },
+  {
+    "id": "Bi2O3", "formula": "Bi₂O₃", "name": "Bismuth Trioxide", "nameRu": "Оксид висмута(III)",
+    "mass": 465.959, "state": "solid", "color": "#ffffcc",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Yellow powder with medicinal properties. Active ingredient in stomach remedies. Low toxicity.",
+    "descriptionRu": "Жёлтый порошок с лечебными свойствами. Действующее вещество желудочных средств. Малотоксичен.",
+    "gameEffects": ["medicine", "stomach_remedy", "pigment"]
+  },
+  {
+    "id": "UO2", "formula": "UO₂", "name": "Uranium Dioxide", "nameRu": "Диоксид урана",
+    "mass": 270.028, "state": "solid", "color": "#333300",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Nuclear fuel. Incredibly dense. A single pellet contains energy equivalent to a tonne of coal.",
+    "descriptionRu": "Ядерное топливо. Невероятно плотный. Один стержень содержит энергию, эквивалентную тонне угля.",
+    "gameEffects": ["nuclear_fuel", "energy_source", "radiation"]
+  },
+  {
+    "id": "CH3COOH", "formula": "CH₃COOH", "name": "Acetic Acid", "nameRu": "Уксусная кислота",
+    "mass": 60.052, "state": "liquid", "color": "#eeeedd",
+    "properties": { "flammable": true, "toxic": false, "explosive": false, "acidic": true, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Vinegar. Natural product of fermentation. Solvent, preservative, and creature bait.",
+    "descriptionRu": "Уксус. Природный продукт брожения. Растворитель, консервант и приманка для существ.",
+    "gameEffects": ["solvent", "preservative", "creature_bait", "descaler"]
+  },
+  {
+    "id": "C6H12O6", "formula": "C₆H₁₂O₆", "name": "Glucose", "nameRu": "Глюкоза",
+    "mass": 180.156, "state": "solid", "color": "#ffffee",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Simple sugar. Universal biological fuel. Feed to microorganisms or use as fast energy source.",
+    "descriptionRu": "Простой сахар. Универсальное биологическое топливо. Корм для микроорганизмов или быстрый источник энергии.",
+    "gameEffects": ["energy_food", "microorganism_feed", "fermentation_base"]
+  },
+
+  {
+    "id": "H2S", "formula": "H₂S", "name": "Hydrogen Sulfide", "nameRu": "Сероводород",
+    "mass": 34.08, "state": "gas", "color": "#cccc66",
+    "properties": { "flammable": true, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Rotten egg smell. Toxic in high concentrations. Natural hot spring emission.",
+    "descriptionRu": "Запах тухлых яиц. Токсичен в высоких концентрациях. Газ горячих источников.",
+    "gameEffects": ["poison_gas", "indicator", "hot_spring"]
+  },
+  {
+    "id": "H2SO4", "formula": "H₂SO₄", "name": "Sulfuric Acid", "nameRu": "Серная кислота",
+    "mass": 98.079, "state": "liquid", "color": "#ffee00",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": true, "basic": false, "oxidizer": true, "corrosive": true },
+    "description": "King of chemicals. Most produced chemical worldwide. Violently exothermic with water.",
+    "descriptionRu": "Царь химикатов. Самое производимое химическое вещество в мире. Бурно реагирует с водой.",
+    "gameEffects": ["dissolve_metal", "dissolve_organic", "battery_acid", "damage"]
+  },
+  {
+    "id": "HNO3", "formula": "HNO₃", "name": "Nitric Acid", "nameRu": "Азотная кислота",
+    "mass": 63.012, "state": "liquid", "color": "#ff6600",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": true, "basic": false, "oxidizer": true, "corrosive": true },
+    "description": "Fuming corrosive acid. Dissolves most metals. Component of aqua regia (with HCl) to dissolve gold.",
+    "descriptionRu": "Дымящая кислота. Растворяет большинство металлов. Компонент царской водки (с HCl) для растворения золота.",
+    "gameEffects": ["dissolve_metal", "oxidizer", "damage", "aqua_regia_component"]
+  },
+  {
+    "id": "CuO", "formula": "CuO", "name": "Copper(II) Oxide", "nameRu": "Оксид меди(II)",
+    "mass": 79.545, "state": "solid", "color": "#1a1a1a",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Black powder. Reducible by carbon or hydrogen — ancient copper smelting.",
+    "descriptionRu": "Чёрный порошок. Восстанавливается углеродом или водородом — древняя медеплавка.",
+    "gameEffects": ["pigment", "smelting_ore", "catalyst"]
+  },
+  {
+    "id": "NaF", "formula": "NaF", "name": "Sodium Fluoride", "nameRu": "Фторид натрия",
+    "mass": 41.988, "state": "solid", "color": "#f0f0f0",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Active ingredient in toothpaste. Strengthens tooth enamel. Toxic in large doses.",
+    "descriptionRu": "Активный компонент зубной пасты. Укрепляет зубную эмаль. Токсичен в больших дозах.",
+    "gameEffects": ["dental_protection", "water_treatment"]
+  },
+  {
+    "id": "NaBr", "formula": "NaBr", "name": "Sodium Bromide", "nameRu": "Бромид натрия",
+    "mass": 102.894, "state": "solid", "color": "#e8e8e8",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "White crystalline salt. Historical sedative and anticonvulsant. Photography reagent.",
+    "descriptionRu": "Белая кристаллическая соль. Исторический седативный и противосудорожный препарат.",
+    "gameEffects": ["sedative", "photography"]
+  },
+  {
+    "id": "KF", "formula": "KF", "name": "Potassium Fluoride", "nameRu": "Фторид калия",
+    "mass": 58.097, "state": "solid", "color": "#e0e0e0",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": true },
+    "description": "Strong fluorinating agent. Used in organic synthesis. Corrosive.",
+    "descriptionRu": "Сильный фторирующий агент. Используется в органическом синтезе. Едкий.",
+    "gameEffects": ["fluorinating_agent"]
+  },
+  {
+    "id": "KBr", "formula": "KBr", "name": "Potassium Bromide", "nameRu": "Бромид калия",
+    "mass": 119.002, "state": "solid", "color": "#e0e0e0",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Photography essential. Historical anticonvulsant medicine. Transparent to infrared.",
+    "descriptionRu": "Необходим для фотографии. Исторический противосудорожный препарат. Прозрачен для инфракрасного.",
+    "gameEffects": ["photography", "medicine", "optics"]
+  },
+  {
+    "id": "AgBr", "formula": "AgBr", "name": "Silver Bromide", "nameRu": "Бромид серебра",
+    "mass": 187.772, "state": "solid", "color": "#e8e8cc",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Pale yellow, darkens in light. The basis of photographic film. More light-sensitive than AgCl.",
+    "descriptionRu": "Бледно-жёлтый, темнеет на свету. Основа фотоплёнки. Светочувствительнее AgCl.",
+    "gameEffects": ["photography", "light_sensor"]
+  },
+  {
+    "id": "NH4Cl", "formula": "NH₄Cl", "name": "Ammonium Chloride", "nameRu": "Хлорид аммония",
+    "mass": 53.491, "state": "solid", "color": "#f5f5f5",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Sal ammoniac. White smoke when heated. Used in batteries, flux, and cough medicine.",
+    "descriptionRu": "Нашатырь. Белый дым при нагревании. Используется в батарейках, флюсе и от кашля.",
+    "gameEffects": ["flux", "battery_material", "smoke_screen"]
+  },
+  {
+    "id": "MgCl2", "formula": "MgCl₂", "name": "Magnesium Chloride", "nameRu": "Хлорид магния",
+    "mass": 95.211, "state": "solid", "color": "#e0e0e0",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "De-icing salt. Dust suppressant. Source of magnesium metal via electrolysis.",
+    "descriptionRu": "Противогололёдная соль. Подавитель пыли. Источник металлического магния через электролиз.",
+    "gameEffects": ["de_icing", "dust_control", "magnesium_source"]
+  },
+  {
+    "id": "CaCl2", "formula": "CaCl₂", "name": "Calcium Chloride", "nameRu": "Хлорид кальция",
+    "mass": 110.984, "state": "solid", "color": "#f0f0f0",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Powerful desiccant and de-icer. Exothermic when dissolved — can melt ice below -50°C.",
+    "descriptionRu": "Мощный осушитель и антигололёдный реагент. Экзотермичен при растворении — плавит лёд ниже -50°C.",
+    "gameEffects": ["desiccant", "de_icing", "heat_source"]
+  },
+  {
+    "id": "BaCl2", "formula": "BaCl₂", "name": "Barium Chloride", "nameRu": "Хлорид бария",
+    "mass": 208.233, "state": "solid", "color": "#f0f0f0",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Toxic barium salt. Burns with characteristic green flame. Chemical analysis reagent.",
+    "descriptionRu": "Токсичная соль бария. Горит характерным зелёным пламенем. Реагент для химического анализа.",
+    "gameEffects": ["green_flame", "analysis_reagent"]
+  },
+  {
+    "id": "FeCl3", "formula": "FeCl₃", "name": "Iron(III) Chloride", "nameRu": "Хлорид железа(III)",
+    "mass": 162.204, "state": "solid", "color": "#663300",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": true },
+    "description": "Dark brown, corrosive. Etches copper (circuit boards). Water purification agent.",
+    "descriptionRu": "Тёмно-коричневый, едкий. Травит медь (печатные платы). Реагент для очистки воды.",
+    "gameEffects": ["copper_etching", "water_purification", "coagulant"]
+  },
+  {
+    "id": "CuCl2", "formula": "CuCl₂", "name": "Copper(II) Chloride", "nameRu": "Хлорид меди(II)",
+    "mass": 134.452, "state": "solid", "color": "#006633",
+    "properties": { "flammable": false, "toxic": true, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Bright green crystals. Turns blue in water. Catalyst. Gives green-blue flame.",
+    "descriptionRu": "Ярко-зелёные кристаллы. Синеет в воде. Катализатор. Даёт зелёно-голубое пламя.",
+    "gameEffects": ["catalyst", "pigment", "blue_green_flame"]
+  },
+  {
+    "id": "FeCl2", "formula": "FeCl₂", "name": "Iron(II) Chloride", "nameRu": "Хлорид железа(II)",
+    "mass": 126.751, "state": "solid", "color": "#669966",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": false },
+    "description": "Greenish solid. Product of iron dissolved in HCl. Reducing agent.",
+    "descriptionRu": "Зеленоватое твёрдое вещество. Продукт растворения железа в HCl. Восстановитель.",
+    "gameEffects": ["reducing_agent", "water_treatment"]
+  },
+  {
+    "id": "ZnCl2", "formula": "ZnCl₂", "name": "Zinc Chloride", "nameRu": "Хлорид цинка",
+    "mass": 136.286, "state": "solid", "color": "#e0e0e0",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": false, "oxidizer": false, "corrosive": true },
+    "description": "Powerful flux for soldering. Dehydrating agent. Used in fireproofing fabric.",
+    "descriptionRu": "Мощный флюс для пайки. Обезвоживающий агент. Огнезащита тканей.",
+    "gameEffects": ["flux", "desiccant", "fireproofing"]
+  },
+  {
+    "id": "Na2O", "formula": "Na₂O", "name": "Sodium Oxide", "nameRu": "Оксид натрия",
+    "mass": 61.979, "state": "solid", "color": "#f5f5f5",
+    "properties": { "flammable": false, "toxic": false, "explosive": false, "acidic": false, "basic": true, "oxidizer": false, "corrosive": true },
+    "description": "White powder. Reacts violently with water to form NaOH. Key component in glass making.",
+    "descriptionRu": "Белый порошок. Бурно реагирует с водой, образуя NaOH. Ключевой компонент стекловарения.",
+    "gameEffects": ["glass_making", "caustic"]
   }
 ]

src/data/creatures.json

@@ -0,0 +1,335 @@
+[
+  {
+    "id": "crystallid",
+    "name": "Crystallid",
+    "nameRu": "Кристаллид",
+    "speciesId": 0,
+    "biome": "catalytic-wastes",
+    "description": "Slow, armored creature that feeds on mineral deposits. Its silicon-rich body refracts light into prismatic patterns. When killed, it shatters into valuable crystalline fragments.",
+    "descriptionRu": "Медленное бронированное существо, питающееся минеральными отложениями. Его кремниевое тело преломляет свет в призматические узоры. При гибели рассыпается на ценные кристаллические осколки.",
+    "color": "#88ccff",
+    "radius": 10,
+    "radiusYouth": 6,
+    "health": 120,
+    "speed": 30,
+    "damage": 8,
+    "armor": 0.3,
+    "diet": "mineral",
+    "dietTiles": ["mineral-vein", "crystal-formation"],
+    "excretionElement": 14,
+    "energyMax": 100,
+    "energyPerFeed": 25,
+    "energyDrainPerSecond": 1.5,
+    "hungerThreshold": 0.4,
+    "aggressionRadius": 0,
+    "fleeRadius": 80,
+    "wanderRadius": 200,
+    "attackRange": 20,
+    "attackCooldown": 2000,
+    "eggDuration": 8000,
+    "youthDuration": 15000,
+    "matureDuration": 60000,
+    "agingDuration": 20000,
+    "reproductionEnergy": 60,
+    "offspringCount": 2,
+    "maxPopulation": 12,
+    "spawnWeight": 0.4,
+    "preferredTiles": ["ground", "scorched-earth"]
+  },
+  {
+    "id": "acidophile",
+    "name": "Acidophile",
+    "nameRu": "Ацидофил",
+    "speciesId": 1,
+    "biome": "catalytic-wastes",
+    "description": "Mid-sized creature that thrives in acidic environments. Consumes mineral deposits and excretes hydrochloric acid, gradually reshaping the landscape. Territorial but not predatory.",
+    "descriptionRu": "Среднеразмерное существо, процветающее в кислотной среде. Поглощает минералы и выделяет соляную кислоту, постепенно изменяя ландшафт. Территориальное, но не хищное.",
+    "color": "#44ff44",
+    "radius": 8,
+    "radiusYouth": 5,
+    "health": 80,
+    "speed": 50,
+    "damage": 12,
+    "armor": 0.1,
+    "diet": "mineral",
+    "dietTiles": ["mineral-vein", "geyser"],
+    "excretionElement": 17,
+    "energyMax": 80,
+    "energyPerFeed": 20,
+    "energyDrainPerSecond": 2.0,
+    "hungerThreshold": 0.5,
+    "aggressionRadius": 100,
+    "fleeRadius": 120,
+    "wanderRadius": 250,
+    "attackRange": 24,
+    "attackCooldown": 1500,
+    "eggDuration": 6000,
+    "youthDuration": 12000,
+    "matureDuration": 45000,
+    "agingDuration": 15000,
+    "reproductionEnergy": 50,
+    "offspringCount": 3,
+    "maxPopulation": 15,
+    "spawnWeight": 0.35,
+    "preferredTiles": ["acid-shallow", "ground"]
+  },
+  {
+    "id": "reagent",
+    "name": "Reagent",
+    "nameRu": "Реагент",
+    "speciesId": 2,
+    "biome": "catalytic-wastes",
+    "description": "Fast, aggressive predator that hunts in pairs. Contains unstable chemical compounds — when two Reagents collide, they trigger an exothermic reaction. Feeds on other creatures.",
+    "descriptionRu": "Быстрый агрессивный хищник, охотящийся парами. Содержит нестабильные химические соединения — при столкновении двух Реагентов происходит экзотермическая реакция. Питается другими существами.",
+    "color": "#ff4444",
+    "radius": 7,
+    "radiusYouth": 4,
+    "health": 60,
+    "speed": 80,
+    "damage": 20,
+    "armor": 0.0,
+    "diet": "creature",
+    "dietTiles": [],
+    "excretionElement": 0,
+    "energyMax": 60,
+    "energyPerFeed": 30,
+    "energyDrainPerSecond": 3.0,
+    "hungerThreshold": 0.6,
+    "aggressionRadius": 150,
+    "fleeRadius": 60,
+    "wanderRadius": 300,
+    "attackRange": 18,
+    "attackCooldown": 1000,
+    "eggDuration": 5000,
+    "youthDuration": 10000,
+    "matureDuration": 35000,
+    "agingDuration": 12000,
+    "reproductionEnergy": 40,
+    "offspringCount": 1,
+    "maxPopulation": 8,
+    "spawnWeight": 0.25,
+    "preferredTiles": ["scorched-earth", "ground"]
+  },
+  {
+    "id": "pendulum",
+    "name": "Pendulum",
+    "nameRu": "Маятник",
+    "speciesId": 3,
+    "biome": "kinetic-mountains",
+    "description": "Flying creature with strictly periodic motion. Swings back and forth on invisible pivot points. Can be used as a clock or platform. Docile unless struck mid-swing.",
+    "descriptionRu": "Летающее существо со строго периодичным движением. Качается взад-вперёд на невидимых опорных точках. Можно использовать как часы или платформу. Мирное, если не ударить в полёте.",
+    "color": "#77aadd",
+    "radius": 9,
+    "radiusYouth": 5,
+    "health": 90,
+    "speed": 60,
+    "damage": 10,
+    "armor": 0.15,
+    "diet": "mineral",
+    "dietTiles": ["ore-deposit", "gear-floor"],
+    "excretionElement": 26,
+    "energyMax": 90,
+    "energyPerFeed": 22,
+    "energyDrainPerSecond": 1.8,
+    "hungerThreshold": 0.45,
+    "aggressionRadius": 0,
+    "fleeRadius": 100,
+    "wanderRadius": 220,
+    "attackRange": 22,
+    "attackCooldown": 1800,
+    "eggDuration": 7000,
+    "youthDuration": 14000,
+    "matureDuration": 55000,
+    "agingDuration": 18000,
+    "reproductionEnergy": 55,
+    "offspringCount": 2,
+    "maxPopulation": 10,
+    "spawnWeight": 0.4,
+    "preferredTiles": ["bare-rock", "gear-floor"]
+  },
+  {
+    "id": "mechanoid",
+    "name": "Mechanoid",
+    "nameRu": "Механоид",
+    "speciesId": 4,
+    "biome": "kinetic-mountains",
+    "description": "Half-living automaton. Can be repaired, reprogrammed, or scavenged for metal parts. Patrols ancient machinery and attacks intruders near gear mechanisms.",
+    "descriptionRu": "Полуживой автомат. Можно починить, перепрограммировать или разобрать на металлические детали. Патрулирует древние механизмы и атакует чужаков у шестерёнок.",
+    "color": "#aaaacc",
+    "radius": 11,
+    "radiusYouth": 7,
+    "health": 150,
+    "speed": 35,
+    "damage": 18,
+    "armor": 0.4,
+    "diet": "mineral",
+    "dietTiles": ["ore-deposit"],
+    "excretionElement": 29,
+    "energyMax": 120,
+    "energyPerFeed": 30,
+    "energyDrainPerSecond": 1.0,
+    "hungerThreshold": 0.3,
+    "aggressionRadius": 120,
+    "fleeRadius": 0,
+    "wanderRadius": 150,
+    "attackRange": 26,
+    "attackCooldown": 2200,
+    "eggDuration": 10000,
+    "youthDuration": 18000,
+    "matureDuration": 80000,
+    "agingDuration": 25000,
+    "reproductionEnergy": 70,
+    "offspringCount": 1,
+    "maxPopulation": 8,
+    "spawnWeight": 0.3,
+    "preferredTiles": ["gear-floor", "iron-ridge"]
+  },
+  {
+    "id": "resonator",
+    "name": "Resonator",
+    "nameRu": "Резонатор",
+    "speciesId": 5,
+    "biome": "kinetic-mountains",
+    "description": "Vibrates at fixed frequencies. Dangerous if its frequency matches your gear — resonance shatters equipment. Can be used to break barriers or stun other creatures.",
+    "descriptionRu": "Вибрирует на фиксированных частотах. Опасен, если его частота совпадает с вашим снаряжением — резонанс разрушает оборудование. Может ломать барьеры или оглушать существ.",
+    "color": "#ff88ff",
+    "radius": 7,
+    "radiusYouth": 4,
+    "health": 50,
+    "speed": 70,
+    "damage": 25,
+    "armor": 0.0,
+    "diet": "creature",
+    "dietTiles": [],
+    "excretionElement": 0,
+    "energyMax": 55,
+    "energyPerFeed": 25,
+    "energyDrainPerSecond": 2.8,
+    "hungerThreshold": 0.55,
+    "aggressionRadius": 130,
+    "fleeRadius": 70,
+    "wanderRadius": 280,
+    "attackRange": 20,
+    "attackCooldown": 1200,
+    "eggDuration": 5000,
+    "youthDuration": 10000,
+    "matureDuration": 40000,
+    "agingDuration": 13000,
+    "reproductionEnergy": 35,
+    "offspringCount": 1,
+    "maxPopulation": 6,
+    "spawnWeight": 0.3,
+    "preferredTiles": ["magnetic-field", "bare-rock"]
+  },
+  {
+    "id": "symbiote",
+    "name": "Symbiote",
+    "nameRu": "Симбионт",
+    "speciesId": 6,
+    "biome": "verdant-forests",
+    "description": "Always appears in bonded pairs. Separating them weakens both — one may die without the other. Feeds on forest floor decomposition. Peaceful but resilient in pairs.",
+    "descriptionRu": "Всегда появляется связанными парами. Разделение ослабляет обоих — один может погибнуть без другого. Питается лесной подстилкой. Мирные, но в паре стойкие.",
+    "color": "#44ddaa",
+    "radius": 8,
+    "radiusYouth": 5,
+    "health": 70,
+    "speed": 45,
+    "damage": 6,
+    "armor": 0.2,
+    "diet": "mineral",
+    "dietTiles": ["herb-patch", "mycelium-carpet"],
+    "excretionElement": 7,
+    "energyMax": 85,
+    "energyPerFeed": 20,
+    "energyDrainPerSecond": 1.6,
+    "hungerThreshold": 0.4,
+    "aggressionRadius": 0,
+    "fleeRadius": 90,
+    "wanderRadius": 180,
+    "attackRange": 18,
+    "attackCooldown": 2000,
+    "eggDuration": 7000,
+    "youthDuration": 13000,
+    "matureDuration": 50000,
+    "agingDuration": 17000,
+    "reproductionEnergy": 45,
+    "offspringCount": 2,
+    "maxPopulation": 14,
+    "spawnWeight": 0.4,
+    "preferredTiles": ["forest-floor", "dense-undergrowth"]
+  },
+  {
+    "id": "mimic",
+    "name": "Mimic",
+    "nameRu": "Мимикр",
+    "speciesId": 7,
+    "biome": "verdant-forests",
+    "description": "Master of disguise. Can appear as a plant, resource, or even a fungal node. Only reveals itself when approached too closely. Ambush predator with potent venom.",
+    "descriptionRu": "Мастер маскировки. Может выглядеть как растение, ресурс или грибной узел. Раскрывает себя только при близком приближении. Засадный хищник с мощным ядом.",
+    "color": "#33cc33",
+    "radius": 8,
+    "radiusYouth": 5,
+    "health": 65,
+    "speed": 55,
+    "damage": 22,
+    "armor": 0.05,
+    "diet": "creature",
+    "dietTiles": [],
+    "excretionElement": 0,
+    "energyMax": 65,
+    "energyPerFeed": 28,
+    "energyDrainPerSecond": 2.2,
+    "hungerThreshold": 0.5,
+    "aggressionRadius": 60,
+    "fleeRadius": 80,
+    "wanderRadius": 200,
+    "attackRange": 16,
+    "attackCooldown": 1400,
+    "eggDuration": 6000,
+    "youthDuration": 11000,
+    "matureDuration": 42000,
+    "agingDuration": 14000,
+    "reproductionEnergy": 42,
+    "offspringCount": 1,
+    "maxPopulation": 7,
+    "spawnWeight": 0.25,
+    "preferredTiles": ["forest-floor", "mycelium-carpet"]
+  },
+  {
+    "id": "spore-bearer",
+    "name": "Spore-bearer",
+    "nameRu": "Споровик",
+    "speciesId": 8,
+    "biome": "verdant-forests",
+    "description": "Fungal creature, avatar of the Mycelium. Peaceful and slow. If harmed, the entire forest turns hostile. Deposits knowledge into fungal nodes when passing near them.",
+    "descriptionRu": "Грибное существо, аватар Мицелия. Мирное и медленное. Если обидеть — весь лес становится враждебным. Откладывает знания в грибные узлы, проходя мимо них.",
+    "color": "#9966cc",
+    "radius": 12,
+    "radiusYouth": 7,
+    "health": 200,
+    "speed": 20,
+    "damage": 5,
+    "armor": 0.25,
+    "diet": "mineral",
+    "dietTiles": ["mycelium-carpet", "herb-patch"],
+    "excretionElement": 15,
+    "energyMax": 150,
+    "energyPerFeed": 35,
+    "energyDrainPerSecond": 0.8,
+    "hungerThreshold": 0.3,
+    "aggressionRadius": 0,
+    "fleeRadius": 60,
+    "wanderRadius": 160,
+    "attackRange": 24,
+    "attackCooldown": 3000,
+    "eggDuration": 12000,
+    "youthDuration": 20000,
+    "matureDuration": 90000,
+    "agingDuration": 30000,
+    "reproductionEnergy": 80,
+    "offspringCount": 1,
+    "maxPopulation": 5,
+    "spawnWeight": 0.35,
+    "preferredTiles": ["mycelium-carpet", "forest-floor"]
+  }
+]

src/data/cycle-narrative.json

@@ -0,0 +1,97 @@
+{
+  "themes": {
+    "awakening": {
+      "name": "Awakening",
+      "nameRu": "Пробуждение",
+      "description": "You are learning the world. Everything is new, mysterious, dangerous.",
+      "descriptionRu": "Ты познаёшь мир. Всё ново, загадочно, опасно.",
+      "cradleQuote": "...the first breath of a new cycle...",
+      "cradleQuoteRu": "...первый вдох нового цикла...",
+      "loreFrag": [
+        { "text": "The world breathes. You are its newest thought.", "textRu": "Мир дышит. Ты — его новейшая мысль." },
+        { "text": "Each atom you touch remembers being touched before.", "textRu": "Каждый атом, которого ты касаешься, помнит прежние прикосновения." },
+        { "text": "The cycle begins. As it always does. As it always will.", "textRu": "Цикл начинается. Как всегда. Как будет всегда." }
+      ]
+    },
+    "doubt": {
+      "name": "Doubt",
+      "nameRu": "Сомнение",
+      "description": "You find traces of past Adepts. Were they... you?",
+      "descriptionRu": "Ты находишь следы прошлых Адептов. Были ли они... тобой?",
+      "cradleQuote": "...something stirs in the mycelium. Familiar...",
+      "cradleQuoteRu": "...что-то шевелится в мицелии. Знакомое...",
+      "loreFrag": [
+        { "text": "Ruins that look like they were built by your hands.", "textRu": "Руины, словно построенные твоими руками." },
+        { "text": "The handwriting in this journal... is it yours?", "textRu": "Почерк в этом дневнике... он твой?" },
+        { "text": "I have been here before. Or someone exactly like me.", "textRu": "Я уже был здесь. Или кто-то точно такой же, как я." }
+      ]
+    },
+    "realization": {
+      "name": "Realization",
+      "nameRu": "Осознание",
+      "description": "You begin to understand the nature of cycles.",
+      "descriptionRu": "Ты начинаешь понимать природу циклов.",
+      "cradleQuote": "...the pattern becomes visible...",
+      "cradleQuoteRu": "...паттерн становится видимым...",
+      "loreFrag": [
+        { "text": "The cycle is not a prison. It is a spiral.", "textRu": "Цикл — не тюрьма. Это спираль." },
+        { "text": "Each death is a transformation, not an ending.", "textRu": "Каждая смерть — трансформация, не конец." },
+        { "text": "The Mycelium knew all along. It was waiting for you to see.", "textRu": "Мицелий знал с самого начала. Он ждал, пока ты увидишь." }
+      ]
+    },
+    "attempt": {
+      "name": "Attempt",
+      "nameRu": "Попытка",
+      "description": "First attempts to transcend the cycle.",
+      "descriptionRu": "Первые попытки трансцендировать цикл.",
+      "cradleQuote": "...can the cycle be broken? Or only understood?...",
+      "cradleQuoteRu": "...можно ли разорвать цикл? Или только понять?...",
+      "loreFrag": [
+        { "text": "The Synthetics tried to break free. They shattered reality instead.", "textRu": "Синтетики пытались вырваться. Вместо этого разбили реальность." },
+        { "text": "To transcend is not to escape. It is to encompass.", "textRu": "Трансцендировать — не значит сбежать. Это значит объять." },
+        { "text": "The harder you push against the cycle, the tighter it holds.", "textRu": "Чем сильнее давишь на цикл, тем крепче он держит." }
+      ]
+    },
+    "acceptance": {
+      "name": "Acceptance",
+      "nameRu": "Принятие",
+      "description": "The cycle is not a prison but a form of being.",
+      "descriptionRu": "Цикл — не тюрьма, а форма бытия.",
+      "cradleQuote": "...you are not stuck IN the cycle. You ARE the cycle...",
+      "cradleQuoteRu": "...ты не застрял В цикле. Ты И ЕСТЬ цикл...",
+      "loreFrag": [
+        { "text": "An atom does not resent its orbit. A wave does not fight its shore.", "textRu": "Атом не злится на свою орбиту. Волна не борется со своим берегом." },
+        { "text": "The only way out is through. And through. And through.", "textRu": "Единственный выход — насквозь. И насквозь. И насквозь." },
+        { "text": "Every cycle slightly different. Every cycle slightly closer.", "textRu": "Каждый цикл чуть другой. Каждый цикл чуть ближе." }
+      ]
+    },
+    "synthesis": {
+      "name": "Synthesis",
+      "nameRu": "Синтез",
+      "description": "All knowledge unifies. The cycle does not break — it transcends.",
+      "descriptionRu": "Всё знание объединяется. Цикл не ломается — трансцендирует.",
+      "cradleQuote": "...when all fragments connect, something new emerges...",
+      "cradleQuoteRu": "...когда все фрагменты соединяются, рождается новое...",
+      "loreFrag": [
+        { "text": "Synthesis is not creation. It is transformation.", "textRu": "Синтез — не создание. Это трансформация." },
+        { "text": "You have become what the Synthetics could not: a living cycle.", "textRu": "Ты стал тем, чем Синтетики не смогли: живым циклом." },
+        { "text": "The Law of Synthesis: when all fragments connect, the cycle transcends.", "textRu": "Закон Синтеза: когда все фрагменты знания соединяются, цикл трансцендирует." }
+      ]
+    }
+  },
+  "renewalMessages": [
+    { "text": "The Great Renewal washes over the world...", "textRu": "Великое Обновление окатывает мир..." },
+    { "text": "Seven lives. Seven deaths. The cycle turns.", "textRu": "Семь жизней. Семь смертей. Цикл поворачивается." },
+    { "text": "The Mycelium pulses. A new age begins.", "textRu": "Мицелий пульсирует. Начинается новая эпоха." }
+  ],
+  "traceMessages": {
+    "death_site": [
+      { "text": "Here an adept fell... elements returning to the earth.", "textRu": "Здесь пал адепт... элементы возвращаются в землю." },
+      { "text": "A mark of dissolution. Someone ended their cycle here.", "textRu": "Знак растворения. Кто-то завершил свой цикл здесь." }
+    ],
+    "discovery_site": [
+      { "text": "Traces of experimentation linger in this place.", "textRu": "Следы экспериментов витают в этом месте." },
+      { "text": "The soil remembers a reaction that happened here.", "textRu": "Почва помнит реакцию, произошедшую здесь." }
+    ]
+  }
+}

src/data/elements.json

@@ -25,6 +25,32 @@
     "description": "Noble gas. Completely inert — refuses to react with anything. Lighter than air.",
     "descriptionRu": "Благородный газ. Абсолютно инертен — не реагирует ни с чем. Легче воздуха."
   },
+  {
+    "symbol": "Li",
+    "name": "Lithium",
+    "nameRu": "Литий",
+    "atomicNumber": 3,
+    "atomicMass": 6.941,
+    "electronegativity": 0.98,
+    "category": "alkali-metal",
+    "state": "solid",
+    "color": "#cc80ff",
+    "description": "Lightest metal. Soft enough to cut with a knife. Key component of modern batteries. Burns crimson red.",
+    "descriptionRu": "Легчайший металл. Настолько мягкий, что режется ножом. Ключевой компонент современных аккумуляторов. Горит малиновым пламенем."
+  },
+  {
+    "symbol": "B",
+    "name": "Boron",
+    "nameRu": "Бор",
+    "atomicNumber": 5,
+    "atomicMass": 10.811,
+    "electronegativity": 2.04,
+    "category": "metalloid",
+    "state": "solid",
+    "color": "#ffb5b5",
+    "description": "Hard metalloid. Essential for borosilicate glass (heat-resistant). Boron compounds are used as neutron absorbers.",
+    "descriptionRu": "Твёрдый металлоид. Основа боросиликатного стекла (термостойкого). Соединения бора поглощают нейтроны."
+  },
   {
     "symbol": "C",
     "name": "Carbon",
@@ -64,6 +90,32 @@
     "description": "Essential for combustion and respiration. Highly reactive oxidizer. 21% of air.",
     "descriptionRu": "Необходим для горения и дыхания. Сильный окислитель. 21% воздуха."
   },
+  {
+    "symbol": "F",
+    "name": "Fluorine",
+    "nameRu": "Фтор",
+    "atomicNumber": 9,
+    "atomicMass": 18.998,
+    "electronegativity": 3.98,
+    "category": "halogen",
+    "state": "gas",
+    "color": "#90e050",
+    "description": "Most reactive element in existence. Attacks almost everything, even glass. Handle with extreme caution.",
+    "descriptionRu": "Самый реактивный элемент в природе. Атакует почти всё, даже стекло. Обращаться с предельной осторожностью."
+  },
+  {
+    "symbol": "Ne",
+    "name": "Neon",
+    "nameRu": "Неон",
+    "atomicNumber": 10,
+    "atomicMass": 20.180,
+    "electronegativity": 0,
+    "category": "noble-gas",
+    "state": "gas",
+    "color": "#b3e3f5",
+    "description": "Noble gas. Produces iconic red-orange glow in discharge tubes. Completely inert.",
+    "descriptionRu": "Благородный газ. Даёт культовое красно-оранжевое свечение в газоразрядных трубках. Полностью инертен."
+  },
   {
     "symbol": "Na",
     "name": "Sodium",
@@ -155,6 +207,19 @@
     "description": "Toxic yellow-green gas. Powerful disinfectant. Combines readily with metals to form salts.",
     "descriptionRu": "Ядовитый жёлто-зелёный газ. Мощный дезинфектант. Легко соединяется с металлами, образуя соли."
   },
+  {
+    "symbol": "Ar",
+    "name": "Argon",
+    "nameRu": "Аргон",
+    "atomicNumber": 18,
+    "atomicMass": 39.948,
+    "electronegativity": 0,
+    "category": "noble-gas",
+    "state": "gas",
+    "color": "#80d1e3",
+    "description": "Third most abundant gas in atmosphere (0.93%). Used as shielding gas in welding. Completely inert.",
+    "descriptionRu": "Третий по распространённости газ в атмосфере (0,93%). Защитный газ при сварке. Полностью инертен."
+  },
   {
     "symbol": "K",
     "name": "Potassium",
@@ -181,6 +246,45 @@
     "description": "Essential for bones and shells. Reacts with water, but less violently than sodium. Component of limestone and cement.",
     "descriptionRu": "Необходим для костей и раковин. Реагирует с водой, но менее бурно, чем натрий. Компонент известняка и цемента."
   },
+  {
+    "symbol": "Ti",
+    "name": "Titanium",
+    "nameRu": "Титан",
+    "atomicNumber": 22,
+    "atomicMass": 47.867,
+    "electronegativity": 1.54,
+    "category": "transition-metal",
+    "state": "solid",
+    "color": "#bfc2c7",
+    "description": "Strong as steel but 45% lighter. Corrosion-resistant. Used in aerospace, implants, and armor.",
+    "descriptionRu": "Прочен как сталь, но на 45% легче. Коррозионностойкий. Применяется в авиации, имплантах и броне."
+  },
+  {
+    "symbol": "Cr",
+    "name": "Chromium",
+    "nameRu": "Хром",
+    "atomicNumber": 24,
+    "atomicMass": 51.996,
+    "electronegativity": 1.66,
+    "category": "transition-metal",
+    "state": "solid",
+    "color": "#8a99c7",
+    "description": "Hardest pure metal. Chrome plating resists corrosion. Stainless steel contains 10-20% chromium.",
+    "descriptionRu": "Самый твёрдый чистый металл. Хромирование защищает от коррозии. Нержавеющая сталь содержит 10-20% хрома."
+  },
+  {
+    "symbol": "Mn",
+    "name": "Manganese",
+    "nameRu": "Марганец",
+    "atomicNumber": 25,
+    "atomicMass": 54.938,
+    "electronegativity": 1.55,
+    "category": "transition-metal",
+    "state": "solid",
+    "color": "#9c7ac7",
+    "description": "Essential for steel production. MnO₂ is a natural catalyst and battery material. Biological enzyme cofactor.",
+    "descriptionRu": "Необходим для производства стали. MnO₂ — природный катализатор и материал батарей. Кофактор биологических ферментов."
+  },
   {
     "symbol": "Fe",
     "name": "Iron",
@@ -194,6 +298,32 @@
     "description": "Strong, abundant metal. Rusts in moist air. Core of Earth is mostly iron. Magnetic.",
     "descriptionRu": "Прочный, распространённый металл. Ржавеет на влажном воздухе. Ядро Земли в основном из железа. Магнитен."
   },
+  {
+    "symbol": "Co",
+    "name": "Cobalt",
+    "nameRu": "Кобальт",
+    "atomicNumber": 27,
+    "atomicMass": 58.933,
+    "electronegativity": 1.88,
+    "category": "transition-metal",
+    "state": "solid",
+    "color": "#f090a0",
+    "description": "Source of brilliant blue pigment since antiquity. Magnetic. Essential in vitamin B12.",
+    "descriptionRu": "Источник насыщенного синего пигмента с древности. Магнитен. Входит в состав витамина B12."
+  },
+  {
+    "symbol": "Ni",
+    "name": "Nickel",
+    "nameRu": "Никель",
+    "atomicNumber": 28,
+    "atomicMass": 58.693,
+    "electronegativity": 1.91,
+    "category": "transition-metal",
+    "state": "solid",
+    "color": "#50d050",
+    "description": "Corrosion-resistant metal. Key alloy component. Excellent catalyst for hydrogenation reactions.",
+    "descriptionRu": "Коррозионностойкий металл. Важный компонент сплавов. Превосходный катализатор гидрирования."
+  },
   {
     "symbol": "Cu",
     "name": "Copper",
@@ -220,6 +350,45 @@
     "description": "Protects iron from rusting (galvanization). Zinc sulfide glows under UV light. Essential trace nutrient.",
     "descriptionRu": "Защищает железо от ржавчины (гальванизация). Сульфид цинка светится в УФ-свете. Необходимый микроэлемент."
   },
+  {
+    "symbol": "As",
+    "name": "Arsenic",
+    "nameRu": "Мышьяк",
+    "atomicNumber": 33,
+    "atomicMass": 74.922,
+    "electronegativity": 2.18,
+    "category": "metalloid",
+    "state": "solid",
+    "color": "#bd80e3",
+    "description": "Infamous poison. 'Inheritance powder' of the Borgias. Also a semiconductor used in LEDs and lasers.",
+    "descriptionRu": "Печально известный яд. «Порошок наследников» Борджиа. Также полупроводник для светодиодов и лазеров."
+  },
+  {
+    "symbol": "Br",
+    "name": "Bromine",
+    "nameRu": "Бром",
+    "atomicNumber": 35,
+    "atomicMass": 79.904,
+    "electronegativity": 2.96,
+    "category": "halogen",
+    "state": "liquid",
+    "color": "#a62929",
+    "description": "Only non-metallic element that is liquid at room temperature. Dark red, fuming, and corrosive.",
+    "descriptionRu": "Единственный неметалл, жидкий при комнатной температуре. Тёмно-красный, дымящий, едкий."
+  },
+  {
+    "symbol": "Ag",
+    "name": "Silver",
+    "nameRu": "Серебро",
+    "atomicNumber": 47,
+    "atomicMass": 107.868,
+    "electronegativity": 1.93,
+    "category": "transition-metal",
+    "state": "solid",
+    "color": "#c0c0c0",
+    "description": "Best electrical and thermal conductor of all metals. Natural antimicrobial. Tarnishes in sulfur-containing air.",
+    "descriptionRu": "Лучший проводник электричества и тепла среди металлов. Природный антисептик. Темнеет в воздухе с серой."
+  },
   {
     "symbol": "Sn",
     "name": "Tin",
@@ -233,6 +402,58 @@
     "description": "Soft, malleable metal. Resists corrosion. Used for solder and tin plating. Alloy with copper makes bronze.",
     "descriptionRu": "Мягкий, ковкий металл. Устойчив к коррозии. Используется для пайки и лужения. Сплав с медью — бронза."
   },
+  {
+    "symbol": "I",
+    "name": "Iodine",
+    "nameRu": "Йод",
+    "atomicNumber": 53,
+    "atomicMass": 126.904,
+    "electronegativity": 2.66,
+    "category": "halogen",
+    "state": "solid",
+    "color": "#940094",
+    "description": "Purple-black crystals that sublimate into violet vapor. Essential for thyroid function. Powerful disinfectant.",
+    "descriptionRu": "Пурпурно-чёрные кристаллы, сублимирующие в фиолетовый пар. Необходим для щитовидной железы. Мощный антисептик."
+  },
+  {
+    "symbol": "Ba",
+    "name": "Barium",
+    "nameRu": "Барий",
+    "atomicNumber": 56,
+    "atomicMass": 137.327,
+    "electronegativity": 0.89,
+    "category": "alkaline-earth",
+    "state": "solid",
+    "color": "#00c900",
+    "description": "Alkaline earth metal. Burns with bright green flame (fireworks!). BaSO₄ used in X-ray contrast imaging.",
+    "descriptionRu": "Щёлочноземельный металл. Горит ярко-зелёным пламенем (фейерверки!). BaSO₄ используется при рентгеновской диагностике."
+  },
+  {
+    "symbol": "W",
+    "name": "Tungsten",
+    "nameRu": "Вольфрам",
+    "atomicNumber": 74,
+    "atomicMass": 183.84,
+    "electronegativity": 2.36,
+    "category": "transition-metal",
+    "state": "solid",
+    "color": "#2194d6",
+    "description": "Highest melting point of any element (3422°C). Extremely hard and dense. Light bulb filaments.",
+    "descriptionRu": "Самая высокая температура плавления среди элементов (3422°C). Крайне твёрд и плотен. Нити накаливания ламп."
+  },
+  {
+    "symbol": "Pt",
+    "name": "Platinum",
+    "nameRu": "Платина",
+    "atomicNumber": 78,
+    "atomicMass": 195.084,
+    "electronegativity": 2.28,
+    "category": "transition-metal",
+    "state": "solid",
+    "color": "#d0d0e0",
+    "description": "Noble metal and supreme catalyst. Resists corrosion. Catalytic converters, lab equipment, jewelry.",
+    "descriptionRu": "Благородный металл и превосходный катализатор. Не поддаётся коррозии. Каталитические нейтрализаторы, лаборатории, ювелирные изделия."
+  },
   {
     "symbol": "Au",
     "name": "Gold",
@@ -258,5 +479,44 @@
     "color": "#b8b8d0",
     "description": "Only metal that is liquid at room temperature. Extremely toxic — damages brain and kidneys. Handle with extreme care.",
     "descriptionRu": "Единственный металл, жидкий при комнатной температуре. Крайне токсичен — поражает мозг и почки. Обращаться с предельной осторожностью."
+  },
+  {
+    "symbol": "Pb",
+    "name": "Lead",
+    "nameRu": "Свинец",
+    "atomicNumber": 82,
+    "atomicMass": 207.2,
+    "electronegativity": 2.33,
+    "category": "post-transition-metal",
+    "state": "solid",
+    "color": "#575961",
+    "description": "Dense, soft, toxic metal. Shields against radiation. Used in batteries. Cumulative neurotoxin.",
+    "descriptionRu": "Плотный, мягкий, токсичный металл. Экранирует от радиации. Используется в аккумуляторах. Кумулятивный нейротоксин."
+  },
+  {
+    "symbol": "Bi",
+    "name": "Bismuth",
+    "nameRu": "Висмут",
+    "atomicNumber": 83,
+    "atomicMass": 208.980,
+    "electronegativity": 2.02,
+    "category": "post-transition-metal",
+    "state": "solid",
+    "color": "#9e4fb5",
+    "description": "Least toxic heavy metal. Forms beautiful iridescent crystals. Used in Pepto-Bismol and cosmetics.",
+    "descriptionRu": "Наименее токсичный тяжёлый металл. Образует красивые радужные кристаллы. Применяется в медицине и косметике."
+  },
+  {
+    "symbol": "U",
+    "name": "Uranium",
+    "nameRu": "Уран",
+    "atomicNumber": 92,
+    "atomicMass": 238.029,
+    "electronegativity": 1.38,
+    "category": "actinide",
+    "state": "solid",
+    "color": "#008fff",
+    "description": "Radioactive element. Enormous energy density — 1 kg equals 3000 tonnes of coal. Powers nuclear reactors.",
+    "descriptionRu": "Радиоактивный элемент. Колоссальная плотность энергии — 1 кг равен 3000 тоннам угля. Питает ядерные реакторы."
   }
 ]

src/data/mycelium.json

@@ -0,0 +1,75 @@
+{
+  "sporeBonuses": [
+    {
+      "id": "vitality",
+      "name": "Vital Spores",
+      "nameRu": "Споры Живучести",
+      "description": "Mycelium reinforces your body. +25 max health.",
+      "descriptionRu": "Мицелий укрепляет тело. +25 к максимальному здоровью.",
+      "cost": 20,
+      "effect": { "type": "extra_health", "amount": 25 },
+      "repeatable": true
+    },
+    {
+      "id": "carbon_gift",
+      "name": "Carbon Cache",
+      "nameRu": "Запас Углерода",
+      "description": "A fungal node releases stored carbon. +3 C.",
+      "descriptionRu": "Грибной узел отдаёт накопленный углерод. +3 C.",
+      "cost": 10,
+      "effect": { "type": "extra_element", "symbol": "C", "quantity": 3 },
+      "repeatable": true
+    },
+    {
+      "id": "sulfur_gift",
+      "name": "Sulfur Reserve",
+      "nameRu": "Запас Серы",
+      "description": "Deep mycelium threads carry sulfur to the surface. +3 S.",
+      "descriptionRu": "Глубинные нити мицелия доставляют серу. +3 S.",
+      "cost": 10,
+      "effect": { "type": "extra_element", "symbol": "S", "quantity": 3 },
+      "repeatable": true
+    },
+    {
+      "id": "iron_gift",
+      "name": "Iron Vein",
+      "nameRu": "Железная Жила",
+      "description": "The network has absorbed iron from old ruins. +2 Fe.",
+      "descriptionRu": "Сеть впитала железо из древних руин. +2 Fe.",
+      "cost": 15,
+      "effect": { "type": "extra_element", "symbol": "Fe", "quantity": 2 },
+      "repeatable": true
+    },
+    {
+      "id": "memory_boost",
+      "name": "Fungal Attunement",
+      "nameRu": "Грибная Настройка",
+      "description": "Clearer memories from the network. Memory flashes are more detailed.",
+      "descriptionRu": "Яснее воспоминания сети. Вспышки памяти более детальны.",
+      "cost": 30,
+      "effect": { "type": "knowledge_boost", "multiplier": 1.5 },
+      "repeatable": false
+    }
+  ],
+  "memoryTemplates": {
+    "element_hint": [
+      { "text": "A faint echo... {element} reacts with something nearby...", "textRu": "Слабое эхо... {element} реагирует с чем-то рядом..." },
+      { "text": "The network remembers: {element} was useful here...", "textRu": "Сеть помнит: {element} был полезен здесь..." },
+      { "text": "Traces of {element} flow through the mycelium threads...", "textRu": "Следы {element} текут по нитям мицелия..." }
+    ],
+    "reaction_hint": [
+      { "text": "A past adept combined... the result was {compound}...", "textRu": "Прошлый адепт комбинировал... результат — {compound}..." },
+      { "text": "The fungal memory shows: mixing yields {compound}...", "textRu": "Грибная память показывает: смешение даёт {compound}..." },
+      { "text": "Chemical echoes: a reaction produced {compound} here...", "textRu": "Химическое эхо: реакция создала {compound} здесь..." }
+    ],
+    "creature_hint": [
+      { "text": "Beware: {creature} was observed in this region...", "textRu": "Осторожно: {creature} замечен в этом регионе..." },
+      { "text": "The network felt vibrations... {creature} territory...", "textRu": "Сеть ощутила вибрации... территория {creature}..." }
+    ],
+    "lore": [
+      { "text": "...the cycle continues. What dies feeds what grows...", "textRu": "...цикл продолжается. Что умирает, питает растущее..." },
+      { "text": "...synthesis is not creation. It is transformation...", "textRu": "...синтез — не создание. Это трансформация..." },
+      { "text": "...the Mycelium remembers all who walked these paths...", "textRu": "...Мицелий помнит всех, кто шёл этими тропами..." }
+    ]
+  }
+}

src/data/reactions.json

@@ -322,5 +322,822 @@
     "description": "Lime burning: heating limestone drives off CO₂, leaving quicklime. Ancient building technology.",
     "descriptionRu": "Обжиг извести: нагрев известняка выгоняет CO₂, оставляя негашёную известь. Древняя строительная технология.",
     "difficulty": 3
+  },
+
+  {
+    "id": "synth_hf", "type": "synthesis",
+    "reactants": [{ "id": "H", "count": 1 }, { "id": "F", "count": 1 }],
+    "products": [{ "id": "HF", "count": 1 }],
+    "energyChange": -3,
+    "description": "Hydrogen + fluorine combine to form hydrofluoric acid — dissolves glass!",
+    "descriptionRu": "Водород + фтор образуют плавиковую кислоту — растворяет стекло!",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_hbr", "type": "synthesis",
+    "reactants": [{ "id": "H", "count": 1 }, { "id": "Br", "count": 1 }],
+    "products": [{ "id": "HBr", "count": 1 }],
+    "energyChange": -4,
+    "description": "Hydrogen + bromine → hydrobromic acid, a strong acid",
+    "descriptionRu": "Водород + бром → бромоводородная кислота, сильная кислота",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_hi", "type": "synthesis",
+    "reactants": [{ "id": "H", "count": 1 }, { "id": "I", "count": 1 }],
+    "products": [{ "id": "HI", "count": 1 }],
+    "energyChange": -3,
+    "description": "Hydrogen + iodine → hydroiodic acid. Strongest hydrohalic acid",
+    "descriptionRu": "Водород + йод → йодоводородная кислота. Самая сильная галогенводородная кислота",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_licl", "type": "synthesis",
+    "reactants": [{ "id": "Li", "count": 1 }, { "id": "Cl", "count": 1 }],
+    "products": [{ "id": "LiCl", "count": 1 }],
+    "energyChange": -38,
+    "description": "Lithium + chlorine → lithium chloride. Hygroscopic desiccant",
+    "descriptionRu": "Литий + хлор → хлорид лития. Гигроскопичный осушитель",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_lioh", "type": "synthesis",
+    "reactants": [{ "id": "Li", "count": 1 }, { "id": "O", "count": 1 }, { "id": "H", "count": 1 }],
+    "products": [{ "id": "LiOH", "count": 1 }],
+    "energyChange": -45,
+    "description": "Lithium hydroxide synthesis. Used in spacecraft CO₂ scrubbers",
+    "descriptionRu": "Синтез гидроксида лития. Используется для очистки воздуха на космических кораблях",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_agcl", "type": "synthesis",
+    "reactants": [{ "id": "Ag", "count": 1 }, { "id": "Cl", "count": 1 }],
+    "products": [{ "id": "AgCl", "count": 1 }],
+    "energyChange": -13,
+    "description": "Silver + chlorine → silver chloride. Darkens in light — basis of photography",
+    "descriptionRu": "Серебро + хлор → хлорид серебра. Темнеет на свету — основа фотографии",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_agbr", "type": "synthesis",
+    "reactants": [{ "id": "Ag", "count": 1 }, { "id": "Br", "count": 1 }],
+    "products": [{ "id": "AgBr", "count": 1 }],
+    "energyChange": -10,
+    "description": "Silver + bromine → silver bromide. More light-sensitive than AgCl",
+    "descriptionRu": "Серебро + бром → бромид серебра. Светочувствительнее AgCl",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_pbs", "type": "synthesis",
+    "reactants": [{ "id": "Pb", "count": 1 }, { "id": "S", "count": 1 }],
+    "products": [{ "id": "PbS", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -10,
+    "description": "Lead + sulfur → galena (lead sulfide). First semiconductor",
+    "descriptionRu": "Свинец + сера → галенит (сульфид свинца). Первый полупроводник",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_nicl2", "type": "synthesis",
+    "reactants": [{ "id": "Ni", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "products": [{ "id": "NiCl2", "count": 1 }],
+    "energyChange": -31,
+    "description": "Nickel + chlorine → green nickel chloride. Electroplating reagent",
+    "descriptionRu": "Никель + хлор → зелёный хлорид никеля. Реагент для гальваники",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_naf", "type": "synthesis",
+    "reactants": [{ "id": "Na", "count": 1 }, { "id": "F", "count": 1 }],
+    "products": [{ "id": "NaF", "count": 1 }],
+    "energyChange": -57,
+    "description": "Sodium + fluorine → sodium fluoride. Active ingredient in toothpaste",
+    "descriptionRu": "Натрий + фтор → фторид натрия. Активный компонент зубной пасты",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_nabr", "type": "synthesis",
+    "reactants": [{ "id": "Na", "count": 1 }, { "id": "Br", "count": 1 }],
+    "products": [{ "id": "NaBr", "count": 1 }],
+    "energyChange": -36,
+    "description": "Sodium + bromine → sodium bromide. Historical sedative",
+    "descriptionRu": "Натрий + бром → бромид натрия. Историческое седативное средство",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_kf", "type": "synthesis",
+    "reactants": [{ "id": "K", "count": 1 }, { "id": "F", "count": 1 }],
+    "products": [{ "id": "KF", "count": 1 }],
+    "energyChange": -56,
+    "description": "Potassium + fluorine → potassium fluoride",
+    "descriptionRu": "Калий + фтор → фторид калия",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_kbr", "type": "synthesis",
+    "reactants": [{ "id": "K", "count": 1 }, { "id": "Br", "count": 1 }],
+    "products": [{ "id": "KBr", "count": 1 }],
+    "energyChange": -39,
+    "description": "Potassium + bromine → potassium bromide. Photography essential",
+    "descriptionRu": "Калий + бром → бромид калия. Незаменим в фотографии",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_mgcl2", "type": "synthesis",
+    "reactants": [{ "id": "Mg", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "products": [{ "id": "MgCl2", "count": 1 }],
+    "energyChange": -64,
+    "description": "Magnesium + chlorine → magnesium chloride. De-icing salt",
+    "descriptionRu": "Магний + хлор → хлорид магния. Противогололёдная соль",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_cacl2", "type": "synthesis",
+    "reactants": [{ "id": "Ca", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "products": [{ "id": "CaCl2", "count": 1 }],
+    "energyChange": -80,
+    "description": "Calcium + chlorine → calcium chloride. Powerful desiccant",
+    "descriptionRu": "Кальций + хлор → хлорид кальция. Мощный осушитель",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_bacl2", "type": "synthesis",
+    "reactants": [{ "id": "Ba", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "products": [{ "id": "BaCl2", "count": 1 }],
+    "energyChange": -86,
+    "description": "Barium + chlorine → barium chloride. Green flame reagent",
+    "descriptionRu": "Барий + хлор → хлорид бария. Реагент зелёного пламени",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_fecl3", "type": "synthesis",
+    "reactants": [{ "id": "Fe", "count": 1 }, { "id": "Cl", "count": 3 }],
+    "products": [{ "id": "FeCl3", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -40,
+    "description": "Iron + excess chlorine → iron(III) chloride. Etches copper circuit boards",
+    "descriptionRu": "Железо + избыток хлора → хлорид железа(III). Травит медные платы",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_fecl2", "type": "synthesis",
+    "reactants": [{ "id": "Fe", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "products": [{ "id": "FeCl2", "count": 1 }],
+    "energyChange": -34,
+    "description": "Iron + chlorine → iron(II) chloride. Reducing agent",
+    "descriptionRu": "Железо + хлор → хлорид железа(II). Восстановитель",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_cucl2", "type": "synthesis",
+    "reactants": [{ "id": "Cu", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "products": [{ "id": "CuCl2", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -22,
+    "description": "Copper + chlorine at heat → green copper(II) chloride crystals",
+    "descriptionRu": "Медь + хлор при нагреве → зелёные кристаллы хлорида меди(II)",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_zncl2", "type": "synthesis",
+    "reactants": [{ "id": "Zn", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "products": [{ "id": "ZnCl2", "count": 1 }],
+    "energyChange": -42,
+    "description": "Zinc + chlorine → zinc chloride. Soldering flux",
+    "descriptionRu": "Цинк + хлор → хлорид цинка. Паяльный флюс",
+    "difficulty": 1
+  },
+  {
+    "id": "synth_na2o", "type": "synthesis",
+    "reactants": [{ "id": "Na", "count": 2 }, { "id": "O", "count": 1 }],
+    "products": [{ "id": "Na2O", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -42,
+    "description": "Sodium burns in limited oxygen → sodium oxide. Key to glass making",
+    "descriptionRu": "Натрий горит в ограниченном кислороде → оксид натрия. Ключ к стекловарению",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_nh3", "type": "synthesis",
+    "reactants": [{ "id": "N", "count": 1 }, { "id": "H", "count": 3 }],
+    "products": [{ "id": "NH3", "count": 1 }],
+    "conditions": { "minTemp": 500, "catalyst": "Fe" },
+    "energyChange": -5,
+    "description": "Haber process: nitrogen + hydrogen with iron catalyst → ammonia. Nobel Prize reaction",
+    "descriptionRu": "Процесс Габера: азот + водород с железным катализатором → аммиак. Нобелевская реакция",
+    "difficulty": 3
+  },
+  {
+    "id": "synth_h2s", "type": "synthesis",
+    "reactants": [{ "id": "H", "count": 2 }, { "id": "S", "count": 1 }],
+    "products": [{ "id": "H2S", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -2,
+    "description": "Hydrogen + sulfur → hydrogen sulfide. Rotten egg gas",
+    "descriptionRu": "Водород + сера → сероводород. Газ с запахом тухлых яиц",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_h2so4", "type": "synthesis",
+    "reactants": [{ "id": "S", "count": 1 }, { "id": "O", "count": 3 }, { "id": "H", "count": 2 }],
+    "products": [{ "id": "H2SO4", "count": 1 }],
+    "conditions": { "catalyst": "Pt" },
+    "energyChange": -14,
+    "description": "Contact process: sulfur, oxygen, hydrogen with platinum catalyst → sulfuric acid",
+    "descriptionRu": "Контактный процесс: сера, кислород, водород с платиновым катализатором → серная кислота",
+    "difficulty": 4
+  },
+  {
+    "id": "synth_hno3", "type": "synthesis",
+    "reactants": [{ "id": "N", "count": 1 }, { "id": "O", "count": 3 }, { "id": "H", "count": 1 }],
+    "products": [{ "id": "HNO3", "count": 1 }],
+    "conditions": { "catalyst": "Pt" },
+    "energyChange": -5,
+    "description": "Ostwald process: nitrogen, oxygen, hydrogen with platinum catalyst → nitric acid",
+    "descriptionRu": "Процесс Оствальда: азот, кислород, водород с платиновым катализатором → азотная кислота",
+    "difficulty": 4
+  },
+  {
+    "id": "synth_nh4cl", "type": "synthesis",
+    "reactants": [{ "id": "NH3", "count": 1 }, { "id": "HCl", "count": 1 }],
+    "products": [{ "id": "NH4Cl", "count": 1 }],
+    "energyChange": -18,
+    "description": "Ammonia + HCl → white smoke of ammonium chloride! Classic demonstration",
+    "descriptionRu": "Аммиак + HCl → белый дым хлорида аммония! Классическая демонстрация",
+    "difficulty": 2
+  },
+  {
+    "id": "synth_ch3cooh", "type": "synthesis",
+    "reactants": [{ "id": "C", "count": 2 }, { "id": "H", "count": 4 }, { "id": "O", "count": 2 }],
+    "products": [{ "id": "CH3COOH", "count": 1 }],
+    "conditions": { "catalyst": "Cu" },
+    "energyChange": -5,
+    "description": "Acetic acid synthesis with copper catalyst. The chemistry of vinegar",
+    "descriptionRu": "Синтез уксусной кислоты с медным катализатором. Химия уксуса",
+    "difficulty": 4
+  },
+  {
+    "id": "synth_c6h12o6", "type": "synthesis",
+    "reactants": [{ "id": "C", "count": 6 }, { "id": "H", "count": 12 }, { "id": "O", "count": 6 }],
+    "products": [{ "id": "C6H12O6", "count": 1 }],
+    "conditions": { "requiresEnergy": true },
+    "energyChange": 28,
+    "description": "Artificial photosynthesis: assembling glucose from its elements. Requires enormous energy",
+    "descriptionRu": "Искусственный фотосинтез: сборка глюкозы из элементов. Требует огромной энергии",
+    "difficulty": 5
+  },
+
+  {
+    "id": "comb_tio2", "type": "combustion",
+    "reactants": [{ "id": "Ti", "count": 1 }, { "id": "O", "count": 2 }],
+    "products": [{ "id": "TiO2", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -94,
+    "description": "Titanium burns brilliantly in pure oxygen. Produces white titanium dioxide",
+    "descriptionRu": "Титан ярко горит в чистом кислороде. Образует белый диоксид титана",
+    "difficulty": 4
+  },
+  {
+    "id": "comb_cr2o3", "type": "combustion",
+    "reactants": [{ "id": "Cr", "count": 2 }, { "id": "O", "count": 3 }],
+    "products": [{ "id": "Cr2O3", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -113,
+    "description": "Chromium oxidation at extreme heat → green chromium oxide. Hard as corundum",
+    "descriptionRu": "Окисление хрома при экстремальном нагреве → зелёный оксид хрома. Твёрд как корунд",
+    "difficulty": 4
+  },
+  {
+    "id": "comb_mno2", "type": "combustion",
+    "reactants": [{ "id": "Mn", "count": 1 }, { "id": "O", "count": 2 }],
+    "products": [{ "id": "MnO2", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -52,
+    "description": "Manganese + oxygen → manganese dioxide. Nature's battery material and catalyst",
+    "descriptionRu": "Марганец + кислород → диоксид марганца. Природный материал батарей и катализатор",
+    "difficulty": 3
+  },
+  {
+    "id": "comb_coo", "type": "combustion",
+    "reactants": [{ "id": "Co", "count": 1 }, { "id": "O", "count": 1 }],
+    "products": [{ "id": "CoO", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -24,
+    "description": "Cobalt burns to form cobalt oxide — brilliant blue ceramic pigment",
+    "descriptionRu": "Кобальт горит, образуя оксид кобальта — великолепный синий керамический пигмент",
+    "difficulty": 2
+  },
+  {
+    "id": "comb_cuo", "type": "combustion",
+    "reactants": [{ "id": "Cu", "count": 1 }, { "id": "O", "count": 1 }],
+    "products": [{ "id": "CuO", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -16,
+    "description": "Copper oxidation → black copper(II) oxide. Basis of ancient smelting",
+    "descriptionRu": "Окисление меди → чёрный оксид меди(II). Основа древней металлургии",
+    "difficulty": 2
+  },
+  {
+    "id": "comb_bao", "type": "combustion",
+    "reactants": [{ "id": "Ba", "count": 1 }, { "id": "O", "count": 1 }],
+    "products": [{ "id": "BaO", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -56,
+    "description": "Barium burns with brilliant GREEN flame → barium oxide",
+    "descriptionRu": "Барий горит ярко-ЗЕЛЁНЫМ пламенем → оксид бария",
+    "difficulty": 2
+  },
+  {
+    "id": "comb_wo3", "type": "combustion",
+    "reactants": [{ "id": "W", "count": 1 }, { "id": "O", "count": 3 }],
+    "products": [{ "id": "WO3", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -84,
+    "description": "Tungsten slowly oxidizes only at extreme temperatures. Highest melting point element",
+    "descriptionRu": "Вольфрам окисляется лишь при экстремальных температурах. Элемент с наивысшей температурой плавления",
+    "difficulty": 5
+  },
+  {
+    "id": "comb_pbo", "type": "combustion",
+    "reactants": [{ "id": "Pb", "count": 1 }, { "id": "O", "count": 1 }],
+    "products": [{ "id": "PbO", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -22,
+    "description": "Lead oxidation → litharge (yellow lead oxide). Battery material",
+    "descriptionRu": "Окисление свинца → глёт (жёлтый оксид свинца). Материал аккумуляторов",
+    "difficulty": 2
+  },
+  {
+    "id": "comb_bi2o3", "type": "combustion",
+    "reactants": [{ "id": "Bi", "count": 2 }, { "id": "O", "count": 3 }],
+    "products": [{ "id": "Bi2O3", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -58,
+    "description": "Bismuth burns → bismuth trioxide. Medicinal compound",
+    "descriptionRu": "Висмут горит → оксид висмута(III). Лекарственное соединение",
+    "difficulty": 3
+  },
+  {
+    "id": "comb_uo2", "type": "combustion",
+    "reactants": [{ "id": "U", "count": 1 }, { "id": "O", "count": 2 }],
+    "products": [{ "id": "UO2", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -109,
+    "description": "Uranium oxidation → uranium dioxide. Nuclear fuel pellets",
+    "descriptionRu": "Окисление урана → диоксид урана. Таблетки ядерного топлива",
+    "difficulty": 5
+  },
+  {
+    "id": "comb_as2o3", "type": "combustion",
+    "reactants": [{ "id": "As", "count": 2 }, { "id": "O", "count": 3 }],
+    "products": [{ "id": "As2O3", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -66,
+    "description": "Arsenic combustion → arsenic trioxide. The 'King of Poisons'",
+    "descriptionRu": "Горение мышьяка → оксид мышьяка(III). «Король ядов»",
+    "difficulty": 3
+  },
+  {
+    "id": "comb_ch4", "type": "combustion",
+    "reactants": [{ "id": "CH4", "count": 1 }, { "id": "O", "count": 4 }],
+    "products": [{ "id": "CO2", "count": 1 }, { "id": "H2O", "count": 2 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -89,
+    "description": "Methane combustion: natural gas burning. Clean energy source",
+    "descriptionRu": "Горение метана: сжигание природного газа. Чистый источник энергии",
+    "difficulty": 2
+  },
+  {
+    "id": "comb_c2h5oh", "type": "combustion",
+    "reactants": [{ "id": "C2H5OH", "count": 1 }, { "id": "O", "count": 6 }],
+    "products": [{ "id": "CO2", "count": 2 }, { "id": "H2O", "count": 3 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -137,
+    "description": "Ethanol burns with blue flame. Clean-burning biofuel",
+    "descriptionRu": "Этанол горит синим пламенем. Чистое биотопливо",
+    "difficulty": 3
+  },
+  {
+    "id": "comb_h2s", "type": "combustion",
+    "reactants": [{ "id": "H2S", "count": 1 }, { "id": "O", "count": 3 }],
+    "products": [{ "id": "SO2", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -52,
+    "description": "Hydrogen sulfide burns → sulfur dioxide + water. Converting one toxic gas to another",
+    "descriptionRu": "Сероводород горит → сернистый газ + вода. Превращение одного токсичного газа в другой",
+    "difficulty": 2
+  },
+  {
+    "id": "comb_co_full", "type": "combustion",
+    "reactants": [{ "id": "CO", "count": 1 }, { "id": "O", "count": 1 }],
+    "products": [{ "id": "CO2", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -28,
+    "description": "Carbon monoxide burns to carbon dioxide. Converting deadly poison to harmless gas",
+    "descriptionRu": "Угарный газ горит до углекислого. Превращение смертельного яда в безвредный газ",
+    "difficulty": 1
+  },
+  {
+    "id": "comb_glucose", "type": "combustion",
+    "reactants": [{ "id": "C6H12O6", "count": 1 }, { "id": "O", "count": 12 }],
+    "products": [{ "id": "CO2", "count": 6 }, { "id": "H2O", "count": 6 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -280,
+    "description": "Glucose combustion — same as cellular respiration. Maximum energy release from sugar",
+    "descriptionRu": "Горение глюкозы — то же, что клеточное дыхание. Максимальное выделение энергии из сахара",
+    "difficulty": 3
+  },
+
+  {
+    "id": "repl_li_h2o", "type": "single-replacement",
+    "reactants": [{ "id": "Li", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "products": [{ "id": "LiOH", "count": 1 }, { "id": "H", "count": 1 }],
+    "energyChange": -50,
+    "description": "Lithium fizzes gently in water → lithium hydroxide + hydrogen. Less violent than sodium",
+    "descriptionRu": "Литий тихо шипит в воде → гидроксид лития + водород. Менее бурно, чем натрий",
+    "difficulty": 1
+  },
+  {
+    "id": "repl_mg_hcl", "type": "single-replacement",
+    "reactants": [{ "id": "Mg", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "MgCl2", "count": 1 }, { "id": "H", "count": 2 }],
+    "energyChange": -46,
+    "description": "Magnesium dissolves in acid with vigorous hydrogen bubbling",
+    "descriptionRu": "Магний растворяется в кислоте с бурным выделением пузырьков водорода",
+    "difficulty": 2
+  },
+  {
+    "id": "repl_zn_hcl", "type": "single-replacement",
+    "reactants": [{ "id": "Zn", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "ZnCl2", "count": 1 }, { "id": "H", "count": 2 }],
+    "energyChange": -15,
+    "description": "Zinc dissolves in hydrochloric acid → zinc chloride + hydrogen gas",
+    "descriptionRu": "Цинк растворяется в соляной кислоте → хлорид цинка + водород",
+    "difficulty": 2
+  },
+  {
+    "id": "repl_fe_hcl", "type": "single-replacement",
+    "reactants": [{ "id": "Fe", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "FeCl2", "count": 1 }, { "id": "H", "count": 2 }],
+    "energyChange": -9,
+    "description": "Iron dissolves in acid → pale green iron(II) chloride + hydrogen",
+    "descriptionRu": "Железо растворяется в кислоте → бледно-зелёный хлорид железа(II) + водород",
+    "difficulty": 2
+  },
+  {
+    "id": "repl_ni_hcl", "type": "single-replacement",
+    "reactants": [{ "id": "Ni", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "NiCl2", "count": 1 }, { "id": "H", "count": 2 }],
+    "energyChange": -8,
+    "description": "Nickel dissolves slowly in HCl → green nickel chloride solution",
+    "descriptionRu": "Никель медленно растворяется в HCl → зелёный раствор хлорида никеля",
+    "difficulty": 2
+  },
+  {
+    "id": "repl_fe_cucl2", "type": "single-replacement",
+    "reactants": [{ "id": "Fe", "count": 1 }, { "id": "CuCl2", "count": 1 }],
+    "products": [{ "id": "FeCl2", "count": 1 }, { "id": "Cu", "count": 1 }],
+    "energyChange": -15,
+    "description": "Iron displaces copper from solution. Activity series: Fe > Cu",
+    "descriptionRu": "Железо вытесняет медь из раствора. Ряд активности: Fe > Cu",
+    "difficulty": 2
+  },
+  {
+    "id": "repl_zn_cucl2", "type": "single-replacement",
+    "reactants": [{ "id": "Zn", "count": 1 }, { "id": "CuCl2", "count": 1 }],
+    "products": [{ "id": "ZnCl2", "count": 1 }, { "id": "Cu", "count": 1 }],
+    "energyChange": -22,
+    "description": "Zinc displaces copper — red copper deposits on zinc surface",
+    "descriptionRu": "Цинк вытесняет медь — красная медь осаждается на поверхности цинка",
+    "difficulty": 2
+  },
+  {
+    "id": "repl_zn_fecl2", "type": "single-replacement",
+    "reactants": [{ "id": "Zn", "count": 1 }, { "id": "FeCl2", "count": 1 }],
+    "products": [{ "id": "ZnCl2", "count": 1 }, { "id": "Fe", "count": 1 }],
+    "energyChange": -7,
+    "description": "Zinc displaces iron from solution. Zinc is more reactive",
+    "descriptionRu": "Цинк вытесняет железо из раствора. Цинк активнее",
+    "difficulty": 2
+  },
+  {
+    "id": "repl_mg_cucl2", "type": "single-replacement",
+    "reactants": [{ "id": "Mg", "count": 1 }, { "id": "CuCl2", "count": 1 }],
+    "products": [{ "id": "MgCl2", "count": 1 }, { "id": "Cu", "count": 1 }],
+    "energyChange": -60,
+    "description": "Magnesium violently displaces copper. Extreme activity difference",
+    "descriptionRu": "Магний бурно вытесняет медь. Огромная разница активности",
+    "difficulty": 1
+  },
+
+  {
+    "id": "ab_lioh_hcl", "type": "acid-base",
+    "reactants": [{ "id": "LiOH", "count": 1 }, { "id": "HCl", "count": 1 }],
+    "products": [{ "id": "LiCl", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -55,
+    "description": "Neutralization: lithium hydroxide + hydrochloric acid → lithium chloride + water",
+    "descriptionRu": "Нейтрализация: гидроксид лития + соляная кислота → хлорид лития + вода",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_naoh_hf", "type": "acid-base",
+    "reactants": [{ "id": "NaOH", "count": 1 }, { "id": "HF", "count": 1 }],
+    "products": [{ "id": "NaF", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -68,
+    "description": "Neutralizing deadly HF with lye → safe sodium fluoride + water",
+    "descriptionRu": "Нейтрализация опасного HF щёлочью → безопасный фторид натрия + вода",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_naoh_hbr", "type": "acid-base",
+    "reactants": [{ "id": "NaOH", "count": 1 }, { "id": "HBr", "count": 1 }],
+    "products": [{ "id": "NaBr", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -56,
+    "description": "Neutralization: NaOH + HBr → sodium bromide + water",
+    "descriptionRu": "Нейтрализация: NaOH + HBr → бромид натрия + вода",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_koh_hf", "type": "acid-base",
+    "reactants": [{ "id": "KOH", "count": 1 }, { "id": "HF", "count": 1 }],
+    "products": [{ "id": "KF", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -68,
+    "description": "Potassium hydroxide neutralizes hydrofluoric acid",
+    "descriptionRu": "Гидроксид калия нейтрализует плавиковую кислоту",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_koh_hbr", "type": "acid-base",
+    "reactants": [{ "id": "KOH", "count": 1 }, { "id": "HBr", "count": 1 }],
+    "products": [{ "id": "KBr", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -56,
+    "description": "KOH + HBr → potassium bromide + water",
+    "descriptionRu": "KOH + HBr → бромид калия + вода",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_caco3_hcl", "type": "acid-base",
+    "reactants": [{ "id": "CaCO3", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "CaCl2", "count": 1 }, { "id": "H2O", "count": 1 }, { "id": "CO2", "count": 1 }],
+    "energyChange": -12,
+    "description": "Limestone + acid → fizzing! Calcium chloride + water + CO₂. The cave dissolving reaction",
+    "descriptionRu": "Известняк + кислота → шипение! Хлорид кальция + вода + CO₂. Реакция растворения пещер",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_cuo_hcl", "type": "acid-base",
+    "reactants": [{ "id": "CuO", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "CuCl2", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -13,
+    "description": "Copper oxide + acid → blue-green copper chloride solution + water",
+    "descriptionRu": "Оксид меди + кислота → сине-зелёный раствор хлорида меди + вода",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_zno_hcl", "type": "acid-base",
+    "reactants": [{ "id": "ZnO", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "ZnCl2", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -14,
+    "description": "Zinc oxide + acid → zinc chloride + water. Classic oxide-acid reaction",
+    "descriptionRu": "Оксид цинка + кислота → хлорид цинка + вода. Классическая реакция оксида с кислотой",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_mgo_hcl", "type": "acid-base",
+    "reactants": [{ "id": "MgO", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "MgCl2", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -15,
+    "description": "Antacid reaction: magnesium oxide neutralizes stomach acid",
+    "descriptionRu": "Антацидная реакция: оксид магния нейтрализует желудочную кислоту",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_bao_hcl", "type": "acid-base",
+    "reactants": [{ "id": "BaO", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "BaCl2", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -17,
+    "description": "Barium oxide + acid → toxic barium chloride. Handle carefully",
+    "descriptionRu": "Оксид бария + кислота → токсичный хлорид бария. Осторожно",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_caoh2_hcl", "type": "acid-base",
+    "reactants": [{ "id": "CaOH2", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "CaCl2", "count": 1 }, { "id": "H2O", "count": 2 }],
+    "energyChange": -58,
+    "description": "Slaked lime + acid → calcium chloride + water. Water treatment",
+    "descriptionRu": "Гашёная известь + кислота → хлорид кальция + вода. Очистка воды",
+    "difficulty": 2
+  },
+  {
+    "id": "ab_na2o_hcl", "type": "acid-base",
+    "reactants": [{ "id": "Na2O", "count": 1 }, { "id": "HCl", "count": 2 }],
+    "products": [{ "id": "NaCl", "count": 2 }, { "id": "H2O", "count": 1 }],
+    "energyChange": -60,
+    "description": "Sodium oxide + acid → table salt + water",
+    "descriptionRu": "Оксид натрия + кислота → поваренная соль + вода",
+    "difficulty": 2
+  },
+  {
+    "id": "repl_na2o_h2o", "type": "single-replacement",
+    "reactants": [{ "id": "Na2O", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "products": [{ "id": "NaOH", "count": 2 }],
+    "energyChange": -70,
+    "description": "Sodium oxide dissolves in water → caustic soda (NaOH). Exothermic!",
+    "descriptionRu": "Оксид натрия растворяется в воде → каустическая сода (NaOH). Экзотермическая!",
+    "difficulty": 1
+  },
+
+  {
+    "id": "decomp_nh3", "type": "decomposition",
+    "reactants": [{ "id": "NH3", "count": 1 }],
+    "products": [{ "id": "N", "count": 1 }, { "id": "H", "count": 3 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": 5,
+    "description": "Ammonia decomposes at extreme heat → nitrogen + hydrogen. Reversed Haber process",
+    "descriptionRu": "Аммиак разлагается при экстремальном нагреве → азот + водород. Обратный процесс Габера",
+    "difficulty": 3
+  },
+  {
+    "id": "decomp_h2s", "type": "decomposition",
+    "reactants": [{ "id": "H2S", "count": 1 }],
+    "products": [{ "id": "H", "count": 2 }, { "id": "S", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": 2,
+    "description": "Thermal decomposition of hydrogen sulfide → hydrogen + sulfur",
+    "descriptionRu": "Термическое разложение сероводорода → водород + сера",
+    "difficulty": 3
+  },
+  {
+    "id": "decomp_hno3", "type": "decomposition",
+    "reactants": [{ "id": "HNO3", "count": 1 }],
+    "products": [{ "id": "N", "count": 1 }, { "id": "O", "count": 3 }, { "id": "H", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": 5,
+    "description": "Nitric acid decomposes under heat → brown toxic fumes",
+    "descriptionRu": "Азотная кислота разлагается при нагреве → бурые токсичные пары",
+    "difficulty": 3
+  },
+  {
+    "id": "decomp_h2so4", "type": "decomposition",
+    "reactants": [{ "id": "H2SO4", "count": 1 }],
+    "products": [{ "id": "S", "count": 1 }, { "id": "O", "count": 3 }, { "id": "H", "count": 2 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": 10,
+    "description": "Sulfuric acid decomposition at extreme heat. Very endothermic",
+    "descriptionRu": "Разложение серной кислоты при экстремальном нагреве. Сильно эндотермическое",
+    "difficulty": 4
+  },
+  
+  {
+    "id": "decomp_nacl_electro", "type": "decomposition",
+    "reactants": [{ "id": "NaCl", "count": 1 }],
+    "products": [{ "id": "Na", "count": 1 }, { "id": "Cl", "count": 1 }],
+    "conditions": { "requiresEnergy": true },
+    "energyChange": 41,
+    "description": "Electrolysis of molten salt → pure sodium + chlorine gas. Industrial sodium production",
+    "descriptionRu": "Электролиз расплава соли → чистый натрий + хлор. Промышленное получение натрия",
+    "difficulty": 3
+  },
+  {
+    "id": "decomp_mgcl2", "type": "decomposition",
+    "reactants": [{ "id": "MgCl2", "count": 1 }],
+    "products": [{ "id": "Mg", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "conditions": { "requiresEnergy": true },
+    "energyChange": 64,
+    "description": "Electrolysis of molten MgCl₂ → magnesium metal + chlorine. Dow process",
+    "descriptionRu": "Электролиз расплава MgCl₂ → металлический магний + хлор. Процесс Дау",
+    "difficulty": 3
+  },
+  {
+    "id": "decomp_cacl2", "type": "decomposition",
+    "reactants": [{ "id": "CaCl2", "count": 1 }],
+    "products": [{ "id": "Ca", "count": 1 }, { "id": "Cl", "count": 2 }],
+    "conditions": { "requiresEnergy": true },
+    "energyChange": 80,
+    "description": "Electrolysis of molten CaCl₂ → pure calcium metal",
+    "descriptionRu": "Электролиз расплава CaCl₂ → чистый металлический кальций",
+    "difficulty": 3
+  },
+  {
+    "id": "decomp_al2o3", "type": "decomposition",
+    "reactants": [{ "id": "Al2O3", "count": 1 }],
+    "products": [{ "id": "Al", "count": 2 }, { "id": "O", "count": 3 }],
+    "conditions": { "requiresEnergy": true },
+    "energyChange": 84,
+    "description": "Hall-Héroult process: alumina electrolysis → aluminum. Most energy-intensive industrial process",
+    "descriptionRu": "Процесс Холла-Эру: электролиз глинозёма → алюминий. Самый энергоёмкий промышленный процесс",
+    "difficulty": 4
+  },
+  {
+    "id": "decomp_fecl3", "type": "decomposition",
+    "reactants": [{ "id": "FeCl3", "count": 1 }],
+    "products": [{ "id": "Fe", "count": 1 }, { "id": "Cl", "count": 3 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": 40,
+    "description": "Iron(III) chloride thermal decomposition → iron + chlorine gas",
+    "descriptionRu": "Термическое разложение хлорида железа(III) → железо + хлор",
+    "difficulty": 3
+  },
+
+  {
+    "id": "redox_cr2o3_al", "type": "redox",
+    "reactants": [{ "id": "Cr2O3", "count": 1 }, { "id": "Al", "count": 2 }],
+    "products": [{ "id": "Cr", "count": 2 }, { "id": "Al2O3", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -54,
+    "description": "Chromium thermite: aluminium reduces chromium oxide. Used to produce pure chromium",
+    "descriptionRu": "Хромовый термит: алюминий восстанавливает оксид хрома. Производство чистого хрома",
+    "difficulty": 5
+  },
+  {
+    "id": "redox_wo3_al", "type": "redox",
+    "reactants": [{ "id": "WO3", "count": 1 }, { "id": "Al", "count": 2 }],
+    "products": [{ "id": "W", "count": 1 }, { "id": "Al2O3", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -70,
+    "description": "Tungsten extraction: aluminum reduces tungsten oxide to pure metal",
+    "descriptionRu": "Извлечение вольфрама: алюминий восстанавливает оксид вольфрама до чистого металла",
+    "difficulty": 5
+  },
+  {
+    "id": "redox_cuo_c", "type": "redox",
+    "reactants": [{ "id": "CuO", "count": 1 }, { "id": "C", "count": 1 }],
+    "products": [{ "id": "Cu", "count": 1 }, { "id": "CO", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -13,
+    "description": "Ancient copper smelting: carbon reduces copper ore to pure copper",
+    "descriptionRu": "Древняя медеплавка: углерод восстанавливает медную руду до чистой меди",
+    "difficulty": 3
+  },
+  {
+    "id": "redox_pbo_c", "type": "redox",
+    "reactants": [{ "id": "PbO", "count": 1 }, { "id": "C", "count": 1 }],
+    "products": [{ "id": "Pb", "count": 1 }, { "id": "CO", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -11,
+    "description": "Lead smelting: carbon reduces lead oxide to metallic lead",
+    "descriptionRu": "Свинцовая плавка: углерод восстанавливает оксид свинца до металлического свинца",
+    "difficulty": 3
+  },
+  {
+    "id": "redox_fe2o3_c", "type": "redox",
+    "reactants": [{ "id": "Fe2O3", "count": 1 }, { "id": "C", "count": 3 }],
+    "products": [{ "id": "Fe", "count": 2 }, { "id": "CO", "count": 3 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -49,
+    "description": "Iron smelting: carbon reduces iron ore. Foundation of civilization",
+    "descriptionRu": "Выплавка железа: углерод восстанавливает железную руду. Основа цивилизации",
+    "difficulty": 4
+  },
+  {
+    "id": "redox_coo_c", "type": "redox",
+    "reactants": [{ "id": "CoO", "count": 1 }, { "id": "C", "count": 1 }],
+    "products": [{ "id": "Co", "count": 1 }, { "id": "CO", "count": 1 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -10,
+    "description": "Carbon reduces cobalt oxide → pure cobalt. Blue pigment source",
+    "descriptionRu": "Углерод восстанавливает оксид кобальта → чистый кобальт. Источник синего пигмента",
+    "difficulty": 3
+  },
+  {
+    "id": "redox_fe2o3_co", "type": "redox",
+    "reactants": [{ "id": "Fe2O3", "count": 1 }, { "id": "CO", "count": 3 }],
+    "products": [{ "id": "Fe", "count": 2 }, { "id": "CO2", "count": 3 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": -25,
+    "description": "Blast furnace: CO reduces iron ore to iron + CO₂. Industrial steelmaking",
+    "descriptionRu": "Доменная печь: CO восстанавливает железную руду до железа + CO₂. Промышленная металлургия",
+    "difficulty": 4
+  },
+  {
+    "id": "redox_cuo_h", "type": "redox",
+    "reactants": [{ "id": "CuO", "count": 1 }, { "id": "H", "count": 2 }],
+    "products": [{ "id": "Cu", "count": 1 }, { "id": "H2O", "count": 1 }],
+    "conditions": { "minTemp": 500 },
+    "energyChange": -13,
+    "description": "Hydrogen reduces copper oxide → shiny red copper appears + water",
+    "descriptionRu": "Водород восстанавливает оксид меди → появляется блестящая красная медь + вода",
+    "difficulty": 3
+  },
+
+  {
+    "id": "ferment_glucose", "type": "decomposition",
+    "reactants": [{ "id": "C6H12O6", "count": 1 }],
+    "products": [{ "id": "C2H5OH", "count": 2 }, { "id": "CO2", "count": 2 }],
+    "energyChange": -7,
+    "description": "Fermentation: yeast converts glucose → ethanol + CO₂. Birth of brewing and baking",
+    "descriptionRu": "Брожение: дрожжи превращают глюкозу → этанол + CO₂. Рождение пивоварения и хлебопечения",
+    "difficulty": 3
+  },
+  {
+    "id": "decomp_ch3cooh", "type": "decomposition",
+    "reactants": [{ "id": "CH3COOH", "count": 1 }],
+    "products": [{ "id": "C", "count": 2 }, { "id": "H", "count": 4 }, { "id": "O", "count": 2 }],
+    "conditions": { "minTemp": 1000 },
+    "energyChange": 5,
+    "description": "Thermal decomposition of acetic acid at extreme heat",
+    "descriptionRu": "Термическое разложение уксусной кислоты при экстремальном нагреве",
+    "difficulty": 3
   }
 ]

src/data/schools.json

@@ -0,0 +1,113 @@
+[
+  {
+    "id": "alchemist",
+    "name": "Alchemist",
+    "nameRu": "Алхимик",
+    "description": "Master of chemical transformations. Starts with reactive elements and knowledge of chemical equilibrium.",
+    "descriptionRu": "Мастер химических превращений. Начинает с реактивными элементами и знанием химического равновесия.",
+    "startingElements": ["H", "O", "C", "Na", "S", "Fe"],
+    "startingQuantities": {
+      "H": 5,
+      "O": 5,
+      "C": 3,
+      "Na": 3,
+      "S": 2,
+      "Fe": 2
+    },
+    "principle": "Chemical Equilibrium",
+    "principleRu": "Химическое равновесие",
+    "playstyle": "Potions, explosives, poisons. Combine elements for powerful chemical effects.",
+    "playstyleRu": "Зельеварение, взрывчатка, яды. Комбинируй элементы для мощных химических эффектов.",
+    "color": "#00ff88",
+    "bonuses": {
+      "reactionEfficiency": 1.25
+    }
+  },
+  {
+    "id": "mechanic",
+    "name": "Mechanic",
+    "nameRu": "Механик",
+    "description": "Builder of mechanisms and contraptions. Uses leverage and momentum to amplify force.",
+    "descriptionRu": "Строитель механизмов и устройств. Использует рычаг и момент силы для усиления воздействия.",
+    "startingElements": ["Fe", "Cu", "Sn", "Si", "C"],
+    "startingQuantities": {
+      "Fe": 5,
+      "Cu": 4,
+      "Sn": 3,
+      "Si": 4,
+      "C": 4
+    },
+    "principle": "Lever & Moment of Force",
+    "principleRu": "Рычаг и момент силы",
+    "playstyle": "Craft mechanisms, traps, automatons. Metals are your tools.",
+    "playstyleRu": "Крафт механизмов, ловушки, автоматоны. Металлы — твои инструменты.",
+    "color": "#ff8800",
+    "bonuses": {
+      "projectileDamage": 1.3
+    },
+    "unlockCondition": {
+      "type": "elements_discovered",
+      "threshold": 10,
+      "hint": "Discover 10 elements in the Codex",
+      "hintRu": "Открой 10 элементов в Кодексе"
+    }
+  },
+  {
+    "id": "naturalist",
+    "name": "Naturalist",
+    "nameRu": "Натуралист",
+    "description": "Observer of living systems. Understands photosynthesis and ecosystem balance.",
+    "descriptionRu": "Наблюдатель живых систем. Понимает фотосинтез и баланс экосистем.",
+    "startingElements": ["C", "N", "O", "P", "K"],
+    "startingQuantities": {
+      "C": 5,
+      "N": 4,
+      "O": 5,
+      "P": 3,
+      "K": 3
+    },
+    "principle": "Photosynthesis",
+    "principleRu": "Фотосинтез",
+    "playstyle": "Taming, cultivation, ecosystem control. Work with nature, not against it.",
+    "playstyleRu": "Приручение, выращивание, экосистемный контроль. Работай с природой, а не против неё.",
+    "color": "#44cc44",
+    "bonuses": {
+      "creatureAggroRange": 0.6
+    },
+    "unlockCondition": {
+      "type": "creatures_discovered",
+      "threshold": 3,
+      "hint": "Discover 3 creature species",
+      "hintRu": "Открой 3 вида существ"
+    }
+  },
+  {
+    "id": "navigator",
+    "name": "Navigator",
+    "nameRu": "Навигатор",
+    "description": "Master of angles and distances. Charts the unknown with precision and moves with unmatched speed.",
+    "descriptionRu": "Мастер углов и расстояний. Исследует неизведанное с точностью и двигается с непревзойдённой скоростью.",
+    "startingElements": ["Si", "Fe", "C", "H", "O"],
+    "startingQuantities": {
+      "Si": 4,
+      "Fe": 3,
+      "C": 4,
+      "H": 5,
+      "O": 4
+    },
+    "principle": "Angular Measurement",
+    "principleRu": "Угловое измерение",
+    "playstyle": "Cartography, scouting, mobility. See further, move faster.",
+    "playstyleRu": "Картография, разведка, мобильность. Видь дальше, двигайся быстрее.",
+    "color": "#4488ff",
+    "bonuses": {
+      "movementSpeed": 1.2
+    },
+    "unlockCondition": {
+      "type": "runs_completed",
+      "threshold": 3,
+      "hint": "Complete 3 runs",
+      "hintRu": "Заверши 3 рана"
+    }
+  }
+]

src/ecs/bridge.ts

@@ -65,6 +65,11 @@ export class PhaserBridge {
     }
   }
 
+  /** Get the Phaser sprite for an entity (undefined if not yet rendered) */
+  getSprite(eid: number): Phaser.GameObjects.Arc | undefined {
+    return this.spriteMap.get(eid);
+  }
+
   /** Current number of rendered entities */
   get entityCount(): number {
     return this.spriteMap.size;

src/ecs/components.ts

@@ -34,3 +34,86 @@ export const Health = {
 export const ChemicalComposition = {
   primaryElement: [] as number[],  // atomic number (e.g. 11 for Na)
 };
+
+/** Tag component — marks entity as the player (no data, identity only) */
+export const PlayerTag = {
+  _tag: [] as number[],
+};
+
+/** Harvestable resource — mineral veins, geysers, etc. */
+export const Resource = {
+  quantity: [] as number[],       // remaining items to collect
+  interactRange: [] as number[],  // max interaction distance in pixels
+};
+
+/** Thrown element/compound projectile */
+export const Projectile = {
+  lifetime: [] as number[],  // remaining lifetime in ms (removed at 0)
+};
+
+// ─── Creature Components ─────────────────────────────────────────
+
+/** Tag + species identifier for creatures */
+export const Creature = {
+  speciesId: [] as number[],  // SpeciesId enum value (0=Crystallid, 1=Acidophile, 2=Reagent)
+};
+
+/** AI finite state machine */
+export const AI = {
+  state: [] as number[],         // AIState enum value
+  stateTimer: [] as number[],    // ms remaining in current state
+  targetEid: [] as number[],     // entity being pursued/fled (-1 = none)
+  homeX: [] as number[],         // spawn/home position X
+  homeY: [] as number[],         // spawn/home position Y
+  attackCooldown: [] as number[], // ms until next attack allowed
+};
+
+/** Creature metabolism — energy, hunger, feeding */
+export const Metabolism = {
+  energy: [] as number[],        // current energy (0 = starving)
+  energyMax: [] as number[],     // maximum energy capacity
+  drainRate: [] as number[],     // energy lost per second
+  feedAmount: [] as number[],    // energy gained per feeding action
+  hungerThreshold: [] as number[], // fraction (0-1) below which creature seeks food
+};
+
+/** Life cycle stage tracking */
+export const LifeCycle = {
+  stage: [] as number[],       // LifeStage enum value (0=egg, 1=youth, 2=mature, 3=aging)
+  stageTimer: [] as number[],  // ms remaining in current stage
+  age: [] as number[],         // total age in ms
+};
+
+// ─── Boss Components ─────────────────────────────────────────────
+
+/** Boss entity tag + phase info for bridge rendering */
+export const Boss = {
+  dataIndex: [] as number[],     // index in bosses.json array
+  phase: [] as number[],         // BossPhase enum value (synced from BossState)
+  cycleCount: [] as number[],    // completed cycles (synced from BossState)
+};
+
+// ─── World Trace Components (Great Cycle) ────────────────────────
+
+/** A trace left by a previous run — ruin, death marker, discovery site */
+export const WorldTrace = {
+  traceType: [] as number[],    // TraceType enum (0=death_site, 1=discovery_site)
+  sourceRunId: [] as number[],  // which run left this trace
+  glowPhase: [] as number[],   // animation phase for pulsing glow
+  interactRange: [] as number[], // interaction range in pixels
+};
+
+/** TraceType enum values */
+export const TraceType = {
+  DeathSite: 0,
+  DiscoverySite: 1,
+} as const;
+
+// ─── Mycelium Components ─────────────────────────────────────────
+
+/** Fungal node — a point where the Mycelium surfaces on the map */
+export const FungalNode = {
+  nodeIndex: [] as number[],      // index in fungal node info list
+  glowPhase: [] as number[],      // animation phase (radians)
+  interactRange: [] as number[],  // max interaction distance in pixels
+};

src/main.ts

@@ -1,4 +1,7 @@
 import Phaser from 'phaser';
 import { gameConfig } from './config';
 
-new Phaser.Game(gameConfig);
+const game = new Phaser.Game(gameConfig);
+
+// Expose for debug console access
+(window as unknown as Record<string, unknown>).__game = game;

src/mycelium/graph.ts

@@ -0,0 +1,227 @@
+/**
+ * Mycelium Graph — persistent knowledge network
+ *
+ * The graph grows as the player deposits discoveries at fungal nodes.
+ * Nodes represent knowledge (elements, reactions, compounds, creatures).
+ * Edges represent relationships (e.g., elements that form a reaction).
+ *
+ * Strength increases with repeated deposits, decays slightly over time
+ * (knowledge fades if not reinforced).
+ */
+
+import type { MyceliumGraphData, MyceliumNodeData, MyceliumEdgeData, RunState } from '../run/types';
+import type { DepositResult } from './types';
+
+/** Strength increment per deposit (diminishing returns via current strength) */
+const STRENGTH_INCREMENT = 0.2;
+/** Initial strength for a newly created node */
+const INITIAL_STRENGTH = 0.3;
+/** Edge weight for related discoveries */
+const EDGE_WEIGHT = 0.5;
+
+/** Create a new empty Mycelium graph */
+export function createMyceliumGraph(): MyceliumGraphData {
+  return {
+    nodes: [],
+    edges: [],
+    totalDeposits: 0,
+    totalExtractions: 0,
+  };
+}
+
+/**
+ * Deposit all discoveries from a run into the Mycelium graph.
+ *
+ * - Creates new nodes for unknown discoveries
+ * - Strengthens existing nodes for repeated discoveries
+ * - Creates edges between related knowledge (elements↔reactions, reactions↔compounds)
+ */
+export function depositKnowledge(
+  graph: MyceliumGraphData,
+  run: RunState,
+): DepositResult {
+  let newNodes = 0;
+  let strengthened = 0;
+  let newEdges = 0;
+
+  const addedNodeIds: string[] = [];
+
+  // Deposit elements
+  for (const elemId of run.discoveries.elements) {
+    const nodeId = `element:${elemId}`;
+    const result = upsertNode(graph, nodeId, 'element', elemId, run.runId);
+    if (result === 'created') newNodes++;
+    else strengthened++;
+    addedNodeIds.push(nodeId);
+  }
+
+  // Deposit reactions
+  for (const reactionId of run.discoveries.reactions) {
+    const nodeId = `reaction:${reactionId}`;
+    const result = upsertNode(graph, nodeId, 'reaction', reactionId, run.runId);
+    if (result === 'created') newNodes++;
+    else strengthened++;
+    addedNodeIds.push(nodeId);
+  }
+
+  // Deposit compounds
+  for (const compoundId of run.discoveries.compounds) {
+    const nodeId = `compound:${compoundId}`;
+    const result = upsertNode(graph, nodeId, 'compound', compoundId, run.runId);
+    if (result === 'created') newNodes++;
+    else strengthened++;
+    addedNodeIds.push(nodeId);
+  }
+
+  // Deposit creatures
+  for (const creatureId of run.discoveries.creatures) {
+    const nodeId = `creature:${creatureId}`;
+    const result = upsertNode(graph, nodeId, 'creature', creatureId, run.runId);
+    if (result === 'created') newNodes++;
+    else strengthened++;
+    addedNodeIds.push(nodeId);
+  }
+
+  // Create edges between related discoveries
+  // Elements ↔ Reactions (elements that appear in a reaction key)
+  for (const reactionId of run.discoveries.reactions) {
+    const reactionNodeId = `reaction:${reactionId}`;
+    // Parse reaction key (e.g., "Na+Cl" → ["Na", "Cl"])
+    const reactants = reactionId.split('+');
+    for (const reactant of reactants) {
+      const elemNodeId = `element:${reactant}`;
+      if (getNode(graph, elemNodeId)) {
+        const added = upsertEdge(graph, elemNodeId, reactionNodeId);
+        if (added) newEdges++;
+      }
+    }
+  }
+
+  // Reactions ↔ Compounds (reaction produces compound)
+  for (const reactionId of run.discoveries.reactions) {
+    const reactionNodeId = `reaction:${reactionId}`;
+    for (const compoundId of run.discoveries.compounds) {
+      const compoundNodeId = `compound:${compoundId}`;
+      const added = upsertEdge(graph, reactionNodeId, compoundNodeId);
+      if (added) newEdges++;
+    }
+  }
+
+  graph.totalDeposits++;
+
+  return { newNodes, strengthened, newEdges };
+}
+
+/** Get a node by its ID */
+export function getNode(
+  graph: MyceliumGraphData,
+  nodeId: string,
+): MyceliumNodeData | undefined {
+  return graph.nodes.find(n => n.id === nodeId);
+}
+
+/** Get an edge between two nodes */
+export function getEdge(
+  graph: MyceliumGraphData,
+  fromId: string,
+  toId: string,
+): MyceliumEdgeData | undefined {
+  return graph.edges.find(e =>
+    (e.from === fromId && e.to === toId) ||
+    (e.from === toId && e.to === fromId),
+  );
+}
+
+/** Get all nodes of a specific type */
+export function getNodesByType(
+  graph: MyceliumGraphData,
+  type: MyceliumNodeData['type'],
+): MyceliumNodeData[] {
+  return graph.nodes.filter(n => n.type === type);
+}
+
+/** Get nodes connected to a given node (via edges) */
+export function getConnectedNodes(
+  graph: MyceliumGraphData,
+  nodeId: string,
+): MyceliumNodeData[] {
+  const connectedIds = new Set<string>();
+
+  for (const edge of graph.edges) {
+    if (edge.from === nodeId) connectedIds.add(edge.to);
+    if (edge.to === nodeId) connectedIds.add(edge.from);
+  }
+
+  return graph.nodes.filter(n => connectedIds.has(n.id));
+}
+
+/** Get summary statistics of the graph */
+export function getGraphStats(graph: MyceliumGraphData): {
+  nodeCount: number;
+  edgeCount: number;
+  totalDeposits: number;
+  totalExtractions: number;
+  averageStrength: number;
+} {
+  const avgStrength = graph.nodes.length > 0
+    ? graph.nodes.reduce((sum, n) => sum + n.strength, 0) / graph.nodes.length
+    : 0;
+
+  return {
+    nodeCount: graph.nodes.length,
+    edgeCount: graph.edges.length,
+    totalDeposits: graph.totalDeposits,
+    totalExtractions: graph.totalExtractions,
+    averageStrength: avgStrength,
+  };
+}
+
+// ─── Internal helpers ────────────────────────────────────────────
+
+/** Insert or update a knowledge node. Returns 'created' or 'strengthened'. */
+function upsertNode(
+  graph: MyceliumGraphData,
+  nodeId: string,
+  type: MyceliumNodeData['type'],
+  knowledgeId: string,
+  runId: number,
+): 'created' | 'strengthened' {
+  const existing = getNode(graph, nodeId);
+  if (existing) {
+    // Diminishing returns: delta = INCREMENT * (1 - currentStrength)
+    const delta = STRENGTH_INCREMENT * (1 - existing.strength);
+    existing.strength = Math.min(1.0, existing.strength + delta);
+    return 'strengthened';
+  }
+
+  graph.nodes.push({
+    id: nodeId,
+    type,
+    knowledgeId,
+    depositedOnRun: runId,
+    strength: INITIAL_STRENGTH,
+  });
+
+  return 'created';
+}
+
+/** Insert or strengthen an edge. Returns true if newly created. */
+function upsertEdge(
+  graph: MyceliumGraphData,
+  fromId: string,
+  toId: string,
+): boolean {
+  const existing = getEdge(graph, fromId, toId);
+  if (existing) {
+    existing.weight = Math.min(1.0, existing.weight + 0.1);
+    return false;
+  }
+
+  graph.edges.push({
+    from: fromId,
+    to: toId,
+    weight: EDGE_WEIGHT,
+  });
+
+  return true;
+}

src/mycelium/index.ts

@@ -0,0 +1,13 @@
+/**
+ * Mycelium Module — the underground fungal network connecting runs
+ *
+ * Re-exports all public API from mycelium subsystems.
+ */
+
+export { createMyceliumGraph, depositKnowledge, getNode, getEdge, getNodesByType, getConnectedNodes, getGraphStats } from './graph';
+export { extractMemoryFlashes, generateFlashText } from './knowledge';
+export { createMycosisState, updateMycosis, getMycosisVisuals } from './mycosis';
+export { getAvailableBonuses, purchaseBonus, canAffordBonus, resetShopSession } from './shop';
+export { spawnFungalNodes } from './nodes';
+export type { MyceliumKnowledgeNode, MyceliumEdge, MyceliumGraph, MemoryFlash, MycosisState, FungalNodeInfo, SporeBonus, BonusEffect, DepositResult, ExtractResult } from './types';
+export type { MycosisVisuals } from './mycosis';

src/mycelium/knowledge.ts

@@ -0,0 +1,158 @@
+/**
+ * Knowledge System — deposit and extract memories via the Mycelium
+ *
+ * When a player interacts with a fungal node:
+ * - Deposit: current run discoveries are added to the Mycelium graph
+ * - Extract: memory flashes from past runs are surfaced
+ *
+ * Stronger nodes produce clearer, more useful memories.
+ */
+
+import type { MyceliumGraphData, MyceliumNodeData } from '../run/types';
+import type { MemoryFlash } from './types';
+import myceliumData from '../data/mycelium.json';
+
+const templates = myceliumData.memoryTemplates;
+
+/**
+ * Extract memory flashes from the Mycelium graph.
+ *
+ * Selects nodes weighted by strength, generates flash text
+ * for each. Stronger nodes produce higher-clarity flashes.
+ *
+ * @param graph The persistent Mycelium graph
+ * @param maxFlashes Maximum number of flashes to return
+ * @returns Array of memory flashes
+ */
+export function extractMemoryFlashes(
+  graph: MyceliumGraphData,
+  maxFlashes: number,
+): MemoryFlash[] {
+  if (graph.nodes.length === 0) return [];
+
+  graph.totalExtractions++;
+
+  // Weighted random selection: higher strength = more likely
+  const selected = weightedSelect(graph.nodes, maxFlashes);
+
+  return selected.map(node => {
+    const flash = generateFlashText(node.type, node.knowledgeId);
+    flash.sourceRunId = node.depositedOnRun;
+    flash.clarity = node.strength;
+    return flash;
+  });
+}
+
+/**
+ * Generate a memory flash text from templates.
+ *
+ * Replaces {element}, {compound}, {creature} placeholders
+ * with the actual knowledge ID.
+ */
+export function generateFlashText(
+  type: MyceliumNodeData['type'],
+  knowledgeId: string,
+): MemoryFlash {
+  const templateKey = getTemplateKey(type);
+  const templateList = templates[templateKey];
+
+  // Deterministic-ish template selection based on knowledge ID hash
+  const hash = simpleHash(knowledgeId);
+  const template = templateList[hash % templateList.length];
+
+  const text = replaceTokens(template.text, type, knowledgeId);
+  const textRu = replaceTokens(template.textRu, type, knowledgeId);
+
+  return {
+    type: templateKey,
+    text,
+    textRu,
+    sourceRunId: 0,
+    clarity: 0.5,
+  };
+}
+
+// ─── Internal helpers ────────────────────────────────────────────
+
+/** Map node type to template key */
+function getTemplateKey(type: MyceliumNodeData['type']): MemoryFlash['type'] {
+  switch (type) {
+    case 'element': return 'element_hint';
+    case 'reaction': return 'reaction_hint';
+    case 'compound': return 'reaction_hint'; // compounds use reaction templates
+    case 'creature': return 'creature_hint';
+  }
+}
+
+/** Replace template tokens with actual values */
+function replaceTokens(
+  template: string,
+  type: MyceliumNodeData['type'],
+  knowledgeId: string,
+): string {
+  return template
+    .replace('{element}', knowledgeId)
+    .replace('{compound}', knowledgeId)
+    .replace('{creature}', knowledgeId);
+}
+
+/** Simple hash for deterministic template selection */
+function simpleHash(str: string): number {
+  let hash = 0;
+  for (let i = 0; i < str.length; i++) {
+    hash = ((hash << 5) - hash + str.charCodeAt(i)) | 0;
+  }
+  return Math.abs(hash);
+}
+
+/**
+ * Weighted random selection without replacement.
+ * Nodes with higher strength are more likely to be selected.
+ */
+function weightedSelect(
+  nodes: MyceliumNodeData[],
+  count: number,
+): MyceliumNodeData[] {
+  if (nodes.length <= count) return [...nodes];
+
+  const result: MyceliumNodeData[] = [];
+  const used = new Set<number>();
+
+  // Build cumulative weight array
+  const weights = nodes.map(n => n.strength + 0.1); // small base weight
+  const totalWeight = weights.reduce((a, b) => a + b, 0);
+
+  for (let i = 0; i < count && used.size < nodes.length; i++) {
+    let target = pseudoRandom(i + nodes.length) * totalWeight;
+    let idx = 0;
+
+    while (idx < nodes.length) {
+      if (!used.has(idx)) {
+        target -= weights[idx];
+        if (target <= 0) break;
+      }
+      idx++;
+    }
+
+    // Safety: if we went past the end, find first unused
+    if (idx >= nodes.length) {
+      idx = 0;
+      while (used.has(idx) && idx < nodes.length) idx++;
+    }
+
+    if (idx < nodes.length) {
+      result.push(nodes[idx]);
+      used.add(idx);
+    }
+  }
+
+  return result;
+}
+
+/** Pseudo-random 0–1 from integer seed (mulberry32-like) */
+function pseudoRandom(seed: number): number {
+  let t = (seed + 0x6d2b79f5) | 0;
+  t = Math.imul(t ^ (t >>> 15), t | 1);
+  t ^= t + Math.imul(t ^ (t >>> 7), t | 61);
+  return ((t ^ (t >>> 14)) >>> 0) / 4294967296;
+}

src/mycelium/mycosis.ts

@@ -0,0 +1,83 @@
+/**
+ * Mycosis — visual distortion from prolonged contact with fungal nodes
+ *
+ * When the player stays near a fungal node, mycosis level increases.
+ * At the reveal threshold, hidden information becomes visible
+ * (stronger memory flashes, secret details about nearby creatures).
+ *
+ * Moving away from nodes causes mycosis to slowly decay.
+ */
+
+import type { MycosisState } from './types';
+import { MYCOSIS_CONFIG } from './types';
+
+/** Create a fresh mycosis state (no fungal influence) */
+export function createMycosisState(): MycosisState {
+  return {
+    level: 0,
+    exposure: 0,
+    revealing: false,
+  };
+}
+
+/**
+ * Update mycosis state based on proximity to fungal nodes.
+ *
+ * @param state Current mycosis state (mutated in place)
+ * @param deltaMs Time elapsed since last update (ms)
+ * @param nearNode Whether the player is currently near a fungal node
+ */
+export function updateMycosis(
+  state: MycosisState,
+  deltaMs: number,
+  nearNode: boolean,
+): void {
+  const deltaSec = deltaMs / 1000;
+
+  if (nearNode) {
+    // Build up mycosis
+    state.exposure += deltaMs;
+    state.level = Math.min(
+      MYCOSIS_CONFIG.maxLevel,
+      state.level + MYCOSIS_CONFIG.buildRate * deltaSec,
+    );
+  } else {
+    // Decay mycosis
+    state.level = Math.max(
+      0,
+      state.level - MYCOSIS_CONFIG.decayRate * deltaSec,
+    );
+  }
+
+  // Update reveal state
+  state.revealing = state.level >= MYCOSIS_CONFIG.revealThreshold;
+}
+
+/** Visual parameters derived from mycosis level */
+export interface MycosisVisuals {
+  /** Tint overlay color */
+  tintColor: number;
+  /** Tint overlay alpha (0 = invisible, maxTintAlpha = full) */
+  tintAlpha: number;
+  /** Strength of visual distortion (0 = none, 1 = maximum) */
+  distortionStrength: number;
+  /** Whether hidden info should be shown */
+  revealing: boolean;
+}
+
+/**
+ * Get visual parameters for rendering the mycosis effect.
+ *
+ * @param state Current mycosis state
+ * @returns Visual parameters for the renderer
+ */
+export function getMycosisVisuals(state: MycosisState): MycosisVisuals {
+  const fraction = state.level / MYCOSIS_CONFIG.maxLevel;
+
+  return {
+    tintColor: MYCOSIS_CONFIG.tintColor,
+    tintAlpha: fraction * MYCOSIS_CONFIG.maxTintAlpha,
+    distortionStrength: fraction,
+    revealing: state.revealing,
+  };
+}

src/mycelium/nodes.ts

@@ -0,0 +1,131 @@
+/**
+ * Fungal Node Spawning — places Mycelium surface points on the world map
+ *
+ * Fungal nodes are ECS entities placed on walkable tiles during world generation.
+ * They glow softly (bioluminescent green) and pulse gently.
+ * Players interact with them to deposit/extract knowledge.
+ *
+ * Placement uses a Poisson-disc-like approach for even spacing.
+ */
+
+import { addEntity, addComponent } from 'bitecs';
+import type { World } from '../ecs/world';
+import { Position, FungalNode, SpriteRef } from '../ecs/components';
+import type { BiomeData, TileGrid } from '../world/types';
+import type { FungalNodeInfo } from './types';
+import { FUNGAL_NODE_CONFIG } from './types';
+
+/**
+ * Spawn fungal nodes on the world map.
+ *
+ * Algorithm:
+ * 1. Scan grid for tiles listed in FUNGAL_NODE_CONFIG.spawnOnTiles
+ * 2. Deterministically select candidate positions using seed
+ * 3. Filter by minimum spacing constraint
+ * 4. Create ECS entities at selected positions
+ *
+ * @returns Map of entity ID → FungalNodeInfo
+ */
+export function spawnFungalNodes(
+  world: World,
+  grid: TileGrid,
+  biome: BiomeData,
+  seed: number,
+): Map<number, FungalNodeInfo> {
+  const nodeData = new Map<number, FungalNodeInfo>();
+  const tileSize = biome.tileSize;
+
+  // Find tile IDs that fungal nodes can spawn on
+  const spawnTileIds = new Set<number>();
+  for (const tileName of FUNGAL_NODE_CONFIG.spawnOnTiles) {
+    const tile = biome.tiles.find(t => t.name === tileName);
+    if (tile) spawnTileIds.add(tile.id);
+  }
+
+  // Collect all candidate positions (walkable tiles that match spawn targets)
+  const candidates: { x: number; y: number }[] = [];
+  for (let y = 0; y < grid.length; y++) {
+    for (let x = 0; x < grid[y].length; x++) {
+      if (spawnTileIds.has(grid[y][x])) {
+        candidates.push({ x, y });
+      }
+    }
+  }
+
+  if (candidates.length === 0) return nodeData;
+
+  // Determine target node count from map size
+  const mapArea = biome.mapWidth * biome.mapHeight;
+  const targetCount = Math.max(1, Math.round(mapArea * FUNGAL_NODE_CONFIG.targetDensity));
+
+  // Deterministic placement using seed-based scoring
+  const scored = candidates.map(c => ({
+    ...c,
+    score: deterministicScore(c.x, c.y, seed),
+  }));
+
+  // Sort by score (highest first) — deterministic ordering
+  scored.sort((a, b) => b.score - a.score);
+
+  // Select nodes respecting minimum spacing
+  const placed: { x: number; y: number }[] = [];
+  const minSpacing = FUNGAL_NODE_CONFIG.minSpacing;
+
+  for (const candidate of scored) {
+    if (placed.length >= targetCount) break;
+
+    // Check spacing against all placed nodes
+    let tooClose = false;
+    for (const existing of placed) {
+      const dx = candidate.x - existing.x;
+      const dy = candidate.y - existing.y;
+      const dist = Math.sqrt(dx * dx + dy * dy);
+      if (dist < minSpacing) {
+        tooClose = true;
+        break;
+      }
+    }
+
+    if (!tooClose) {
+      placed.push({ x: candidate.x, y: candidate.y });
+    }
+  }
+
+  // Create ECS entities for placed nodes
+  for (let i = 0; i < placed.length; i++) {
+    const pos = placed[i];
+    const eid = addEntity(world);
+
+    addComponent(world, eid, Position);
+    addComponent(world, eid, FungalNode);
+    addComponent(world, eid, SpriteRef);
+
+    Position.x[eid] = pos.x * tileSize + tileSize / 2;
+    Position.y[eid] = pos.y * tileSize + tileSize / 2;
+
+    FungalNode.nodeIndex[eid] = i;
+    FungalNode.glowPhase[eid] = deterministicScore(pos.x, pos.y, seed + 1) * Math.PI * 2;
+    FungalNode.interactRange[eid] = FUNGAL_NODE_CONFIG.interactRange;
+
+    SpriteRef.color[eid] = FUNGAL_NODE_CONFIG.spriteColor;
+    SpriteRef.radius[eid] = FUNGAL_NODE_CONFIG.spriteRadius;
+
+    nodeData.set(eid, {
+      tileX: pos.x,
+      tileY: pos.y,
+      nodeIndex: i,
+    });
+  }
+
+  return nodeData;
+}
+
+/**
+ * Deterministic score for a tile position (0–1).
+ * Higher scores are selected first for node placement.
+ */
+function deterministicScore(x: number, y: number, seed: number): number {
+  // Multiplicative hash for spatial distribution
+  const hash = ((x * 73856093) ^ (y * 19349663) ^ (seed * 83492791)) >>> 0;
+  return (hash % 1000000) / 1000000;
+}

src/mycelium/shop.ts

@@ -0,0 +1,65 @@
+/**
+ * Spore Shop — spend spores for starting bonuses at the Cradle
+ *
+ * Before each run, the player can visit fungal nodes in the Cradle
+ * to exchange spores for:
+ * - Extra health
+ * - Extra starting elements
+ * - Knowledge boost (clearer memory flashes)
+ */
+
+import type { MetaState } from '../run/types';
+import type { SporeBonus, BonusEffect } from './types';
+import myceliumData from '../data/mycelium.json';
+
+const allBonuses = myceliumData.sporeBonuses as SporeBonus[];
+
+/** Track which non-repeatable bonuses have been purchased this session */
+const purchasedNonRepeatableThisSession = new Set<string>();
+
+/** Get all available spore bonuses */
+export function getAvailableBonuses(): SporeBonus[] {
+  return [...allBonuses];
+}
+
+/** Check if the player can afford a specific bonus */
+export function canAffordBonus(meta: MetaState, bonusId: string): boolean {
+  const bonus = allBonuses.find(b => b.id === bonusId);
+  if (!bonus) return false;
+  if (!bonus.repeatable && purchasedNonRepeatableThisSession.has(bonusId)) return false;
+  return meta.spores >= bonus.cost;
+}
+
+/**
+ * Purchase a spore bonus. Deducts spores from meta state.
+ *
+ * @returns The purchased effect, or null if purchase failed
+ */
+export function purchaseBonus(
+  meta: MetaState,
+  bonusId: string,
+): BonusEffect | null {
+  const bonus = allBonuses.find(b => b.id === bonusId);
+  if (!bonus) return null;
+
+  // Check non-repeatable
+  if (!bonus.repeatable && purchasedNonRepeatableThisSession.has(bonusId)) {
+    return null;
+  }
+
+  // Check affordability
+  if (meta.spores < bonus.cost) return null;
+
+  // Deduct and record
+  meta.spores -= bonus.cost;
+  if (!bonus.repeatable) {
+    purchasedNonRepeatableThisSession.add(bonusId);
+  }
+
+  return bonus.effect;
+}
+
+/** Reset purchased tracking (call at start of each Cradle visit) */
+export function resetShopSession(): void {
+  purchasedNonRepeatableThisSession.clear();
+}

src/mycelium/types.ts

@@ -0,0 +1,165 @@
+/**
+ * Mycelium Types — the underground fungal network connecting runs
+ *
+ * The Mycelium is a persistent knowledge graph that grows across runs.
+ * Physical fungal nodes on the world map serve as access points.
+ * Players deposit discoveries and extract memories from past runs.
+ */
+
+// ─── Persistent Graph (stored in MetaState) ─────────────────────
+
+/** A knowledge node in the Mycelium graph */
+export interface MyceliumKnowledgeNode {
+  /** Unique node ID (format: "type:id", e.g. "element:Na") */
+  id: string;
+  /** Knowledge category */
+  type: 'element' | 'reaction' | 'compound' | 'creature';
+  /** Reference to the specific knowledge item */
+  knowledgeId: string;
+  /** Run on which this was first deposited */
+  depositedOnRun: number;
+  /** Knowledge strength 0–1 (increases with repeated deposits) */
+  strength: number;
+}
+
+/** An edge connecting two knowledge nodes */
+export interface MyceliumEdge {
+  /** Source node ID */
+  from: string;
+  /** Target node ID */
+  to: string;
+  /** Connection strength 0–1 */
+  weight: number;
+}
+
+/** The full persistent Mycelium graph */
+export interface MyceliumGraph {
+  /** Knowledge nodes */
+  nodes: MyceliumKnowledgeNode[];
+  /** Connections between nodes */
+  edges: MyceliumEdge[];
+  /** Total deposits across all runs */
+  totalDeposits: number;
+  /** Total extractions across all runs */
+  totalExtractions: number;
+}
+
+// ─── Memory Flashes (retrieved from past runs) ──────────────────
+
+/** A memory fragment surfaced by the Mycelium */
+export interface MemoryFlash {
+  /** What kind of hint this provides */
+  type: 'element_hint' | 'reaction_hint' | 'creature_hint' | 'lore';
+  /** Display text for the player */
+  text: string;
+  /** Display text in Russian */
+  textRu: string;
+  /** Which run deposited this knowledge */
+  sourceRunId: number;
+  /** How clear/strong this memory is (0–1) */
+  clarity: number;
+}
+
+// ─── Mycosis (visual distortion state) ──────────────────────────
+
+/** Player's current mycosis (fungal influence) state */
+export interface MycosisState {
+  /** Current mycosis intensity 0–1 */
+  level: number;
+  /** Accumulated exposure time near fungal nodes (ms) */
+  exposure: number;
+  /** Whether hidden info is currently being revealed */
+  revealing: boolean;
+}
+
+/** Mycosis configuration constants */
+export const MYCOSIS_CONFIG = {
+  /** How fast mycosis builds up (level per second of exposure) */
+  buildRate: 0.08,
+  /** How fast mycosis decays when away from nodes (level per second) */
+  decayRate: 0.03,
+  /** Mycosis level at which hidden information is revealed */
+  revealThreshold: 0.5,
+  /** Maximum mycosis level */
+  maxLevel: 1.0,
+  /** Tint color for mycosis visual effect (greenish-purple) */
+  tintColor: 0x6644aa,
+  /** Maximum tint alpha at full mycosis */
+  maxTintAlpha: 0.25,
+} as const;
+
+// ─── Fungal Nodes (world map entities) ──────────────────────────
+
+/** String data for a fungal node entity (not stored in ECS) */
+export interface FungalNodeInfo {
+  /** Tile position */
+  tileX: number;
+  tileY: number;
+  /** Index in the world's fungal node list */
+  nodeIndex: number;
+}
+
+/** Configuration for fungal node spawning */
+export const FUNGAL_NODE_CONFIG = {
+  /** Interaction range in pixels */
+  interactRange: 48,
+  /** Minimum distance between fungal nodes (in tiles) */
+  minSpacing: 8,
+  /** Target number of nodes per map (adjusted by map size) */
+  targetDensity: 0.003,
+  /** Tiles where fungal nodes can spawn */
+  spawnOnTiles: ['ground', 'scorched-earth'],
+  /** Base glow color (bioluminescent green) */
+  glowColor: 0x44ff88,
+  /** Glow pulse speed (radians per second) */
+  glowPulseSpeed: 1.5,
+  /** Base glow radius in pixels */
+  glowRadius: 6,
+  /** Sprite radius */
+  spriteRadius: 5,
+  /** Sprite color */
+  spriteColor: 0x33cc66,
+} as const;
+
+// ─── Spore Bonuses (Cradle shop) ─────────────────────────────────
+
+/** A purchasable bonus at the Spore Cradle */
+export interface SporeBonus {
+  id: string;
+  name: string;
+  nameRu: string;
+  description: string;
+  descriptionRu: string;
+  /** Spore cost */
+  cost: number;
+  /** Effect applied at run start */
+  effect: BonusEffect;
+  /** Whether this bonus can be purchased multiple times per run */
+  repeatable: boolean;
+}
+
+/** Bonus effect types */
+export type BonusEffect =
+  | { type: 'extra_health'; amount: number }
+  | { type: 'extra_element'; symbol: string; quantity: number }
+  | { type: 'knowledge_boost'; multiplier: number };
+
+// ─── Deposit / Extract results ───────────────────────────────────
+
+/** Result of depositing knowledge at a fungal node */
+export interface DepositResult {
+  /** How many new nodes were added to the graph */
+  newNodes: number;
+  /** How many existing nodes were strengthened */
+  strengthened: number;
+  /** How many new edges were created */
+  newEdges: number;
+}
+
+/** Result of extracting knowledge from a fungal node */
+export interface ExtractResult {
+  /** Memory flashes retrieved */
+  flashes: MemoryFlash[];
+  /** Whether mycosis was triggered/increased */
+  mycosisIncreased: boolean;
+}

src/player/collision.ts

@@ -0,0 +1,128 @@
+/**
+ * Tile Collision System
+ *
+ * Checks player position against tile grid after movement.
+ * Supports wall-sliding: if full movement is blocked, tries
+ * X-only or Y-only to let player slide along walls.
+ */
+
+import { query } from 'bitecs';
+import type { World } from '../ecs/world';
+import { Position, Velocity, PlayerTag } from '../ecs/components';
+import type { TileGrid } from '../world/types';
+import { PLAYER_COLLISION_RADIUS } from './types';
+
+/**
+ * Check if a pixel position falls on a walkable tile.
+ * Returns false for out-of-bounds positions.
+ */
+export function isTileWalkable(
+  px: number,
+  py: number,
+  grid: TileGrid,
+  tileSize: number,
+  walkable: Set<number>,
+): boolean {
+  const tx = Math.floor(px / tileSize);
+  const ty = Math.floor(py / tileSize);
+  if (ty < 0 || ty >= grid.length || tx < 0 || tx >= (grid[0]?.length ?? 0)) {
+    return false;
+  }
+  return walkable.has(grid[ty][tx]);
+}
+
+/**
+ * Check if a circular area (4 corners of bounding box) is on walkable tiles.
+ * Uses AABB corners, not true circle — good enough for small radii.
+ */
+export function isAreaWalkable(
+  x: number,
+  y: number,
+  radius: number,
+  grid: TileGrid,
+  tileSize: number,
+  walkable: Set<number>,
+): boolean {
+  return (
+    isTileWalkable(x - radius, y - radius, grid, tileSize, walkable) &&
+    isTileWalkable(x + radius, y - radius, grid, tileSize, walkable) &&
+    isTileWalkable(x - radius, y + radius, grid, tileSize, walkable) &&
+    isTileWalkable(x + radius, y + radius, grid, tileSize, walkable)
+  );
+}
+
+/**
+ * Resolve position after movement with wall-sliding.
+ *
+ * Priority: full move → X-slide → Y-slide → stay put.
+ * This gives natural wall-sliding behavior.
+ */
+export function resolveCollision(
+  newX: number,
+  newY: number,
+  prevX: number,
+  prevY: number,
+  radius: number,
+  grid: TileGrid,
+  tileSize: number,
+  walkable: Set<number>,
+): { x: number; y: number } {
+  // Full movement valid
+  if (isAreaWalkable(newX, newY, radius, grid, tileSize, walkable)) {
+    return { x: newX, y: newY };
+  }
+  // X-only: slide along Y wall
+  if (isAreaWalkable(newX, prevY, radius, grid, tileSize, walkable)) {
+    return { x: newX, y: prevY };
+  }
+  // Y-only: slide along X wall
+  if (isAreaWalkable(prevX, newY, radius, grid, tileSize, walkable)) {
+    return { x: prevX, y: newY };
+  }
+  // Can't move at all
+  return { x: prevX, y: prevY };
+}
+
+/**
+ * Build a Set of walkable tile IDs from tile data.
+ * Used to quickly check if a tile allows movement.
+ */
+export function buildWalkableSet(
+  tiles: ReadonlyArray<{ id: number; walkable: boolean }>,
+): Set<number> {
+  const set = new Set<number>();
+  for (const tile of tiles) {
+    if (tile.walkable) set.add(tile.id);
+  }
+  return set;
+}
+
+/**
+ * ECS system: resolve tile collisions for player entities.
+ *
+ * Runs AFTER movementSystem. Reconstructs pre-movement position
+ * from current position and velocity, then resolves collision.
+ */
+export function tileCollisionSystem(
+  world: World,
+  deltaMs: number,
+  grid: TileGrid,
+  tileSize: number,
+  walkable: Set<number>,
+): void {
+  const dt = deltaMs / 1000;
+  for (const eid of query(world, [Position, Velocity, PlayerTag])) {
+    const curX = Position.x[eid];
+    const curY = Position.y[eid];
+    // Reconstruct pre-movement position (movementSystem did: pos += vel * dt)
+    const prevX = curX - Velocity.vx[eid] * dt;
+    const prevY = curY - Velocity.vy[eid] * dt;
+
+    const resolved = resolveCollision(
+      curX, curY, prevX, prevY,
+      PLAYER_COLLISION_RADIUS, grid, tileSize, walkable,
+    );
+    Position.x[eid] = resolved.x;
+    Position.y[eid] = resolved.y;
+  }
+}

src/player/crafting.ts

@@ -0,0 +1,102 @@
+/**
+ * Crafting System — Chemistry Engine Integration
+ *
+ * Combines items from inventory using the reaction engine.
+ * On success: consumes reagents, adds products.
+ * On failure: returns educational explanation of why it didn't work.
+ */
+
+import { ReactionEngine } from '../chemistry/engine';
+import type { ReactionConditions, ReactionData } from '../chemistry/types';
+import type { Inventory } from './inventory';
+
+/** What the player wants to combine */
+export interface CraftInput {
+  id: string;    // element symbol or compound id
+  count: number; // quantity to use
+}
+
+/** Result of a crafting attempt */
+export interface CraftResult {
+  success: boolean;
+  /** Products added to inventory (count may differ from reaction output if inventory full) */
+  products?: Array<{ id: string; count: number }>;
+  /** What was consumed from inventory */
+  consumedReactants?: CraftInput[];
+  /** Reaction data (for codex, description display) */
+  reaction?: ReactionData;
+  /** Why it failed (English) */
+  failureReason?: string;
+  /** Why it failed (Russian) */
+  failureReasonRu?: string;
+}
+
+/**
+ * Attempt to craft from inventory items.
+ *
+ * 1. Checks inventory has all reagents
+ * 2. Runs reaction engine (O(1) lookup + condition check)
+ * 3. On success: consumes reagents, adds products
+ * 4. On failure: returns educational reason
+ *
+ * Reagents are only consumed on success — failed attempts are free.
+ */
+export function craftFromInventory(
+  inventory: Inventory,
+  reactants: CraftInput[],
+  conditions?: Partial<ReactionConditions>,
+): CraftResult {
+  // Empty input
+  if (reactants.length === 0) {
+    return {
+      success: false,
+      failureReason: 'Select at least one substance to combine.',
+      failureReasonRu: 'Выберите хотя бы одно вещество для комбинирования.',
+    };
+  }
+
+  // 1. Check inventory has all reagents
+  for (const r of reactants) {
+    const have = inventory.getCount(r.id);
+    if (have < r.count) {
+      return {
+        success: false,
+        failureReason: `Not enough ${r.id} — have ${have}, need ${r.count}.`,
+        failureReasonRu: `Недостаточно ${r.id} — есть ${have}, нужно ${r.count}.`,
+      };
+    }
+  }
+
+  // 2. Run reaction engine
+  const result = ReactionEngine.react(
+    reactants.map(r => ({ id: r.id, count: r.count })),
+    conditions,
+  );
+
+  if (!result.success) {
+    return {
+      success: false,
+      failureReason: result.failureReason,
+      failureReasonRu: result.failureReasonRu,
+    };
+  }
+
+  // 3. Consume reagents
+  for (const r of reactants) {
+    inventory.removeItem(r.id, r.count);
+  }
+
+  // 4. Add products to inventory
+  const addedProducts: Array<{ id: string; count: number }> = [];
+  for (const p of result.products!) {
+    const added = inventory.addItem(p.id, p.count);
+    addedProducts.push({ id: p.id, count: added });
+  }
+
+  return {
+    success: true,
+    products: addedProducts,
+    consumedReactants: reactants,
+    reaction: result.reaction,
+  };
+}

src/player/factory.ts

@@ -0,0 +1,31 @@
+/**
+ * Player Entity Factory
+ *
+ * Creates the player entity with all required components:
+ * Position, Velocity, SpriteRef, Health, PlayerTag.
+ */
+
+import { addComponent } from 'bitecs';
+import type { World } from '../ecs/world';
+import { PlayerTag } from '../ecs/components';
+import { createGameEntity } from '../ecs/factory';
+import { PLAYER_COLOR, PLAYER_RADIUS, PLAYER_HEALTH } from './types';
+
+/**
+ * Create the player entity at the given position.
+ * @returns entity ID (eid)
+ */
+export function createPlayerEntity(
+  world: World,
+  x: number,
+  y: number,
+): number {
+  const eid = createGameEntity(world, {
+    position: { x, y },
+    velocity: { vx: 0, vy: 0 },
+    health: { current: PLAYER_HEALTH, max: PLAYER_HEALTH },
+    sprite: { color: PLAYER_COLOR, radius: PLAYER_RADIUS },
+  });
+  addComponent(world, eid, PlayerTag);
+  return eid;
+}

src/player/input.ts

@@ -0,0 +1,50 @@
+/**
+ * Player Input System
+ *
+ * Reads InputState → sets player entity Velocity.
+ * Diagonal movement is normalized to prevent faster diagonal speed.
+ */
+
+import { query } from 'bitecs';
+import type { World } from '../ecs/world';
+import { Velocity, PlayerTag } from '../ecs/components';
+import type { InputState } from './types';
+import { PLAYER_SPEED } from './types';
+
+/**
+ * Calculate velocity vector from input state (pure function).
+ * Diagonal movement is normalized so magnitude = speed.
+ */
+export function calculatePlayerVelocity(
+  input: InputState,
+  speed: number,
+): { vx: number; vy: number } {
+  const { moveX, moveY } = input;
+
+  if (moveX === 0 && moveY === 0) {
+    return { vx: 0, vy: 0 };
+  }
+
+  // Normalize diagonal so total speed stays constant
+  const isDiagonal = moveX !== 0 && moveY !== 0;
+  const factor = isDiagonal ? 1 / Math.SQRT2 : 1;
+
+  return {
+    vx: moveX * speed * factor,
+    vy: moveY * speed * factor,
+  };
+}
+
+/**
+ * ECS system: set player entity velocity from input.
+ * Only affects entities with PlayerTag + Velocity.
+ *
+ * @param speedMultiplier — optional multiplier on base PLAYER_SPEED (default 1.0)
+ */
+export function playerInputSystem(world: World, input: InputState, speedMultiplier = 1.0): void {
+  const vel = calculatePlayerVelocity(input, PLAYER_SPEED * speedMultiplier);
+  for (const eid of query(world, [Velocity, PlayerTag])) {
+    Velocity.vx[eid] = vel.vx;
+    Velocity.vy[eid] = vel.vy;
+  }
+}

src/player/interaction.ts

@@ -0,0 +1,114 @@
+/**
+ * Resource Interaction System — Phase 4.3
+ *
+ * Handles player collecting elements from world resources
+ * (mineral veins, geysers). Press E near a resource to collect.
+ */
+
+import { query } from 'bitecs';
+import type { World } from '../ecs/world';
+import { Position, Resource, PlayerTag } from '../ecs/components';
+import { removeGameEntity } from '../ecs/factory';
+import type { Inventory } from './inventory';
+
+/** Metadata for a resource entity (string data that can't go in bitECS arrays) */
+export interface ResourceInfo {
+  itemId: string;   // element symbol or compound id
+  tileX: number;
+  tileY: number;
+}
+
+/** Result of an interaction attempt */
+export interface InteractionResult {
+  type: 'collected' | 'depleted' | 'inventory_full' | 'nothing_nearby';
+  itemId?: string;
+  remaining?: number;
+}
+
+/** Elements that mineral veins can yield */
+export const MINERAL_ELEMENTS = ['Fe', 'Cu', 'Zn', 'Au', 'Sn'] as const;
+
+/** Elements that geysers can yield */
+export const GEYSER_ELEMENTS = ['S', 'H'] as const;
+
+/**
+ * Deterministic element picker based on tile position and seed.
+ * Same (x, y, seed) always gives the same element.
+ */
+export function pickResourceElement(
+  tileX: number,
+  tileY: number,
+  seed: number,
+  options: readonly string[],
+): string {
+  // Multiplicative hash for spatial distribution
+  const hash = ((tileX * 73856093) ^ (tileY * 19349663) ^ (seed * 83492791)) >>> 0;
+  return options[hash % options.length];
+}
+
+/**
+ * Interaction system — handles E-key resource collection.
+ *
+ * Finds closest resource in range, adds to inventory, decrements quantity.
+ * Returns null if E not pressed, or InteractionResult describing what happened.
+ */
+export function interactionSystem(
+  world: World,
+  justPressedInteract: boolean,
+  inventory: Inventory,
+  resourceData: Map<number, ResourceInfo>,
+): InteractionResult | null {
+  if (!justPressedInteract) return null;
+
+  // Find player position
+  const players = query(world, [Position, PlayerTag]);
+  if (players.length === 0) return null;
+  const playerEid = players[0];
+  const px = Position.x[playerEid];
+  const py = Position.y[playerEid];
+
+  // Find closest resource in range
+  let closestEid: number | null = null;
+  let closestDist = Infinity;
+
+  for (const eid of query(world, [Position, Resource])) {
+    const dx = Position.x[eid] - px;
+    const dy = Position.y[eid] - py;
+    const dist = Math.sqrt(dx * dx + dy * dy);
+    const range = Resource.interactRange[eid];
+
+    if (dist <= range && dist < closestDist) {
+      closestEid = eid;
+      closestDist = dist;
+    }
+  }
+
+  if (closestEid === null) {
+    return { type: 'nothing_nearby' };
+  }
+
+  const info = resourceData.get(closestEid);
+  if (!info) return { type: 'nothing_nearby' };
+
+  // Try to add to inventory
+  const added = inventory.addItem(info.itemId, 1);
+  if (added === 0) {
+    return { type: 'inventory_full', itemId: info.itemId };
+  }
+
+  // Decrement resource quantity
+  Resource.quantity[closestEid] -= 1;
+
+  if (Resource.quantity[closestEid] <= 0) {
+    // Resource depleted — remove entity
+    removeGameEntity(world, closestEid);
+    resourceData.delete(closestEid);
+    return { type: 'depleted', itemId: info.itemId };
+  }
+
+  return {
+    type: 'collected',
+    itemId: info.itemId,
+    remaining: Resource.quantity[closestEid],
+  };
+}

src/player/inventory.ts

@@ -0,0 +1,149 @@
+/**
+ * Player Inventory — Weight-Based with Element Stacking
+ *
+ * Items are elements (by symbol) or compounds (by id).
+ * Weight = real atomic/molecular mass.
+ * Same items stack automatically (count increases).
+ */
+
+import { ElementRegistry } from '../chemistry/elements';
+import { CompoundRegistry } from '../chemistry/compounds';
+
+/** A single inventory entry */
+export interface InventoryItem {
+  readonly id: string;
+  readonly count: number;
+}
+
+/**
+ * Get the mass of an item (element or compound).
+ * Returns atomic mass for elements, molecular mass for compounds, 0 for unknown.
+ */
+export function getItemMass(id: string): number {
+  const el = ElementRegistry.getBySymbol(id);
+  if (el) return el.atomicMass;
+
+  const comp = CompoundRegistry.getById(id);
+  if (comp) return comp.mass;
+
+  return 0;
+}
+
+/**
+ * Weight-based inventory with slot limits and auto-stacking.
+ *
+ * Weight uses real atomic/molecular masses (AMU).
+ * Same items stack into a single slot.
+ */
+export class Inventory {
+  private counts = new Map<string, number>();
+
+  /** Maximum total weight (AMU) */
+  readonly maxWeight: number;
+  /** Maximum number of unique item types (slots) */
+  readonly maxSlots: number;
+
+  constructor(maxWeight = 500, maxSlots = 20) {
+    this.maxWeight = maxWeight;
+    this.maxSlots = maxSlots;
+  }
+
+  /**
+   * Add items to inventory.
+   * @returns actual count added (may be less if weight limit reached, 0 if impossible)
+   */
+  addItem(id: string, count = 1): number {
+    if (count <= 0) return 0;
+
+    const mass = getItemMass(id);
+    if (mass <= 0) return 0;
+
+    // New item needs an available slot
+    const isNewItem = !this.counts.has(id);
+    if (isNewItem && this.counts.size >= this.maxSlots) return 0;
+
+    // Calculate how many can fit by weight
+    const currentWeight = this.getTotalWeight();
+    const spaceLeft = this.maxWeight - currentWeight;
+    const maxByWeight = Math.floor(spaceLeft / mass);
+    const actualAdd = Math.min(count, maxByWeight);
+
+    if (actualAdd <= 0) return 0;
+
+    const existing = this.counts.get(id) ?? 0;
+    this.counts.set(id, existing + actualAdd);
+
+    return actualAdd;
+  }
+
+  /**
+   * Remove items from inventory.
+   * @returns actual count removed (may be less if not enough in stock)
+   */
+  removeItem(id: string, count = 1): number {
+    if (count <= 0) return 0;
+
+    const current = this.counts.get(id) ?? 0;
+    if (current <= 0) return 0;
+
+    const actualRemove = Math.min(count, current);
+    const newCount = current - actualRemove;
+
+    if (newCount <= 0) {
+      this.counts.delete(id);
+    } else {
+      this.counts.set(id, newCount);
+    }
+
+    return actualRemove;
+  }
+
+  /** Get item count (0 if not in inventory) */
+  getCount(id: string): number {
+    return this.counts.get(id) ?? 0;
+  }
+
+  /** Check if inventory has at least `count` of an item */
+  hasItem(id: string, count = 1): boolean {
+    return (this.counts.get(id) ?? 0) >= count;
+  }
+
+  /** Get all items as array of { id, count } */
+  getItems(): InventoryItem[] {
+    const items: InventoryItem[] = [];
+    for (const [id, count] of this.counts) {
+      items.push({ id, count });
+    }
+    return items;
+  }
+
+  /** Total weight of all items (sum of mass * count) */
+  getTotalWeight(): number {
+    let total = 0;
+    for (const [id, count] of this.counts) {
+      total += getItemMass(id) * count;
+    }
+    return total;
+  }
+
+  /** Weight of a single item stack */
+  getItemWeight(id: string): number {
+    const count = this.counts.get(id) ?? 0;
+    return getItemMass(id) * count;
+  }
+
+  /** Number of unique item types (occupied slots) */
+  get slotCount(): number {
+    return this.counts.size;
+  }
+
+  /** Whether inventory has zero items */
+  isEmpty(): boolean {
+    return this.counts.size === 0;
+  }
+
+  /** Remove all items */
+  clear(): void {
+    this.counts.clear();
+  }
+}

src/player/projectile.ts

@@ -0,0 +1,141 @@
+/**
+ * Projectile System — Throw Elements & Compounds
+ *
+ * Player launches projectiles toward mouse cursor.
+ * Projectiles travel in a straight line, expire after a lifetime,
+ * and are destroyed on hitting non-walkable tiles.
+ */
+
+import { addEntity, addComponent, query } from 'bitecs';
+import type { World } from '../ecs/world';
+import { Position, Velocity, SpriteRef, Projectile } from '../ecs/components';
+import { removeGameEntity } from '../ecs/factory';
+import { isTileWalkable } from './collision';
+import { ElementRegistry } from '../chemistry/elements';
+import { CompoundRegistry } from '../chemistry/compounds';
+import type { TileGrid } from '../world/types';
+
+/** Extra data for a projectile entity (string data) */
+export interface ProjectileData {
+  itemId: string;  // element symbol or compound id
+}
+
+// === Constants ===
+
+/** Projectile flight speed in pixels per second */
+export const PROJECTILE_SPEED = 350;
+
+/** Projectile lifetime in milliseconds */
+export const PROJECTILE_LIFETIME = 2000;
+
+/** Projectile visual radius */
+export const PROJECTILE_RADIUS = 5;
+
+// === Direction ===
+
+/**
+ * Calculate normalized direction from source to target.
+ * Returns (1, 0) if source == target (default: right).
+ */
+export function calculateDirection(
+  fromX: number, fromY: number,
+  toX: number, toY: number,
+): { dx: number; dy: number } {
+  const dx = toX - fromX;
+  const dy = toY - fromY;
+  const len = Math.sqrt(dx * dx + dy * dy);
+
+  if (len < 0.001) {
+    return { dx: 1, dy: 0 }; // default direction
+  }
+
+  return { dx: dx / len, dy: dy / len };
+}
+
+// === Launch ===
+
+/**
+ * Get the display color for a chemical item.
+ * Uses element color from registry, or compound color, or default white.
+ */
+function getItemColor(itemId: string): number {
+  const el = ElementRegistry.getBySymbol(itemId);
+  if (el) return parseInt(el.color.replace('#', ''), 16);
+
+  const comp = CompoundRegistry.getById(itemId);
+  if (comp) return parseInt(comp.color.replace('#', ''), 16);
+
+  return 0xffffff;
+}
+
+/**
+ * Create a projectile entity flying from (fromX, fromY) toward (toX, toY).
+ * @returns entity ID
+ */
+export function launchProjectile(
+  world: World,
+  projData: Map<number, ProjectileData>,
+  fromX: number,
+  fromY: number,
+  toX: number,
+  toY: number,
+  itemId: string,
+): number {
+  const dir = calculateDirection(fromX, fromY, toX, toY);
+
+  const eid = addEntity(world);
+  addComponent(world, eid, Position);
+  addComponent(world, eid, Velocity);
+  addComponent(world, eid, SpriteRef);
+  addComponent(world, eid, Projectile);
+
+  Position.x[eid] = fromX;
+  Position.y[eid] = fromY;
+  Velocity.vx[eid] = dir.dx * PROJECTILE_SPEED;
+  Velocity.vy[eid] = dir.dy * PROJECTILE_SPEED;
+  SpriteRef.color[eid] = getItemColor(itemId);
+  SpriteRef.radius[eid] = PROJECTILE_RADIUS;
+  Projectile.lifetime[eid] = PROJECTILE_LIFETIME;
+
+  projData.set(eid, { itemId });
+
+  return eid;
+}
+
+// === System ===
+
+/**
+ * Update projectiles: decrement lifetime, remove expired/collided.
+ * Runs AFTER movementSystem (projectiles moved by generic movement).
+ */
+export function projectileSystem(
+  world: World,
+  deltaMs: number,
+  grid: TileGrid,
+  tileSize: number,
+  walkable: Set<number>,
+  projData: Map<number, ProjectileData>,
+): void {
+  const toRemove: number[] = [];
+
+  for (const eid of query(world, [Position, Projectile])) {
+    // Decrement lifetime
+    Projectile.lifetime[eid] -= deltaMs;
+
+    // Check expiry
+    if (Projectile.lifetime[eid] <= 0) {
+      toRemove.push(eid);
+      continue;
+    }
+
+    // Check tile collision (point check at projectile center)
+    if (!isTileWalkable(Position.x[eid], Position.y[eid], grid, tileSize, walkable)) {
+      toRemove.push(eid);
+    }
+  }
+
+  for (const eid of toRemove) {
+    removeGameEntity(world, eid);
+    projData.delete(eid);
+  }
+}

src/player/quickslots.ts

@@ -0,0 +1,66 @@
+/**
+ * Quick Slots — 4 Hotkey Slots for Fast Item Access
+ *
+ * Keys 1-4 select active slot. Active slot determines
+ * what gets thrown (F) or used. Items are referenced
+ * by id from the inventory.
+ */
+
+/** Number of quick slots */
+export const SLOT_COUNT = 4;
+
+/**
+ * Quick slots manager.
+ * Stores item ids assigned to 4 slots (keys 1-4).
+ * Active slot determines current "equipped" item.
+ */
+export class QuickSlots {
+  private slots: (string | null)[] = new Array(SLOT_COUNT).fill(null);
+
+  /** Currently active slot index (0-3) */
+  activeIndex = 0;
+
+  /** Assign an item id to a slot (null to clear) */
+  assign(index: number, itemId: string | null): void {
+    if (index < 0 || index >= SLOT_COUNT) return;
+    this.slots[index] = itemId;
+  }
+
+  /** Get item id in a slot (null if empty) */
+  getSlot(index: number): string | null {
+    if (index < 0 || index >= SLOT_COUNT) return null;
+    return this.slots[index];
+  }
+
+  /** Get item id in the active slot */
+  getActive(): string | null {
+    return this.slots[this.activeIndex];
+  }
+
+  /** Set active slot index (clamped to valid range) */
+  setActive(index: number): void {
+    this.activeIndex = Math.max(0, Math.min(SLOT_COUNT - 1, index));
+  }
+
+  /** Get all slot contents as array */
+  getAll(): (string | null)[] {
+    return [...this.slots];
+  }
+
+  /**
+   * Auto-assign an item to the first empty slot.
+   * Returns slot index, or -1 if no empty slot or item already assigned.
+   */
+  autoAssign(itemId: string): number {
+    // Don't duplicate
+    if (this.slots.includes(itemId)) return -1;
+
+    for (let i = 0; i < SLOT_COUNT; i++) {
+      if (this.slots[i] === null) {
+        this.slots[i] = itemId;
+        return i;
+      }
+    }
+    return -1;
+  }
+}

src/player/spawn.ts

@@ -0,0 +1,51 @@
+/**
+ * Player Spawn Position
+ *
+ * Finds a walkable tile near the center of the map.
+ * Spirals outward from center to find the nearest valid spawn.
+ */
+
+import type { TileGrid } from '../world/types';
+
+/**
+ * Find a walkable spawn position, starting from map center.
+ * Returns pixel coordinates (center of tile) or null if no walkable tile exists.
+ */
+export function findSpawnPosition(
+  grid: TileGrid,
+  tileSize: number,
+  walkable: Set<number>,
+): { x: number; y: number } | null {
+  const height = grid.length;
+  if (height === 0) return null;
+  const width = grid[0].length;
+  if (width === 0) return null;
+
+  const centerY = Math.floor(height / 2);
+  const centerX = Math.floor(width / 2);
+
+  // Spiral outward from center
+  const maxRadius = Math.max(width, height);
+  for (let r = 0; r <= maxRadius; r++) {
+    for (let dy = -r; dy <= r; dy++) {
+      for (let dx = -r; dx <= r; dx++) {
+        // Only check perimeter of ring (interior was checked in smaller radius)
+        if (r > 0 && Math.abs(dx) < r && Math.abs(dy) < r) continue;
+
+        const ty = centerY + dy;
+        const tx = centerX + dx;
+
+        if (ty >= 0 && ty < height && tx >= 0 && tx < width) {
+          if (walkable.has(grid[ty][tx])) {
+            return {
+              x: tx * tileSize + tileSize / 2,
+              y: ty * tileSize + tileSize / 2,
+            };
+          }
+        }
+      }
+    }
+  }
+
+  return null;
+}

src/player/types.ts

@@ -0,0 +1,33 @@
+/**
+ * Player Types & Constants
+ *
+ * InputState represents the current frame's player input.
+ * Constants define player attributes (speed, size, health, color).
+ */
+
+/** Keyboard/gamepad state for current frame */
+export interface InputState {
+  /** Horizontal axis: -1 (left), 0 (none), +1 (right) */
+  moveX: number;
+  /** Vertical axis: -1 (up), 0 (none), +1 (down) */
+  moveY: number;
+  /** Interact key (E) pressed */
+  interact: boolean;
+}
+
+// === Player Constants ===
+
+/** Movement speed in pixels per second */
+export const PLAYER_SPEED = 150;
+
+/** Collision radius in pixels (smaller than visual for forgiving feel) */
+export const PLAYER_COLLISION_RADIUS = 6;
+
+/** Starting and maximum health */
+export const PLAYER_HEALTH = 100;
+
+/** Visual color (bright cyan — stands out on dark biome) */
+export const PLAYER_COLOR = 0x00e5ff;
+
+/** Visual radius in pixels */
+export const PLAYER_RADIUS = 10;

src/run/crisis.ts

@@ -0,0 +1,105 @@
+/**
+ * Crisis System — Chemical Plague
+ *
+ * When escalation reaches its threshold, a crisis activates.
+ * The Chemical Plague poisons the atmosphere — player must craft
+ * the correct neutralizing compound to stop it.
+ */
+
+import type { CrisisConfig } from './types';
+
+// ─── Chemical Plague Configuration ───────────────────────────────
+
+export const CHEMICAL_PLAGUE: CrisisConfig = {
+  type: 'chemical-plague',
+  name: 'Chemical Plague',
+  nameRu: 'Химическая Чума',
+  description: 'A chain reaction is poisoning the atmosphere. Neutralize it with the right compound!',
+  descriptionRu: 'Цепная реакция отравляет атмосферу. Нейтрализуй правильным соединением!',
+  triggerThreshold: 0.8,
+  neutralizer: 'CaO',       // Calcium oxide (quicklime) — absorbs acid gases
+  neutralizeAmount: 3,       // need 3 units to fully neutralize
+};
+
+// ─── Crisis State ────────────────────────────────────────────────
+
+export interface CrisisState {
+  config: CrisisConfig;
+  active: boolean;
+  /** Progress 0.0–1.0 — at 1.0 the world is fully poisoned */
+  progress: number;
+  resolved: boolean;
+  /** How many neutralizer units have been applied */
+  neutralizeApplied: number;
+}
+
+/** Damage growth rate per second during active crisis */
+const CRISIS_DAMAGE_RATE = 0.01; // reaches 1.0 in ~100 seconds
+
+/** Create a new crisis state from config */
+export function createCrisisState(config: CrisisConfig): CrisisState {
+  return {
+    config,
+    active: true,
+    progress: 0,
+    resolved: false,
+    neutralizeApplied: 0,
+  };
+}
+
+/** Advance crisis damage over time */
+export function applyCrisisDamage(crisis: CrisisState, deltaMs: number): void {
+  if (!crisis.active || crisis.resolved) return;
+  const deltaSec = deltaMs / 1000;
+  crisis.progress = Math.min(1.0, crisis.progress + CRISIS_DAMAGE_RATE * deltaSec);
+}
+
+/** Attempt to neutralize the crisis with a compound. Returns true if correct compound. */
+export function attemptNeutralize(
+  crisis: CrisisState,
+  compoundId: string,
+  amount: number,
+): boolean {
+  if (compoundId !== crisis.config.neutralizer) return false;
+  if (crisis.resolved) return true;
+
+  crisis.neutralizeApplied += amount;
+
+  // Reduce progress proportionally
+  const reductionPerUnit = 1.0 / crisis.config.neutralizeAmount;
+  crisis.progress = Math.max(0, crisis.progress - amount * reductionPerUnit);
+
+  // Check if fully neutralized
+  if (crisis.neutralizeApplied >= crisis.config.neutralizeAmount) {
+    crisis.resolved = true;
+    crisis.active = false;
+    crisis.progress = 0;
+  }
+
+  return true;
+}
+
+/** Check if crisis has been resolved */
+export function isCrisisResolved(crisis: CrisisState): boolean {
+  return crisis.resolved;
+}
+
+/** Calculate player damage per frame from active crisis */
+export function getCrisisPlayerDamage(crisis: CrisisState, deltaMs: number): number {
+  if (crisis.resolved || crisis.progress <= 0.3) return 0;
+  const deltaSec = deltaMs / 1000;
+  // Damage scales with how far above 30% threshold
+  return (crisis.progress - 0.3) * 0.7 * deltaSec;
+}
+
+/** Get visual tint for crisis overlay */
+export function getCrisisTint(crisis: CrisisState): { color: number; alpha: number } {
+  if (crisis.resolved || crisis.progress <= 0) {
+    return { color: 0x88ff88, alpha: 0 };
+  }
+  // Green toxic tint that intensifies with progress
+  return {
+    color: 0x88ff88,
+    alpha: Math.min(0.15, crisis.progress * 0.15),
+  };
+}

src/run/cycle.ts

@@ -0,0 +1,220 @@
+/**
+ * Great Cycle System — 7-run macro cycles with traces between runs
+ *
+ * GDD spec (Section IV):
+ * - Every 7 runs = 1 Great Cycle
+ * - After 7th run → Great Renewal: world changes, lore unlocks, Mycelium matures
+ * - Previous 7 runs leave concrete traces: ruins, consequences, mutated creatures
+ * - Each cycle has a narrative theme (Awakening → Doubt → Realization → ...)
+ *
+ * Three Laws of Arcana:
+ * 1. Law of Return — everything that was, will be again, but never exactly the same
+ * 2. Law of Trace — nothing disappears without a trace
+ * 3. Law of Synthesis — when all knowledge fragments connect, the cycle transcends
+ */
+
+import type {
+  GreatCycleState,
+  RunTrace,
+  RunState,
+  MetaState,
+  CycleTheme,
+  CycleWorldModifiers,
+} from './types';
+import { CYCLE_THEMES, RUNS_PER_CYCLE, RunPhase } from './types';
+import { countDiscoveries } from './state';
+
+// ─── Initialization ──────────────────────────────────────────────
+
+/** Create initial great cycle state (first time playing) */
+export function createGreatCycleState(): GreatCycleState {
+  return {
+    cycleNumber: 1,
+    runInCycle: 1,
+    theme: 'awakening',
+    currentCycleTraces: [],
+    previousCycleTraces: [],
+    renewalsCompleted: 0,
+    myceliumMaturation: 0,
+  };
+}
+
+// ─── Theme Resolution ────────────────────────────────────────────
+
+/** Get the cycle theme for a given cycle number (1-based) */
+export function getCycleTheme(cycleNumber: number): CycleTheme {
+  if (cycleNumber < 1) return 'awakening';
+  const idx = Math.min(cycleNumber - 1, CYCLE_THEMES.length - 1);
+  return CYCLE_THEMES[idx];
+}
+
+// ─── Run Trace Recording ─────────────────────────────────────────
+
+/**
+ * Create a RunTrace from a completed run state.
+ * Called when a run ends (death or boss victory).
+ */
+export function createRunTrace(
+  run: RunState,
+  cycleState: GreatCycleState,
+): RunTrace {
+  // Extract up to 5 key element discoveries for trace markers
+  const keyElements = Array.from(run.discoveries.elements).slice(0, 5);
+
+  return {
+    runId: run.runId,
+    runInCycle: cycleState.runInCycle,
+    schoolId: run.schoolId,
+    biomeId: run.biomeId,
+    deathPosition: run.deathPosition,
+    phaseReached: run.phase,
+    crisisResolved: run.crisisResolved,
+    discoveryCount: countDiscoveries(run),
+    keyElements,
+    duration: run.elapsed,
+    worldSeed: run.worldSeed,
+  };
+}
+
+/**
+ * Record a completed run's trace and advance the cycle.
+ * Returns true if this run triggers a Great Renewal (every 7th run).
+ */
+export function recordRunAndAdvanceCycle(
+  meta: MetaState,
+  run: RunState,
+): boolean {
+  const cycle = meta.greatCycle;
+  const trace = createRunTrace(run, cycle);
+
+  // Add trace to current cycle
+  cycle.currentCycleTraces.push(trace);
+
+  // Check if this completes a great cycle
+  const isRenewal = cycle.runInCycle >= RUNS_PER_CYCLE;
+
+  if (isRenewal) {
+    // Great Renewal!
+    performGreatRenewal(meta);
+  } else {
+    // Advance to next run within the cycle
+    cycle.runInCycle += 1;
+  }
+
+  return isRenewal;
+}
+
+// ─── Great Renewal ───────────────────────────────────────────────
+
+/**
+ * Perform the Great Renewal — transitions between great cycles.
+ *
+ * GDD spec:
+ * - World generation fundamentally changes
+ * - New lore layer unlocks
+ * - Mycelium "matures" — opens new capabilities
+ * - Previous 7 runs' traces become "previous cycle" traces
+ */
+export function performGreatRenewal(meta: MetaState): void {
+  const cycle = meta.greatCycle;
+
+  // Move current traces to previous (only keep last cycle's traces)
+  cycle.previousCycleTraces = [...cycle.currentCycleTraces];
+  cycle.currentCycleTraces = [];
+
+  // Advance cycle number
+  cycle.cycleNumber += 1;
+  cycle.runInCycle = 1;
+  cycle.theme = getCycleTheme(cycle.cycleNumber);
+  cycle.renewalsCompleted += 1;
+
+  // Mycelium maturation: each renewal strengthens the network
+  cycle.myceliumMaturation = Math.min(
+    cycle.myceliumMaturation + 0.15,
+    1.0,
+  );
+
+  // Strengthen all Mycelium nodes on renewal
+  strengthenMyceliumOnRenewal(meta);
+}
+
+/**
+ * Strengthen Mycelium nodes during Great Renewal.
+ * All nodes gain strength proportional to the maturation level.
+ */
+function strengthenMyceliumOnRenewal(meta: MetaState): void {
+  const bonus = 0.1 + meta.greatCycle.myceliumMaturation * 0.1;
+  for (const node of meta.mycelium.nodes) {
+    node.strength = Math.min(1.0, node.strength + bonus);
+  }
+}
+
+// ─── World Modifiers ─────────────────────────────────────────────
+
+/**
+ * Get world generation modifiers based on cycle number.
+ * Higher cycles = more varied/challenging worlds.
+ *
+ * GDD: "Fundamentally changes generation (new biome types, different proportions)"
+ */
+export function getCycleWorldModifiers(cycleNumber: number): CycleWorldModifiers {
+  // Cycle 1 = baseline, each subsequent cycle adds variation
+  const t = Math.min((cycleNumber - 1) / 5, 1.0); // 0→1 over 5 cycles
+
+  return {
+    elevationScaleMultiplier: 1.0 + t * 0.3,    // terrain becomes more varied
+    detailScaleMultiplier: 1.0 + t * 0.2,        // more detail features
+    resourceDensityMultiplier: 1.0 + t * 0.15,   // slightly more resources
+    creatureSpawnMultiplier: 1.0 + t * 0.25,     // more creatures
+    escalationRateMultiplier: 1.0 + t * 0.2,     // faster escalation
+  };
+}
+
+// ─── Trace Queries ───────────────────────────────────────────────
+
+/**
+ * Get all traces from the current and previous cycle for a given biome.
+ * Used by world generation to place ruins/markers.
+ */
+export function getTracesForBiome(
+  cycle: GreatCycleState,
+  biomeId: string,
+): RunTrace[] {
+  const currentBiome = cycle.currentCycleTraces.filter(t => t.biomeId === biomeId);
+  const previousBiome = cycle.previousCycleTraces.filter(t => t.biomeId === biomeId);
+  return [...currentBiome, ...previousBiome];
+}
+
+/**
+ * Get traces that left death markers (for ruin placement).
+ * Returns traces with valid death positions.
+ */
+export function getDeathTraces(traces: RunTrace[]): RunTrace[] {
+  return traces.filter(t => t.deathPosition !== null);
+}
+
+/**
+ * Check if the current run is the last in the cycle (7th).
+ */
+export function isLastRunInCycle(cycle: GreatCycleState): boolean {
+  return cycle.runInCycle >= RUNS_PER_CYCLE;
+}
+
+/**
+ * Get a human-readable cycle summary for display.
+ */
+export function getCycleSummary(cycle: GreatCycleState): {
+  cycleNumber: number;
+  runInCycle: number;
+  totalRuns: number;
+  theme: CycleTheme;
+  isLastRun: boolean;
+} {
+  return {
+    cycleNumber: cycle.cycleNumber,
+    runInCycle: cycle.runInCycle,
+    totalRuns: RUNS_PER_CYCLE,
+    theme: cycle.theme,
+    isLastRun: isLastRunInCycle(cycle),
+  };
+}

src/run/escalation.ts

@@ -0,0 +1,48 @@
+/**
+ * Escalation Effects — how rising entropy changes the game world.
+ *
+ * GDD spec:
+ * "Entropy grows. Temperature fluctuates harder, chemical reactions become
+ *  more unstable, creatures more aggressive, NPCs more paranoid."
+ *
+ * Escalation (0.0 → 1.0) modifies:
+ * - Creature speed, aggro range, attack damage
+ * - Reaction instability (chance of unexpected side effects)
+ * - Environmental damage (toxic atmosphere)
+ */
+
+/** Multipliers and modifiers based on escalation level */
+export interface EscalationEffects {
+  /** Creature movement speed multiplier (1.0 → 1.5) */
+  creatureSpeedMultiplier: number;
+  /** Creature aggro detection range multiplier (1.0 → 1.8) */
+  creatureAggroRange: number;
+  /** Creature attack damage multiplier (1.0 → 1.6) */
+  creatureAttackMultiplier: number;
+  /** Reaction instability: chance 0–0.3 of unexpected side effects */
+  reactionInstability: number;
+  /** Environmental damage per second at current escalation */
+  environmentalDamage: number;
+}
+
+/**
+ * Calculate escalation effects from escalation level (0.0–1.0).
+ * All effects scale linearly from neutral to maximum.
+ */
+export function getEscalationEffects(escalation: number): EscalationEffects {
+  // Clamp to [0, 1]
+  const t = Math.max(0, Math.min(1, escalation));
+
+  return {
+    creatureSpeedMultiplier: lerp(1.0, 1.5, t),
+    creatureAggroRange: lerp(1.0, 1.8, t),
+    creatureAttackMultiplier: lerp(1.0, 1.6, t),
+    reactionInstability: lerp(0, 0.3, t),
+    environmentalDamage: t > 0.6 ? lerp(0, 0.5, (t - 0.6) / 0.4) : 0,
+  };
+}
+
+/** Linear interpolation */
+function lerp(a: number, b: number, t: number): number {
+  return a + (b - a) * t;
+}

src/run/meta.ts

@@ -0,0 +1,179 @@
+/**
+ * Meta-Progression — persists between runs.
+ *
+ * Manages the Codex (permanent knowledge), spores (currency),
+ * unlocked schools, run history, and school unlock system.
+ */
+
+import type { MetaState, CodexEntry, RunSummary, SchoolData, ResolvedSchoolBonuses } from './types';
+import type { RunState } from './types';
+import { DEFAULT_SCHOOL_BONUSES } from './types';
+import { calculateSpores, countDiscoveries } from './state';
+import { createGreatCycleState, recordRunAndAdvanceCycle } from './cycle';
+import schoolsData from '../data/schools.json';
+
+/** Create a fresh meta state (first time playing) */
+export function createMetaState(): MetaState {
+  return {
+    spores: 0,
+    codex: [],
+    totalRuns: 0,
+    totalDeaths: 0,
+    unlockedSchools: ['alchemist'],
+    bestRunTime: 0,
+    bestRunDiscoveries: 0,
+    runHistory: [],
+    mycelium: { nodes: [], edges: [], totalDeposits: 0, totalExtractions: 0 },
+    greatCycle: createGreatCycleState(),
+  };
+}
+
+/**
+ * Apply run results to meta state after a run ends (death or completion).
+ * Returns true if a Great Renewal was triggered.
+ */
+export function applyRunResults(meta: MetaState, run: RunState): boolean {
+  // 1. Calculate and add spores
+  const sporesEarned = calculateSpores(run);
+  meta.spores += sporesEarned;
+
+  // 2. Add new codex entries (skip duplicates)
+  const existingIds = new Set(meta.codex.map(e => `${e.type}:${e.id}`));
+
+  for (const elemId of run.discoveries.elements) {
+    const key = `element:${elemId}`;
+    if (!existingIds.has(key)) {
+      meta.codex.push({ id: elemId, type: 'element', discoveredOnRun: run.runId });
+    }
+  }
+  for (const reactionId of run.discoveries.reactions) {
+    const key = `reaction:${reactionId}`;
+    if (!existingIds.has(key)) {
+      meta.codex.push({ id: reactionId, type: 'reaction', discoveredOnRun: run.runId });
+    }
+  }
+  for (const compoundId of run.discoveries.compounds) {
+    const key = `compound:${compoundId}`;
+    if (!existingIds.has(key)) {
+      meta.codex.push({ id: compoundId, type: 'compound', discoveredOnRun: run.runId });
+    }
+  }
+  for (const creatureId of run.discoveries.creatures) {
+    const key = `creature:${creatureId}`;
+    if (!existingIds.has(key)) {
+      meta.codex.push({ id: creatureId, type: 'creature', discoveredOnRun: run.runId });
+    }
+  }
+
+  // 3. Update stats
+  meta.totalRuns += 1;
+  meta.totalDeaths += 1; // every run ends in death (for now)
+
+  const discoveryCount = countDiscoveries(run);
+  if (run.elapsed > meta.bestRunTime) {
+    meta.bestRunTime = run.elapsed;
+  }
+  if (discoveryCount > meta.bestRunDiscoveries) {
+    meta.bestRunDiscoveries = discoveryCount;
+  }
+
+  // 4. Add to run history (with cycle info)
+  const summary: RunSummary = {
+    runId: run.runId,
+    schoolId: run.schoolId,
+    duration: run.elapsed,
+    phase: run.phase,
+    discoveries: discoveryCount,
+    sporesEarned,
+    crisisResolved: run.crisisResolved,
+    biomeId: run.biomeId,
+    cycleNumber: meta.greatCycle.cycleNumber,
+  };
+  meta.runHistory.push(summary);
+
+  // 5. Record run trace and advance the great cycle
+  const isRenewal = recordRunAndAdvanceCycle(meta, run);
+
+  // 6. Check for school unlocks after updating codex and stats
+  checkSchoolUnlocks(meta);
+
+  return isRenewal;
+}
+
+/** Check if a school is unlocked */
+export function isSchoolUnlocked(meta: MetaState, schoolId: string): boolean {
+  return meta.unlockedSchools.includes(schoolId);
+}
+
+/** Get codex entries filtered by type */
+export function getCodexEntries(
+  meta: MetaState,
+  type: CodexEntry['type'],
+): CodexEntry[] {
+  return meta.codex.filter(e => e.type === type);
+}
+
+/** Get total codex entry count */
+export function getCodexCount(meta: MetaState): number {
+  return meta.codex.length;
+}
+
+// ─── School Unlock System ────────────────────────────────────────
+
+const schools = schoolsData as unknown as SchoolData[];
+
+/**
+ * Check all school unlock conditions against current meta state.
+ * Newly unlocked schools are added to meta.unlockedSchools.
+ */
+export function checkSchoolUnlocks(meta: MetaState): void {
+  for (const school of schools) {
+    // Skip already unlocked
+    if (meta.unlockedSchools.includes(school.id)) continue;
+    // Schools without condition are always available (e.g., alchemist)
+    if (!school.unlockCondition) {
+      meta.unlockedSchools.push(school.id);
+      continue;
+    }
+
+    const condition = school.unlockCondition;
+    let met = false;
+
+    switch (condition.type) {
+      case 'elements_discovered': {
+        const count = meta.codex.filter(e => e.type === 'element').length;
+        met = count >= condition.threshold;
+        break;
+      }
+      case 'creatures_discovered': {
+        const count = meta.codex.filter(e => e.type === 'creature').length;
+        met = count >= condition.threshold;
+        break;
+      }
+      case 'runs_completed': {
+        met = meta.totalRuns >= condition.threshold;
+        break;
+      }
+    }
+
+    if (met) {
+      meta.unlockedSchools.push(school.id);
+    }
+  }
+}
+
+// ─── School Bonuses ──────────────────────────────────────────────
+
+/**
+ * Resolve school bonuses into a complete multiplier set.
+ * Unknown school ID returns all-default (1.0) bonuses.
+ */
+export function getSchoolBonuses(schoolId: string): ResolvedSchoolBonuses {
+  const school = schools.find(s => s.id === schoolId);
+  if (!school) return { ...DEFAULT_SCHOOL_BONUSES };
+
+  return {
+    ...DEFAULT_SCHOOL_BONUSES,
+    ...school.bonuses,
+  };
+}

src/run/persistence.ts

@@ -0,0 +1,133 @@
+/**
+ * Persistence — IndexedDB storage for meta-progression.
+ *
+ * Saves/loads MetaState between browser sessions.
+ * Uses a simple key-value pattern with a single object store.
+ */
+
+import type { MetaState, CodexEntry, RunSummary, MyceliumGraphData, GreatCycleState } from './types';
+import { createMetaState } from './meta';
+import { createGreatCycleState } from './cycle';
+
+const DB_NAME = 'synthesis-meta';
+const DB_VERSION = 1;
+const STORE_NAME = 'meta';
+const META_KEY = 'metaState';
+
+/** Serializable version of MetaState (no Sets, plain objects) */
+interface SerializedMetaState {
+  spores: number;
+  codex: CodexEntry[];
+  totalRuns: number;
+  totalDeaths: number;
+  unlockedSchools: string[];
+  bestRunTime: number;
+  bestRunDiscoveries: number;
+  runHistory: RunSummary[];
+  mycelium?: MyceliumGraphData;
+  greatCycle?: GreatCycleState;
+}
+
+/** Open (or create) the IndexedDB database */
+function openDB(): Promise<IDBDatabase> {
+  return new Promise((resolve, reject) => {
+    const request = indexedDB.open(DB_NAME, DB_VERSION);
+
+    request.onupgradeneeded = () => {
+      const db = request.result;
+      if (!db.objectStoreNames.contains(STORE_NAME)) {
+        db.createObjectStore(STORE_NAME);
+      }
+    };
+
+    request.onsuccess = () => resolve(request.result);
+    request.onerror = () => reject(request.error);
+  });
+}
+
+/** Serialize MetaState to plain JSON-safe object */
+function serialize(meta: MetaState): SerializedMetaState {
+  return {
+    spores: meta.spores,
+    codex: [...meta.codex],
+    totalRuns: meta.totalRuns,
+    totalDeaths: meta.totalDeaths,
+    unlockedSchools: [...meta.unlockedSchools],
+    bestRunTime: meta.bestRunTime,
+    bestRunDiscoveries: meta.bestRunDiscoveries,
+    runHistory: [...meta.runHistory],
+    mycelium: meta.mycelium,
+    greatCycle: meta.greatCycle,
+  };
+}
+
+/** Default empty mycelium graph */
+const EMPTY_MYCELIUM: MyceliumGraphData = {
+  nodes: [], edges: [], totalDeposits: 0, totalExtractions: 0,
+};
+
+/** Deserialize from plain object back to MetaState */
+function deserialize(data: SerializedMetaState): MetaState {
+  return {
+    spores: data.spores ?? 0,
+    codex: data.codex ?? [],
+    totalRuns: data.totalRuns ?? 0,
+    totalDeaths: data.totalDeaths ?? 0,
+    unlockedSchools: data.unlockedSchools ?? ['alchemist'],
+    bestRunTime: data.bestRunTime ?? 0,
+    bestRunDiscoveries: data.bestRunDiscoveries ?? 0,
+    runHistory: data.runHistory ?? [],
+    mycelium: data.mycelium ?? EMPTY_MYCELIUM,
+    greatCycle: data.greatCycle ?? createGreatCycleState(),
+  };
+}
+
+/** Save meta state to IndexedDB */
+export async function saveMetaState(meta: MetaState): Promise<void> {
+  const db = await openDB();
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction(STORE_NAME, 'readwrite');
+    const store = tx.objectStore(STORE_NAME);
+    const request = store.put(serialize(meta), META_KEY);
+
+    request.onsuccess = () => resolve();
+    request.onerror = () => reject(request.error);
+    tx.oncomplete = () => db.close();
+  });
+}
+
+/** Load meta state from IndexedDB. Returns fresh state if nothing saved. */
+export async function loadMetaState(): Promise<MetaState> {
+  try {
+    const db = await openDB();
+    return new Promise((resolve, reject) => {
+      const tx = db.transaction(STORE_NAME, 'readonly');
+      const store = tx.objectStore(STORE_NAME);
+      const request = store.get(META_KEY);
+
+      request.onsuccess = () => {
+        const data = request.result as SerializedMetaState | undefined;
+        resolve(data ? deserialize(data) : createMetaState());
+      };
+      request.onerror = () => reject(request.error);
+      tx.oncomplete = () => db.close();
+    });
+  } catch {
+    // If IndexedDB is unavailable, return fresh state
+    return createMetaState();
+  }
+}
+
+/** Clear all saved data (for debug/reset) */
+export async function clearMetaState(): Promise<void> {
+  const db = await openDB();
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction(STORE_NAME, 'readwrite');
+    const store = tx.objectStore(STORE_NAME);
+    const request = store.delete(META_KEY);
+
+    request.onsuccess = () => resolve();
+    request.onerror = () => reject(request.error);
+    tx.oncomplete = () => db.close();
+  });
+}

src/run/state.ts

@@ -0,0 +1,101 @@
+/**
+ * Run State Management — creates and updates the state of a single run.
+ *
+ * A "run" is one cycle: Awakening → Exploration → Escalation → Crisis → Resolution.
+ * Each run tracks discoveries, escalation level, and crisis status.
+ */
+
+import {
+  type RunState,
+  type RunDiscoveries,
+  RunPhase,
+  ESCALATION_RATE,
+  SPORE_REWARDS,
+} from './types';
+
+/** Create a fresh run state for a new run */
+export function createRunState(
+  runId: number,
+  schoolId: string,
+  biomeId: string = 'catalytic-wastes',
+  worldSeed: number = Date.now(),
+): RunState {
+  return {
+    runId,
+    schoolId,
+    biomeId,
+    phase: RunPhase.Awakening,
+    phaseTimer: 0,
+    elapsed: 0,
+    escalation: 0,
+    crisisActive: false,
+    crisisResolved: false,
+    discoveries: {
+      elements: new Set<string>(),
+      reactions: new Set<string>(),
+      compounds: new Set<string>(),
+      creatures: new Set<string>(),
+    },
+    alive: true,
+    worldSeed,
+    deathPosition: null,
+  };
+}
+
+/** Advance to the next phase. Does nothing if already at Resolution. */
+export function advancePhase(state: RunState): void {
+  if (state.phase < RunPhase.Resolution) {
+    state.phase = (state.phase + 1) as RunPhase;
+    state.phaseTimer = 0;
+  }
+}
+
+/** Update escalation level based on elapsed delta (ms). Only active during Escalation and Crisis. */
+export function updateEscalation(state: RunState, deltaMs: number): void {
+  if (state.phase < RunPhase.Escalation) return;
+  if (state.phase > RunPhase.Crisis) return;
+
+  const deltaSec = deltaMs / 1000;
+  state.escalation = Math.min(1.0, state.escalation + ESCALATION_RATE * deltaSec);
+}
+
+/** Discovery type names used in API (singular) */
+export type DiscoveryType = 'element' | 'reaction' | 'compound' | 'creature';
+
+/** Map singular type to plural key in RunDiscoveries */
+const DISCOVERY_KEY: Record<DiscoveryType, keyof RunDiscoveries> = {
+  element: 'elements',
+  reaction: 'reactions',
+  compound: 'compounds',
+  creature: 'creatures',
+};
+
+/** Record a discovery during the current run */
+export function recordDiscovery(
+  state: RunState,
+  type: DiscoveryType,
+  id: string,
+): void {
+  state.discoveries[DISCOVERY_KEY[type]].add(id);
+}
+
+/** Count total unique discoveries in a run */
+export function countDiscoveries(state: RunState): number {
+  return (
+    state.discoveries.elements.size +
+    state.discoveries.reactions.size +
+    state.discoveries.compounds.size +
+    state.discoveries.creatures.size
+  );
+}
+
+/** Calculate spores earned from a run */
+export function calculateSpores(state: RunState): number {
+  let total = 0;
+  total += state.discoveries.elements.size * SPORE_REWARDS.element;
+  total += state.discoveries.reactions.size * SPORE_REWARDS.reaction;
+  total += state.discoveries.compounds.size * SPORE_REWARDS.compound;
+  total += state.discoveries.creatures.size * SPORE_REWARDS.creature;
+  if (state.crisisResolved) total += SPORE_REWARDS.crisisResolved;
+  return total;
+}

src/run/types.ts

@@ -0,0 +1,370 @@
+/**
+ * Run Cycle Types — schools, run phases, meta-progression
+ *
+ * Defines the structure of a single run (birth → death → rebirth)
+ * and the persistent meta-progression between runs.
+ */
+
+// ─── Schools ─────────────────────────────────────────────────────
+
+export interface SchoolData {
+  id: string;
+  name: string;
+  nameRu: string;
+  description: string;
+  descriptionRu: string;
+  /** Starting element symbols (looked up in element registry) */
+  startingElements: string[];
+  /** Quantity of each starting element */
+  startingQuantities: Record<string, number>;
+  /** Scientific principle the school teaches */
+  principle: string;
+  principleRu: string;
+  /** Play style description */
+  playstyle: string;
+  playstyleRu: string;
+  /** Hex color for UI representation */
+  color: string;
+  /** Passive gameplay bonuses from this school's principle */
+  bonuses: Record<string, number>;
+  /** Condition to unlock this school (absent = always unlocked) */
+  unlockCondition?: SchoolUnlockCondition;
+}
+
+/** Condition that must be met to unlock a school */
+export interface SchoolUnlockCondition {
+  /** What metric to check */
+  type: 'elements_discovered' | 'creatures_discovered' | 'runs_completed';
+  /** How many needed */
+  threshold: number;
+  /** Hint text (English) shown when locked */
+  hint: string;
+  /** Hint text (Russian) shown when locked */
+  hintRu: string;
+}
+
+/** Resolved school bonuses with all multipliers filled in (defaults = 1.0) */
+export interface ResolvedSchoolBonuses {
+  /** Projectile damage multiplier */
+  projectileDamage: number;
+  /** Player movement speed multiplier */
+  movementSpeed: number;
+  /** Creature aggro/flee range multiplier (< 1 = less aggro) */
+  creatureAggroRange: number;
+  /** Reaction efficiency multiplier */
+  reactionEfficiency: number;
+}
+
+/** Default bonuses (no school effect) */
+export const DEFAULT_SCHOOL_BONUSES: ResolvedSchoolBonuses = {
+  projectileDamage: 1.0,
+  movementSpeed: 1.0,
+  creatureAggroRange: 1.0,
+  reactionEfficiency: 1.0,
+};
+
+// ─── Run Phases ──────────────────────────────────────────────────
+
+/** Phases of a single run in order */
+export enum RunPhase {
+  Awakening = 0,
+  Exploration = 1,
+  Escalation = 2,
+  Crisis = 3,
+  Resolution = 4,
+}
+
+/** Human-readable names for RunPhase */
+export const RUN_PHASE_NAMES: Record<RunPhase, string> = {
+  [RunPhase.Awakening]: 'Awakening',
+  [RunPhase.Exploration]: 'Exploration',
+  [RunPhase.Escalation]: 'Escalation',
+  [RunPhase.Crisis]: 'Crisis',
+  [RunPhase.Resolution]: 'Resolution',
+};
+
+export const RUN_PHASE_NAMES_RU: Record<RunPhase, string> = {
+  [RunPhase.Awakening]: 'Пробуждение',
+  [RunPhase.Exploration]: 'Исследование',
+  [RunPhase.Escalation]: 'Эскалация',
+  [RunPhase.Crisis]: 'Кризис',
+  [RunPhase.Resolution]: 'Развязка',
+};
+
+// ─── Crisis Types ────────────────────────────────────────────────
+
+export type CrisisType = 'chemical-plague';
+
+export interface CrisisConfig {
+  type: CrisisType;
+  name: string;
+  nameRu: string;
+  description: string;
+  descriptionRu: string;
+  /** Escalation threshold (0-1) at which crisis triggers */
+  triggerThreshold: number;
+  /** Compound that neutralizes the crisis */
+  neutralizer: string;
+  /** Amount needed to neutralize */
+  neutralizeAmount: number;
+}
+
+// ─── Run State ───────────────────────────────────────────────────
+
+/** State of the current run */
+export interface RunState {
+  /** Unique run identifier */
+  runId: number;
+  /** Selected school id */
+  schoolId: string;
+  /** Biome being explored this run */
+  biomeId: string;
+  /** Current phase */
+  phase: RunPhase;
+  /** Time spent in current phase (ms) */
+  phaseTimer: number;
+  /** Total run elapsed time (ms) */
+  elapsed: number;
+  /** Escalation level 0.0 – 1.0 */
+  escalation: number;
+  /** Whether crisis has been triggered */
+  crisisActive: boolean;
+  /** Whether crisis has been resolved */
+  crisisResolved: boolean;
+  /** Discoveries made this run */
+  discoveries: RunDiscoveries;
+  /** Whether the player is alive */
+  alive: boolean;
+  /** World seed for this run */
+  worldSeed: number;
+  /** Player death position in tile coords (set on death) */
+  deathPosition: { tileX: number; tileY: number } | null;
+}
+
+export interface RunDiscoveries {
+  elements: Set<string>;
+  reactions: Set<string>;
+  compounds: Set<string>;
+  creatures: Set<string>;
+}
+
+// ─── Meta-Progression (persists between runs) ────────────────────
+
+export interface CodexEntry {
+  id: string;
+  type: 'element' | 'reaction' | 'compound' | 'creature' | 'boss';
+  discoveredOnRun: number;
+}
+
+export interface MetaState {
+  /** Total spores earned across all runs */
+  spores: number;
+  /** All codex entries (permanent knowledge) */
+  codex: CodexEntry[];
+  /** Total runs completed */
+  totalRuns: number;
+  /** Total deaths */
+  totalDeaths: number;
+  /** Unlocked school ids */
+  unlockedSchools: string[];
+  /** Best run statistics */
+  bestRunTime: number;
+  bestRunDiscoveries: number;
+  /** Run history summaries */
+  runHistory: RunSummary[];
+  /** Mycelium knowledge graph (persistent between runs) */
+  mycelium: MyceliumGraphData;
+  /** Great cycle state (7-run macro cycles) */
+  greatCycle: GreatCycleState;
+}
+
+/** Serializable Mycelium graph data (stored in MetaState) */
+export interface MyceliumGraphData {
+  /** Knowledge nodes */
+  nodes: MyceliumNodeData[];
+  /** Connections between nodes */
+  edges: MyceliumEdgeData[];
+  /** Total deposits across all runs */
+  totalDeposits: number;
+  /** Total extractions across all runs */
+  totalExtractions: number;
+}
+
+/** A knowledge node in the persistent Mycelium graph */
+export interface MyceliumNodeData {
+  /** Unique node ID (format: "type:id", e.g. "element:Na") */
+  id: string;
+  /** Knowledge category */
+  type: 'element' | 'reaction' | 'compound' | 'creature';
+  /** Reference to the specific knowledge item */
+  knowledgeId: string;
+  /** Run on which this was first deposited */
+  depositedOnRun: number;
+  /** Knowledge strength 0–1 (increases with repeated deposits) */
+  strength: number;
+}
+
+/** An edge connecting two knowledge nodes in the Mycelium */
+export interface MyceliumEdgeData {
+  /** Source node ID */
+  from: string;
+  /** Target node ID */
+  to: string;
+  /** Connection strength 0–1 */
+  weight: number;
+}
+
+export interface RunSummary {
+  runId: number;
+  schoolId: string;
+  duration: number;
+  phase: RunPhase;
+  discoveries: number;
+  sporesEarned: number;
+  crisisResolved: boolean;
+  /** Biome explored (added Phase 11) */
+  biomeId?: string;
+  /** Great cycle number when this run occurred */
+  cycleNumber?: number;
+}
+
+// ─── Body Composition (for death animation) ──────────────────────
+
+/** Real elemental composition of the human body (simplified) */
+export const BODY_COMPOSITION: { symbol: string; fraction: number }[] = [
+  { symbol: 'O', fraction: 0.65 },
+  { symbol: 'C', fraction: 0.18 },
+  { symbol: 'H', fraction: 0.10 },
+  { symbol: 'N', fraction: 0.03 },
+  { symbol: 'Ca', fraction: 0.015 },
+  { symbol: 'P', fraction: 0.01 },
+  { symbol: 'S', fraction: 0.003 },
+  { symbol: 'Na', fraction: 0.002 },
+  { symbol: 'K', fraction: 0.002 },
+  { symbol: 'Fe', fraction: 0.001 },
+];
+
+// ─── Great Cycle (every 7 runs) ──────────────────────────────────
+
+/** Narrative themes for each great cycle (GDD Section IV) */
+export type CycleTheme =
+  | 'awakening'   // Cycle 1 (runs 1-7): learning the world
+  | 'doubt'       // Cycle 2 (runs 8-14): finding traces of past adepts
+  | 'realization' // Cycle 3 (runs 15-21): understanding the nature of cycles
+  | 'attempt'     // Cycle 4 (runs 22-28): first attempts to transcend
+  | 'acceptance'  // Cycle 5 (runs 29-35): cycle is not a prison
+  | 'synthesis';  // Cycle 6+ (runs 36+): unifying all knowledge
+
+/** Human-readable names for CycleTheme */
+export const CYCLE_THEME_NAMES: Record<CycleTheme, string> = {
+  awakening: 'Awakening',
+  doubt: 'Doubt',
+  realization: 'Realization',
+  attempt: 'Attempt',
+  acceptance: 'Acceptance',
+  synthesis: 'Synthesis',
+};
+
+export const CYCLE_THEME_NAMES_RU: Record<CycleTheme, string> = {
+  awakening: 'Пробуждение',
+  doubt: 'Сомнение',
+  realization: 'Осознание',
+  attempt: 'Попытка',
+  acceptance: 'Принятие',
+  synthesis: 'Синтез',
+};
+
+/** Ordered themes by cycle number (0-indexed, cycles beyond 6 repeat 'synthesis') */
+export const CYCLE_THEMES: CycleTheme[] = [
+  'awakening',
+  'doubt',
+  'realization',
+  'attempt',
+  'acceptance',
+  'synthesis',
+];
+
+/** A trace left by a completed run within a great cycle */
+export interface RunTrace {
+  /** Run ID this trace belongs to */
+  runId: number;
+  /** Position within the great cycle (1-7) */
+  runInCycle: number;
+  /** School used this run */
+  schoolId: string;
+  /** Biome explored */
+  biomeId: string;
+  /** Death location (tile coords), null if run completed via boss victory */
+  deathPosition: { tileX: number; tileY: number } | null;
+  /** Phase reached when run ended */
+  phaseReached: RunPhase;
+  /** Was the crisis resolved? */
+  crisisResolved: boolean;
+  /** Number of unique discoveries */
+  discoveryCount: number;
+  /** Key element discoveries (up to 5 symbols for trace markers) */
+  keyElements: string[];
+  /** Duration of the run in ms */
+  duration: number;
+  /** World seed used for this run */
+  worldSeed: number;
+}
+
+/** Persistent great cycle state (stored in MetaState) */
+export interface GreatCycleState {
+  /** Current great cycle number (1-based) */
+  cycleNumber: number;
+  /** Current run within the cycle (1-7, resets on renewal) */
+  runInCycle: number;
+  /** Current cycle's theme */
+  theme: CycleTheme;
+  /** Traces from runs in the CURRENT cycle (cleared on renewal) */
+  currentCycleTraces: RunTrace[];
+  /** Traces from the PREVIOUS cycle (for cross-cycle references) */
+  previousCycleTraces: RunTrace[];
+  /** Total great renewals completed */
+  renewalsCompleted: number;
+  /** Mycelium maturation level (increases each renewal) */
+  myceliumMaturation: number;
+}
+
+/** Number of runs per great cycle */
+export const RUNS_PER_CYCLE = 7;
+
+/** World generation modifiers based on cycle number */
+export interface CycleWorldModifiers {
+  /** Elevation noise scale multiplier (world shape variation) */
+  elevationScaleMultiplier: number;
+  /** Detail noise scale multiplier */
+  detailScaleMultiplier: number;
+  /** Resource density multiplier */
+  resourceDensityMultiplier: number;
+  /** Creature spawn rate multiplier */
+  creatureSpawnMultiplier: number;
+  /** Escalation rate multiplier (difficulty) */
+  escalationRateMultiplier: number;
+}
+
+// ─── Constants ───────────────────────────────────────────────────
+
+/** Phase durations in ms (approximate, can be adjusted) */
+export const PHASE_DURATIONS: Record<RunPhase, number> = {
+  [RunPhase.Awakening]: 0,         // ends when player leaves Cradle
+  [RunPhase.Exploration]: 180_000, // 3 minutes
+  [RunPhase.Escalation]: 120_000,  // 2 minutes
+  [RunPhase.Crisis]: 0,            // ends when resolved or player dies
+  [RunPhase.Resolution]: 60_000,   // 1 minute
+};
+
+/** Escalation growth rate per second (0→1 over Escalation phase) */
+export const ESCALATION_RATE = 0.005;
+
+/** Spores awarded per discovery type */
+export const SPORE_REWARDS = {
+  element: 5,
+  reaction: 10,
+  compound: 8,
+  creature: 15,
+  crisisResolved: 50,
+  runCompleted: 20,
+};

src/scenes/BootScene.ts

@@ -1,4 +1,6 @@
 import Phaser from 'phaser';
+import { loadMetaState } from '../run/persistence';
+import { createMetaState } from '../run/meta';
 
 export class BootScene extends Phaser.Scene {
   constructor() {
@@ -30,7 +32,7 @@ export class BootScene extends Phaser.Scene {
 
     // Version
     this.add
-      .text(cx, cy + 80, 'v0.2.0 — Phase 2: ECS Foundation', {
+      .text(cx, cy + 80, 'v0.6.0 — Phase 6: Run Cycle', {
         fontSize: '12px',
         color: '#333333',
         fontFamily: 'monospace',
@@ -56,7 +58,15 @@ export class BootScene extends Phaser.Scene {
     });
 
     this.input.once('pointerdown', () => {
-      this.scene.start('GameScene');
+      // Load meta-progression from IndexedDB, then go to Cradle
+      loadMetaState()
+        .then(meta => {
+          this.scene.start('CradleScene', { meta });
+        })
+        .catch(() => {
+          // Fallback to fresh meta if persistence fails
+          this.scene.start('CradleScene', { meta: createMetaState() });
+        });
     });
   }
 }

src/scenes/BossArenaScene.ts

@@ -0,0 +1,772 @@
+/**
+ * BossArenaScene — Archon boss fight in a circular arena
+ *
+ * Features:
+ * - Circular arena tilemap with hazards
+ * - Boss entity with cyclical phase AI
+ * - 3 victory paths (chemical, direct, catalytic)
+ * - Boss health bar and phase indicator
+ * - Reward on victory → transition to CradleScene
+ * - Death → normal DeathScene flow
+ */
+
+import Phaser from 'phaser';
+import { createGameWorld, updateTime, type GameWorld } from '../ecs/world';
+import { Health, Position, Boss as BossComponent, Velocity } from '../ecs/components';
+import { movementSystem } from '../ecs/systems/movement';
+import { healthSystem } from '../ecs/systems/health';
+import { removeGameEntity } from '../ecs/factory';
+import { PhaserBridge } from '../ecs/bridge';
+import biomeDataArray from '../data/biomes.json';
+import bossDataArray from '../data/bosses.json';
+import type { BiomeData } from '../world/types';
+import { createWorldTilemap } from '../world/tilemap';
+import { buildWalkableSet } from '../player/collision';
+import { createPlayerEntity } from '../player/factory';
+import { Inventory } from '../player/inventory';
+import {
+  launchProjectile,
+  projectileSystem,
+  type ProjectileData,
+} from '../player/projectile';
+import { playerInputSystem } from '../player/input';
+import { tileCollisionSystem } from '../player/collision';
+import { QuickSlots } from '../player/quickslots';
+import type { InputState } from '../player/types';
+
+// Boss imports
+import type { BossData, BossState, BossPhaseEvent } from '../boss/types';
+import { BossPhase, BOSS_PHASE_NAMES_RU } from '../boss/types';
+import { createBossState, updateBossPhase, getEffectiveArmor, isVulnerable } from '../boss/ai';
+import { applyBossDamage, isBossDefeated } from '../boss/victory';
+import { generateArena, buildArenaWalkableSet } from '../boss/arena';
+import { createBossEntity } from '../boss/factory';
+import { calculateBossReward, applyBossReward } from '../boss/reward';
+
+// Run cycle imports
+import type { MetaState, RunState } from '../run/types';
+import { query } from 'bitecs';
+import { Projectile } from '../ecs/components';
+
+// UI zoom compensation
+import { fixToScreen } from '../ui/screen-fix';
+
+/** Data passed from GameScene to BossArenaScene */
+interface BossArenaInitData {
+  meta: MetaState;
+  runState: RunState;
+  inventoryItems: { id: string; count: number }[];
+  quickSlotItems: (string | null)[];
+  activeSlot: number;
+  playerHealth: number;
+  playerMaxHealth: number;
+}
+
+export class BossArenaScene extends Phaser.Scene {
+  private gameWorld!: GameWorld;
+  private bridge!: PhaserBridge;
+
+  // Player
+  private playerEid!: number;
+  private inventory!: Inventory;
+  private quickSlots!: QuickSlots;
+  private walkableSet!: Set<number>;
+  private worldGrid!: number[][];
+  private tileSize!: number;
+  private projectileData!: Map<number, ProjectileData>;
+  private keys!: {
+    W: Phaser.Input.Keyboard.Key;
+    A: Phaser.Input.Keyboard.Key;
+    S: Phaser.Input.Keyboard.Key;
+    D: Phaser.Input.Keyboard.Key;
+    E: Phaser.Input.Keyboard.Key;
+    F: Phaser.Input.Keyboard.Key;
+    ONE: Phaser.Input.Keyboard.Key;
+    TWO: Phaser.Input.Keyboard.Key;
+    THREE: Phaser.Input.Keyboard.Key;
+    FOUR: Phaser.Input.Keyboard.Key;
+  };
+
+  // Boss
+  private bossEid!: number;
+  private bossData!: BossData;
+  private bossState!: BossState;
+  private bossProjectiles: number[] = [];
+  private bossAttackTimer = 0;
+
+  // Run state
+  private meta!: MetaState;
+  private runState!: RunState;
+  private playerDead = false;
+  private victoryAchieved = false;
+
+  // UI elements
+  private bossHealthBar!: Phaser.GameObjects.Graphics;
+  private bossHealthText!: Phaser.GameObjects.Text;
+  private phaseText!: Phaser.GameObjects.Text;
+  private feedbackText!: Phaser.GameObjects.Text;
+  private feedbackTimer = 0;
+  private bossGlowGraphics!: Phaser.GameObjects.Graphics;
+
+  // Input debounce
+  private wasFDown = false;
+
+  constructor() {
+    super({ key: 'BossArenaScene' });
+  }
+
+  init(data: BossArenaInitData): void {
+    this.meta = data.meta;
+    this.runState = data.runState;
+    this.playerDead = false;
+    this.victoryAchieved = false;
+    this.bossProjectiles = [];
+    this.bossAttackTimer = 0;
+
+    // Restore inventory
+    this.inventory = new Inventory(500, 20);
+    for (const item of data.inventoryItems) {
+      for (let i = 0; i < item.count; i++) {
+        this.inventory.addItem(item.id);
+      }
+    }
+
+    // Restore quick slots
+    this.quickSlots = new QuickSlots();
+    for (let i = 0; i < data.quickSlotItems.length; i++) {
+      this.quickSlots.assign(i, data.quickSlotItems[i]);
+    }
+    this.quickSlots.setActive(data.activeSlot);
+  }
+
+  create(): void {
+    const biome = biomeDataArray[0] as BiomeData;
+    this.bossData = bossDataArray[0] as BossData;
+    this.tileSize = biome.tileSize;
+
+    // 1. Initialize ECS
+    this.gameWorld = createGameWorld();
+    this.bridge = new PhaserBridge(this);
+    this.projectileData = new Map();
+
+    // 2. Generate arena
+    const arena = generateArena(this.bossData, biome);
+    this.worldGrid = arena.grid;
+    this.walkableSet = buildArenaWalkableSet();
+
+    // 3. Create tilemap (reuse world tilemap system)
+    const arenaWorldData = {
+      grid: arena.grid,
+      biome: biome,
+      seed: 0,
+    };
+    createWorldTilemap(this, arenaWorldData);
+
+    // 4. Create player entity at arena entrance
+    this.playerEid = createPlayerEntity(
+      this.gameWorld.world, arena.playerSpawnX, arena.playerSpawnY,
+    );
+
+    // Apply player health from GameScene
+    const initData = this.scene.settings.data as BossArenaInitData;
+    if (initData?.playerHealth !== undefined) {
+      Health.current[this.playerEid] = initData.playerHealth;
+      Health.max[this.playerEid] = initData.playerMaxHealth;
+    }
+
+    // 5. Create boss entity at center
+    this.bossEid = createBossEntity(
+      this.gameWorld.world, this.bossData, arena.bossSpawnX, arena.bossSpawnY,
+    );
+    this.bossState = createBossState(this.bossData);
+
+    // 6. Camera setup
+    const worldPixelW = arena.width * this.tileSize;
+    const worldPixelH = arena.height * this.tileSize;
+    this.cameras.main.setBounds(0, 0, worldPixelW, worldPixelH);
+    this.cameras.main.setZoom(2.0); // Closer zoom for arena
+
+    // Sync bridge to create sprites, then follow player
+    this.bridge.sync(this.gameWorld.world);
+    const playerSprite = this.bridge.getSprite(this.playerEid);
+    if (playerSprite) {
+      playerSprite.setDepth(10);
+      this.cameras.main.startFollow(playerSprite, true, 0.1, 0.1);
+    }
+
+    // 7. Keyboard input
+    const keyboard = this.input.keyboard;
+    if (!keyboard) throw new Error('Keyboard plugin not available');
+    this.keys = {
+      W: keyboard.addKey('W'),
+      A: keyboard.addKey('A'),
+      S: keyboard.addKey('S'),
+      D: keyboard.addKey('D'),
+      E: keyboard.addKey('E'),
+      F: keyboard.addKey('F'),
+      ONE: keyboard.addKey(Phaser.Input.Keyboard.KeyCodes.ONE),
+      TWO: keyboard.addKey(Phaser.Input.Keyboard.KeyCodes.TWO),
+      THREE: keyboard.addKey(Phaser.Input.Keyboard.KeyCodes.THREE),
+      FOUR: keyboard.addKey(Phaser.Input.Keyboard.KeyCodes.FOUR),
+    };
+
+    // 8. Boss glow graphics (world-space)
+    this.bossGlowGraphics = this.add.graphics();
+    this.bossGlowGraphics.setDepth(5);
+
+    // 9. UI elements (screen-space)
+    this.createBossUI();
+
+    // 10. Launch UIScene for player HUD
+    this.scene.launch('UIScene');
+
+    // Entry announcement
+    this.showFeedback('⚔ УРОБОРОС — Архонт Циклов');
+  }
+
+  update(_time: number, delta: number): void {
+    if (this.playerDead || this.victoryAchieved) return;
+
+    // 1. Update world time
+    updateTime(this.gameWorld, delta);
+
+    // 2. Player input
+    const input: InputState = {
+      moveX: (this.keys.D.isDown ? 1 : 0) - (this.keys.A.isDown ? 1 : 0),
+      moveY: (this.keys.S.isDown ? 1 : 0) - (this.keys.W.isDown ? 1 : 0),
+      interact: this.keys.E.isDown,
+    };
+    playerInputSystem(this.gameWorld.world, input);
+
+    // 3. Movement
+    movementSystem(this.gameWorld.world, delta);
+
+    // 4. Tile collision (player)
+    tileCollisionSystem(
+      this.gameWorld.world, delta,
+      this.worldGrid, this.tileSize, this.walkableSet,
+    );
+
+    // 5. Projectile system
+    projectileSystem(
+      this.gameWorld.world, delta,
+      this.worldGrid, this.tileSize, this.walkableSet,
+      this.projectileData,
+    );
+
+    // 6. Quick slots
+    if (this.keys.ONE.isDown) this.quickSlots.setActive(0);
+    if (this.keys.TWO.isDown) this.quickSlots.setActive(1);
+    if (this.keys.THREE.isDown) this.quickSlots.setActive(2);
+    if (this.keys.FOUR.isDown) this.quickSlots.setActive(3);
+
+    // 7. Throw projectile (F key)
+    const isFDown = this.keys.F.isDown;
+    const justPressedF = isFDown && !this.wasFDown;
+    this.wasFDown = isFDown;
+    if (justPressedF) {
+      this.tryLaunchProjectile();
+    }
+
+    // 8. Boss AI phase update
+    const bossEvents = updateBossPhase(this.bossState, this.bossData, delta);
+    this.handleBossEvents(bossEvents, delta);
+
+    // Sync boss ECS component with runtime state
+    BossComponent.phase[this.bossEid] = this.bossState.currentPhase;
+    BossComponent.cycleCount[this.bossEid] = this.bossState.cycleCount;
+
+    // 9. Boss attack behavior
+    this.updateBossAttacks(delta);
+
+    // 10. Check projectile → boss collision
+    this.checkProjectileBossCollision();
+
+    // 11. Health system
+    const dead = healthSystem(this.gameWorld.world);
+    let playerDied = false;
+    for (const eid of dead) {
+      if (eid === this.playerEid) {
+        playerDied = true;
+        continue;
+      }
+      if (eid === this.bossEid) {
+        continue; // Boss death handled by victory system
+      }
+      removeGameEntity(this.gameWorld.world, eid);
+    }
+
+    if (playerDied) {
+      this.onPlayerDeath();
+      return;
+    }
+
+    // 12. Check victory
+    if (isBossDefeated(this.bossState)) {
+      this.onBossDefeated();
+      return;
+    }
+
+    // 13. Render sync
+    this.bridge.sync(this.gameWorld.world);
+
+    // 14. Update boss visuals
+    this.updateBossVisuals(delta);
+
+    // 15. Update UI
+    this.updateBossUI();
+
+    // 16. Feedback text fade
+    if (this.feedbackTimer > 0) {
+      this.feedbackTimer -= delta;
+      if (this.feedbackTimer <= 500) {
+        this.feedbackText.setAlpha(this.feedbackTimer / 500);
+      }
+      if (this.feedbackTimer <= 0) {
+        this.feedbackText.setAlpha(0);
+      }
+    }
+
+    // 17. Push state to registry for UIScene
+    this.registry.set('health', Health.current[this.playerEid] ?? 100);
+    this.registry.set('healthMax', Health.max[this.playerEid] ?? 100);
+    this.registry.set('quickSlots', this.quickSlots.getAll());
+    this.registry.set('activeSlot', this.quickSlots.activeIndex);
+    this.registry.set('invWeight', this.inventory.getTotalWeight());
+    this.registry.set('invMaxWeight', this.inventory.maxWeight);
+    this.registry.set('invSlots', this.inventory.slotCount);
+    const counts = new Map<string, number>();
+    for (const item of this.inventory.getItems()) {
+      counts.set(item.id, item.count);
+    }
+    this.registry.set('invCounts', counts);
+  }
+
+  // ─── Boss Attack Logic ─────────────────────────────────────────
+
+  private handleBossEvents(events: BossPhaseEvent[], _delta: number): void {
+    for (const event of events) {
+      if (event.type === 'phase_change') {
+        const phaseName = BOSS_PHASE_NAMES_RU[event.phase];
+        this.showFeedback(`Фаза: ${phaseName}`);
+      }
+      if (event.type === 'cycle_complete') {
+        this.showFeedback(`Цикл ${event.cycleCount} завершён — Уроборос ускоряется!`);
+      }
+    }
+  }
+
+  private updateBossAttacks(delta: number): void {
+    const phase = this.bossState.currentPhase;
+    const bx = Position.x[this.bossEid];
+    const by = Position.y[this.bossEid];
+    const px = Position.x[this.playerEid];
+    const py = Position.y[this.playerEid];
+
+    switch (phase) {
+      case BossPhase.Coil: {
+        // Boss slowly moves toward player
+        const dx = px - bx;
+        const dy = py - by;
+        const dist = Math.sqrt(dx * dx + dy * dy);
+        if (dist > 30) {
+          const speed = 20 + this.bossState.cycleCount * 5;
+          Velocity.vx[this.bossEid] = (dx / dist) * speed;
+          Velocity.vy[this.bossEid] = (dy / dist) * speed;
+        } else {
+          Velocity.vx[this.bossEid] = 0;
+          Velocity.vy[this.bossEid] = 0;
+          // Close-range damage
+          this.bossAttackTimer -= delta;
+          if (this.bossAttackTimer <= 0) {
+            Health.current[this.playerEid] = Math.max(
+              0, (Health.current[this.playerEid] ?? 0) - this.bossData.damage * 0.5,
+            );
+            this.bossAttackTimer = 1500;
+          }
+        }
+        break;
+      }
+
+      case BossPhase.Spray: {
+        // Boss stays still, shoots acid projectiles in rotating pattern
+        Velocity.vx[this.bossEid] = 0;
+        Velocity.vy[this.bossEid] = 0;
+
+        this.bossAttackTimer -= delta;
+        if (this.bossAttackTimer <= 0) {
+          const sprayCount = 4 + this.bossState.cycleCount;
+          const baseAngle = (Date.now() / 1000) * 2; // Rotating
+          for (let i = 0; i < sprayCount; i++) {
+            const angle = baseAngle + (i * 2 * Math.PI / sprayCount);
+            const targetX = bx + Math.cos(angle) * 200;
+            const targetY = by + Math.sin(angle) * 200;
+            this.spawnBossProjectile(bx, by, targetX, targetY);
+          }
+          this.bossAttackTimer = 1500 - this.bossState.cycleCount * 150;
+        }
+        break;
+      }
+
+      case BossPhase.Lash: {
+        // Boss sweeps tail — area damage if player is in range + angle
+        Velocity.vx[this.bossEid] = 0;
+        Velocity.vy[this.bossEid] = 0;
+
+        this.bossAttackTimer -= delta;
+        if (this.bossAttackTimer <= 0) {
+          const dx = px - bx;
+          const dy = py - by;
+          const dist = Math.sqrt(dx * dx + dy * dy);
+          if (dist < 80 + this.bossState.cycleCount * 10) {
+            const damage = this.bossData.damage * (1 + this.bossState.cycleCount * 0.2);
+            Health.current[this.playerEid] = Math.max(
+              0, (Health.current[this.playerEid] ?? 0) - damage,
+            );
+            this.showFeedback(`Удар хвостом! (${Math.round(damage)} урона)`);
+          }
+          this.bossAttackTimer = 2000 - this.bossState.cycleCount * 200;
+        }
+        break;
+      }
+
+      case BossPhase.Digest: {
+        // Boss is immobile and vulnerable
+        Velocity.vx[this.bossEid] = 0;
+        Velocity.vy[this.bossEid] = 0;
+        break;
+      }
+    }
+  }
+
+  private spawnBossProjectile(fromX: number, fromY: number, toX: number, toY: number): void {
+    launchProjectile(
+      this.gameWorld.world,
+      this.projectileData,
+      fromX, fromY,
+      toX, toY,
+      '__boss_acid__',
+    );
+  }
+
+  // ─── Projectile → Boss Collision ───────────────────────────────
+
+  private checkProjectileBossCollision(): void {
+    const projEntities = query(this.gameWorld.world, [Position, Projectile]);
+    const bx = Position.x[this.bossEid];
+    const by = Position.y[this.bossEid];
+    const hitRadiusSq = (this.bossData.radius + 5) * (this.bossData.radius + 5);
+
+    for (const projEid of projEntities) {
+      const projInfo = this.projectileData.get(projEid);
+      if (!projInfo || projInfo.itemId === '__boss_acid__') continue; // Skip boss projectiles
+
+      const dx = Position.x[projEid] - bx;
+      const dy = Position.y[projEid] - by;
+      const distSq = dx * dx + dy * dy;
+
+      if (distSq <= hitRadiusSq) {
+        // Hit the boss!
+        const result = applyBossDamage(this.bossState, this.bossData, projInfo.itemId);
+
+        // Sync health to ECS
+        Health.current[this.bossEid] = this.bossState.health;
+
+        // Remove projectile
+        removeGameEntity(this.gameWorld.world, projEid);
+        this.projectileData.delete(projEid);
+
+        // Show feedback
+        this.showFeedback(result.messageRu);
+      }
+    }
+
+    // Check boss projectile → player collision
+    const px = Position.x[this.playerEid];
+    const py = Position.y[this.playerEid];
+    const playerHitRadiusSq = 15 * 15;
+
+    for (const projEid of projEntities) {
+      const projInfo = this.projectileData.get(projEid);
+      if (!projInfo || projInfo.itemId !== '__boss_acid__') continue;
+
+      const dx = Position.x[projEid] - px;
+      const dy = Position.y[projEid] - py;
+      const distSq = dx * dx + dy * dy;
+
+      if (distSq <= playerHitRadiusSq) {
+        // Boss projectile hits player
+        const damage = this.bossData.damage * 0.7;
+        Health.current[this.playerEid] = Math.max(
+          0, (Health.current[this.playerEid] ?? 0) - damage,
+        );
+        removeGameEntity(this.gameWorld.world, projEid);
+        this.projectileData.delete(projEid);
+      }
+    }
+  }
+
+  // ─── Boss Visual Effects ───────────────────────────────────────
+
+  private updateBossVisuals(_delta: number): void {
+    const bx = Position.x[this.bossEid];
+    const by = Position.y[this.bossEid];
+
+    this.bossGlowGraphics.clear();
+
+    // Phase-based glow
+    const phase = this.bossState.currentPhase;
+    let glowColor = 0xcc44ff;
+    let glowAlpha = 0.15;
+    let glowRadius = this.bossData.radius * 2;
+
+    switch (phase) {
+      case BossPhase.Coil:
+        glowColor = 0xff4444; // Red — danger
+        glowAlpha = 0.2;
+        break;
+      case BossPhase.Spray:
+        glowColor = 0x88ff00; // Acid green
+        glowAlpha = 0.25;
+        glowRadius = this.bossData.radius * 2.5;
+        break;
+      case BossPhase.Lash:
+        glowColor = 0xffaa00; // Orange — warning
+        glowAlpha = 0.2;
+        break;
+      case BossPhase.Digest:
+        glowColor = 0x4488ff; // Blue — vulnerable
+        glowAlpha = 0.3;
+        glowRadius = this.bossData.radius * 1.5;
+        break;
+    }
+
+    // Pulsing glow
+    const pulse = 0.7 + 0.3 * Math.sin(Date.now() / 300);
+    this.bossGlowGraphics.fillStyle(glowColor, glowAlpha * pulse);
+    this.bossGlowGraphics.fillCircle(bx, by, glowRadius);
+
+    // Inner glow
+    this.bossGlowGraphics.fillStyle(glowColor, glowAlpha * pulse * 1.5);
+    this.bossGlowGraphics.fillCircle(bx, by, glowRadius * 0.5);
+
+    // Catalyst poison visual: darkening stacks
+    if (this.bossState.catalystStacks > 0) {
+      const poisonAlpha = 0.1 * this.bossState.catalystStacks;
+      this.bossGlowGraphics.fillStyle(0x888888, poisonAlpha);
+      this.bossGlowGraphics.fillCircle(bx, by, this.bossData.radius * 1.2);
+    }
+  }
+
+  // ─── UI ────────────────────────────────────────────────────────
+
+  private createBossUI(): void {
+    const cam = this.cameras.main;
+
+    // Boss health bar background
+    this.bossHealthBar = this.add.graphics();
+    this.bossHealthBar.setScrollFactor(0);
+    this.bossHealthBar.setDepth(100);
+
+    // Boss name + health text
+    this.bossHealthText = this.add.text(cam.width / 2, 20, '', {
+      fontSize: '14px',
+      color: '#cc44ff',
+      fontFamily: 'monospace',
+      backgroundColor: '#000000cc',
+      padding: { x: 8, y: 4 },
+    });
+    this.bossHealthText.setScrollFactor(0);
+    this.bossHealthText.setOrigin(0.5, 0);
+    this.bossHealthText.setDepth(101);
+
+    // Phase indicator
+    this.phaseText = this.add.text(cam.width / 2, 55, '', {
+      fontSize: '12px',
+      color: '#ffdd44',
+      fontFamily: 'monospace',
+      backgroundColor: '#000000aa',
+      padding: { x: 6, y: 2 },
+    });
+    this.phaseText.setScrollFactor(0);
+    this.phaseText.setOrigin(0.5, 0);
+    this.phaseText.setDepth(101);
+
+    // Feedback text (center)
+    this.feedbackText = this.add.text(cam.width / 2, cam.height - 60, '', {
+      fontSize: '14px',
+      color: '#ffdd44',
+      fontFamily: 'monospace',
+      backgroundColor: '#000000cc',
+      padding: { x: 8, y: 4 },
+      align: 'center',
+    });
+    this.feedbackText.setScrollFactor(0);
+    this.feedbackText.setOrigin(0.5);
+    this.feedbackText.setDepth(101);
+    this.feedbackText.setAlpha(0);
+  }
+
+  private updateBossUI(): void {
+    const cam = this.cameras.main;
+    const healthPct = this.bossState.health / this.bossState.maxHealth;
+
+    // Fix UI positions for camera zoom.
+    // Graphics at (0,0) — local draw coordinates map 1:1 to screen pixels.
+    fixToScreen(this.bossHealthBar, 0, 0, cam);
+    fixToScreen(this.bossHealthText, cam.width / 2, 20, cam);
+    fixToScreen(this.phaseText, cam.width / 2, 55, cam);
+    fixToScreen(this.feedbackText, cam.width / 2, cam.height - 60, cam);
+
+    // Health bar
+    const barWidth = 300;
+    const barHeight = 8;
+    const barX = (cam.width - barWidth) / 2;
+    const barY = 42;
+
+    this.bossHealthBar.clear();
+    // Background
+    this.bossHealthBar.fillStyle(0x333333, 0.8);
+    this.bossHealthBar.fillRect(barX, barY, barWidth, barHeight);
+    // Fill
+    const fillColor = healthPct > 0.5 ? 0xcc44ff : healthPct > 0.25 ? 0xff8800 : 0xff2222;
+    this.bossHealthBar.fillStyle(fillColor, 1);
+    this.bossHealthBar.fillRect(barX, barY, barWidth * healthPct, barHeight);
+    // Border
+    this.bossHealthBar.lineStyle(1, 0xffffff, 0.3);
+    this.bossHealthBar.strokeRect(barX, barY, barWidth, barHeight);
+
+    // Health text
+    const healthStr = `УРОБОРОС — ${Math.ceil(this.bossState.health)}/${this.bossState.maxHealth}`;
+    this.bossHealthText.setText(healthStr);
+
+    // Phase text
+    const phaseName = BOSS_PHASE_NAMES_RU[this.bossState.currentPhase];
+    const cycleStr = this.bossState.cycleCount > 0 ? ` | Цикл ${this.bossState.cycleCount}` : '';
+    const catalystStr = this.bossState.catalystStacks > 0
+      ? ` | ☠ Яд: ${this.bossState.catalystStacks}/${this.bossData.maxCatalystStacks}`
+      : '';
+    const vulnStr = isVulnerable(this.bossState, this.bossData) ? ' | ★ УЯЗВИМ' : '';
+    this.phaseText.setText(`${phaseName}${vulnStr}${cycleStr}${catalystStr}`);
+
+    // Phase color
+    switch (this.bossState.currentPhase) {
+      case BossPhase.Coil:
+        this.phaseText.setColor('#ff4444');
+        break;
+      case BossPhase.Spray:
+        this.phaseText.setColor('#88ff00');
+        break;
+      case BossPhase.Lash:
+        this.phaseText.setColor('#ffaa00');
+        break;
+      case BossPhase.Digest:
+        this.phaseText.setColor('#4488ff');
+        break;
+    }
+  }
+
+  // ─── Victory & Death ───────────────────────────────────────────
+
+  private onBossDefeated(): void {
+    this.victoryAchieved = true;
+
+    // Calculate reward
+    const reward = calculateBossReward(this.bossState, this.bossData);
+    applyBossReward(this.meta, reward, this.runState.runId);
+
+    // Show victory message
+    const cam = this.cameras.main;
+    const victoryText = this.add.text(cam.width / 2, cam.height / 2, '', {
+      fontSize: '20px',
+      color: '#cc44ff',
+      fontFamily: 'monospace',
+      backgroundColor: '#000000ee',
+      padding: { x: 16, y: 12 },
+      align: 'center',
+      wordWrap: { width: 500 },
+    });
+    victoryText.setScrollFactor(0);
+    victoryText.setOrigin(0.5);
+    victoryText.setDepth(200);
+    fixToScreen(victoryText, cam.width / 2, cam.height / 2, cam);
+
+    const methodNames: Record<string, string> = {
+      chemical: 'Алхимическая победа (NaOH)',
+      direct: 'Прямая победа',
+      catalytic: 'Каталитическая победа (Hg)',
+    };
+    const method = this.bossState.victoryMethod ?? 'direct';
+    const methodName = methodNames[method] ?? method;
+
+    victoryText.setText(
+      `★ УРОБОРОС ПОВЕРЖЕН ★\n\n${methodName}\n+${reward.spores} спор\n\nАрхонтова Память добавлена в Кодекс`,
+    );
+
+    // Stop UIScene
+    this.scene.stop('UIScene');
+
+    // Transition after delay
+    this.time.delayedCall(4000, () => {
+      this.cameras.main.fadeOut(1500, 0, 0, 0);
+      this.cameras.main.once('camerafadeoutcomplete', () => {
+        this.scene.start('DeathScene', {
+          meta: this.meta,
+          runState: this.runState,
+        });
+      });
+    });
+  }
+
+  private onPlayerDeath(): void {
+    this.playerDead = true;
+    this.runState.alive = false;
+
+    this.scene.stop('UIScene');
+
+    this.cameras.main.fadeOut(2000, 0, 0, 0);
+    this.cameras.main.once('camerafadeoutcomplete', () => {
+      this.scene.start('DeathScene', {
+        meta: this.meta,
+        runState: this.runState,
+      });
+    });
+  }
+
+  // ─── Projectile Launch ─────────────────────────────────────────
+
+  private tryLaunchProjectile(): void {
+    const itemId = this.quickSlots.getActive();
+    if (!itemId || !this.inventory.hasItem(itemId)) return;
+
+    const removed = this.inventory.removeItem(itemId, 1);
+    if (removed === 0) return;
+
+    const pointer = this.input.activePointer;
+    const worldPoint = this.cameras.main.getWorldPoint(pointer.x, pointer.y);
+
+    launchProjectile(
+      this.gameWorld.world,
+      this.projectileData,
+      Position.x[this.playerEid],
+      Position.y[this.playerEid],
+      worldPoint.x,
+      worldPoint.y,
+      itemId,
+    );
+
+    // Clear quick slot if empty
+    if (!this.inventory.hasItem(itemId)) {
+      const slotIdx = this.quickSlots.getAll().indexOf(itemId);
+      if (slotIdx >= 0) this.quickSlots.assign(slotIdx, null);
+    }
+  }
+
+  // ─── Feedback ──────────────────────────────────────────────────
+
+  private showFeedback(message: string): void {
+    this.feedbackText.setText(message);
+    this.feedbackText.setAlpha(1);
+    this.feedbackTimer = 2500;
+  }
+}

src/scenes/CradleScene.ts

@@ -0,0 +1,591 @@
+/**
+ * CradleScene — Spore Cradle (Споровая Колыбель)
+ *
+ * Awakening scene where the player "wakes up" inside a giant mushroom.
+ * Displays school selection and starts the run.
+ * Receives meta state from BootScene or FractalScene.
+ */
+
+import Phaser from 'phaser';
+import schoolsData from '../data/schools.json';
+import biomeDataArray from '../data/biomes.json';
+import type { SchoolData, MetaState } from '../run/types';
+import type { BiomeData } from '../world/types';
+import { isSchoolUnlocked } from '../run/meta';
+import { GAME_WIDTH, GAME_HEIGHT } from '../config';
+import { getAvailableBonuses, purchaseBonus, canAffordBonus, resetShopSession } from '../mycelium/shop';
+import { getGraphStats } from '../mycelium/graph';
+import { getCycleSummary } from '../run/cycle';
+import { CYCLE_THEME_NAMES_RU } from '../run/types';
+import type { BonusEffect } from '../mycelium/types';
+import narrativeData from '../data/cycle-narrative.json';
+
+const schools = schoolsData as unknown as SchoolData[];
+const biomes = biomeDataArray as BiomeData[];
+
+export class CradleScene extends Phaser.Scene {
+  private meta!: MetaState;
+  private selectedIndex = 0;
+  private selectedBiomeIndex = 0;
+  private schoolCards: Phaser.GameObjects.Container[] = [];
+  private biomeCards: { bg: Phaser.GameObjects.Rectangle; label: Phaser.GameObjects.Text }[] = [];
+  private particles: { x: number; y: number; vx: number; vy: number; alpha: number; radius: number }[] = [];
+  private particleGraphics!: Phaser.GameObjects.Graphics;
+  private introTimer = 0;
+  private introComplete = false;
+  private purchasedEffects: BonusEffect[] = [];
+  private sporeCountText!: Phaser.GameObjects.Text;
+  private shopContainer!: Phaser.GameObjects.Container;
+
+  constructor() {
+    super({ key: 'CradleScene' });
+  }
+
+  init(data: { meta: MetaState }): void {
+    this.meta = data.meta;
+    this.selectedIndex = 0;
+    this.selectedBiomeIndex = 0;
+    this.schoolCards = [];
+    this.biomeCards = [];
+    this.introTimer = 0;
+    this.introComplete = false;
+    this.purchasedEffects = [];
+    resetShopSession();
+  }
+
+  create(): void {
+    const cx = GAME_WIDTH / 2;
+    const cy = GAME_HEIGHT / 2;
+
+    // Background — dark organic interior
+    this.cameras.main.setBackgroundColor('#050808');
+
+    // Ambient spore particles
+    this.particles = [];
+    for (let i = 0; i < 60; i++) {
+      this.particles.push({
+        x: Math.random() * GAME_WIDTH,
+        y: Math.random() * GAME_HEIGHT,
+        vx: (Math.random() - 0.5) * 15,
+        vy: -Math.random() * 20 - 5,
+        alpha: Math.random() * 0.4 + 0.1,
+        radius: Math.random() * 2 + 1,
+      });
+    }
+    this.particleGraphics = this.add.graphics();
+    this.particleGraphics.setDepth(0);
+
+    // Intro text — fades in
+    const introText = this.add.text(cx, cy - 60, '...пробуждение...', {
+      fontSize: '24px',
+      color: '#2a6644',
+      fontFamily: 'monospace',
+    });
+    introText.setOrigin(0.5);
+    introText.setAlpha(0);
+    introText.setDepth(10);
+
+    // Fade in intro
+    this.tweens.add({
+      targets: introText,
+      alpha: 1,
+      duration: 2000,
+      ease: 'Sine.easeIn',
+      onComplete: () => {
+        // After intro text appears, fade it out and show school selection
+        this.tweens.add({
+          targets: introText,
+          alpha: 0,
+          duration: 1500,
+          delay: 1000,
+          ease: 'Sine.easeOut',
+          onComplete: () => {
+            introText.destroy();
+            this.showSchoolSelection();
+            this.introComplete = true;
+          },
+        });
+      },
+    });
+
+    // Meta info (top-right)
+    const graphStats = getGraphStats(this.meta.mycelium);
+    const cycleSummary = getCycleSummary(this.meta.greatCycle);
+    const themeName = CYCLE_THEME_NAMES_RU[cycleSummary.theme];
+
+    const metaInfo = [
+      `Раны: ${this.meta.totalRuns}`,
+      `Кодекс: ${this.meta.codex.length}`,
+      `Мицелий: ${graphStats.nodeCount} узлов`,
+    ].join(' | ');
+    this.add.text(GAME_WIDTH - 12, 12, metaInfo, {
+      fontSize: '11px',
+      color: '#334433',
+      fontFamily: 'monospace',
+    }).setOrigin(1, 0).setDepth(10);
+
+    // Spore count (top-right, below meta info)
+    this.sporeCountText = this.add.text(GAME_WIDTH - 12, 28, `🍄 Споры: ${this.meta.spores}`, {
+      fontSize: '13px',
+      color: '#44ff88',
+      fontFamily: 'monospace',
+    });
+    this.sporeCountText.setOrigin(1, 0).setDepth(10);
+
+    // Cycle info (top-right, below spores)
+    const cycleInfo = `Великий Цикл ${cycleSummary.cycleNumber}: ${themeName} | Ран ${cycleSummary.runInCycle}/${cycleSummary.totalRuns}`;
+    this.add.text(GAME_WIDTH - 12, 46, cycleInfo, {
+      fontSize: '11px',
+      color: '#336644',
+      fontFamily: 'monospace',
+    }).setOrigin(1, 0).setDepth(10);
+
+    // Cycle narrative quote (top-left, fades in slowly)
+    const themeNarrative = (narrativeData.themes as Record<string, { cradleQuoteRu: string }>)[cycleSummary.theme];
+    if (themeNarrative) {
+      const quoteText = this.add.text(12, 12, themeNarrative.cradleQuoteRu, {
+        fontSize: '12px',
+        color: '#223322',
+        fontFamily: 'monospace',
+        fontStyle: 'italic',
+      });
+      quoteText.setAlpha(0);
+      quoteText.setDepth(10);
+      this.tweens.add({
+        targets: quoteText,
+        alpha: 0.5,
+        duration: 3000,
+        delay: 1000,
+      });
+    }
+  }
+
+  private showSchoolSelection(): void {
+    const cx = GAME_WIDTH / 2;
+
+    // Title
+    const title = this.add.text(cx, 30, 'СПОРОВАЯ КОЛЫБЕЛЬ', {
+      fontSize: '28px',
+      color: '#00ff88',
+      fontFamily: 'monospace',
+      fontStyle: 'bold',
+    });
+    title.setOrigin(0.5);
+    title.setAlpha(0);
+    title.setDepth(10);
+
+    const subtitle = this.add.text(cx, 65, 'Выбери биом и школу', {
+      fontSize: '14px',
+      color: '#557755',
+      fontFamily: 'monospace',
+    });
+    subtitle.setOrigin(0.5);
+    subtitle.setAlpha(0);
+    subtitle.setDepth(10);
+
+    this.tweens.add({ targets: [title, subtitle], alpha: 1, duration: 800 });
+
+    // Biome selection row
+    this.createBiomeSelector(cx, 105);
+
+    // School cards — show ALL schools, grayed out if locked
+    const cardWidth = 280;
+    const cardHeight = 220;
+    const startY = 150;
+    const cardSpacing = 12;
+
+    for (let i = 0; i < schools.length; i++) {
+      const school = schools[i];
+      const unlocked = isSchoolUnlocked(this.meta, school.id);
+      const totalCardWidth = schools.length * (cardWidth + cardSpacing) - cardSpacing;
+      const cardX = cx - totalCardWidth / 2 + cardWidth / 2 + i * (cardWidth + cardSpacing);
+      const cardY = startY + cardHeight / 2;
+
+      const container = this.add.container(cardX, cardY);
+      container.setDepth(10);
+
+      const schoolColor = parseInt(school.color.replace('#', ''), 16);
+
+      // Card background
+      const bg = this.add.rectangle(0, 0, cardWidth, cardHeight,
+        unlocked ? 0x0a1a0f : 0x0a0a0a, 0.9);
+      bg.setStrokeStyle(2, unlocked ? schoolColor : 0x333333);
+      container.add(bg);
+
+      // School name
+      const nameText = this.add.text(0, -cardHeight / 2 + 20, school.nameRu, {
+        fontSize: '20px',
+        color: unlocked ? school.color : '#555555',
+        fontFamily: 'monospace',
+        fontStyle: 'bold',
+      });
+      nameText.setOrigin(0.5);
+      container.add(nameText);
+
+      // Principle
+      const principleText = this.add.text(0, -cardHeight / 2 + 48, school.principleRu, {
+        fontSize: '11px',
+        color: unlocked ? '#88aa88' : '#444444',
+        fontFamily: 'monospace',
+      });
+      principleText.setOrigin(0.5);
+      container.add(principleText);
+
+      if (unlocked) {
+        // ─── Unlocked school: full info ───
+
+        // Starting elements
+        const elemList = school.startingElements.map(sym => {
+          const qty = school.startingQuantities[sym] ?? 1;
+          return `${sym} ×${qty}`;
+        }).join('  ');
+        const elemText = this.add.text(0, -cardHeight / 2 + 72, elemList, {
+          fontSize: '12px',
+          color: '#aaffaa',
+          fontFamily: 'monospace',
+        });
+        elemText.setOrigin(0.5);
+        container.add(elemText);
+
+        // Bonus indicator
+        const bonusKeys = Object.keys(school.bonuses);
+        if (bonusKeys.length > 0) {
+          const bonusLabels: Record<string, string> = {
+            reactionEfficiency: 'Реакции',
+            projectileDamage: 'Урон',
+            creatureAggroRange: 'Агрессия',
+            movementSpeed: 'Скорость',
+          };
+          const bonusText = bonusKeys.map(k => {
+            const label = bonusLabels[k] ?? k;
+            const val = school.bonuses[k];
+            const pct = val >= 1 ? `+${Math.round((val - 1) * 100)}%` : `-${Math.round((1 - val) * 100)}%`;
+            return `${label} ${pct}`;
+          }).join('  ');
+          const bText = this.add.text(0, -cardHeight / 2 + 95, bonusText, {
+            fontSize: '11px',
+            color: '#ffcc44',
+            fontFamily: 'monospace',
+          });
+          bText.setOrigin(0.5);
+          container.add(bText);
+        }
+
+        // Playstyle
+        const playText = this.add.text(0, -cardHeight / 2 + 118,
+          this.wrapText(school.playstyleRu, 30), {
+            fontSize: '11px',
+            color: '#778877',
+            fontFamily: 'monospace',
+            lineSpacing: 3,
+          });
+        playText.setOrigin(0.5, 0);
+        container.add(playText);
+
+        // Description
+        const descText = this.add.text(0, cardHeight / 2 - 55,
+          this.wrapText(school.descriptionRu, 30), {
+            fontSize: '10px',
+            color: '#556655',
+            fontFamily: 'monospace',
+            lineSpacing: 2,
+          });
+        descText.setOrigin(0.5, 0);
+        container.add(descText);
+
+        // Click to select
+        bg.setInteractive({ useHandCursor: true });
+        bg.on('pointerover', () => {
+          bg.setStrokeStyle(3, 0x00ff88);
+          this.selectedIndex = i;
+        });
+        bg.on('pointerout', () => {
+          bg.setStrokeStyle(2, schoolColor);
+        });
+        bg.on('pointerdown', () => {
+          this.startRun(school);
+        });
+      } else {
+        // ─── Locked school: grayed out with unlock hint ───
+
+        // Lock icon
+        const lockText = this.add.text(0, -10, '🔒', {
+          fontSize: '32px',
+        });
+        lockText.setOrigin(0.5);
+        container.add(lockText);
+
+        // Unlock hint
+        const hint = school.unlockCondition?.hintRu ?? 'Заблокировано';
+        const hintText = this.add.text(0, 30, hint, {
+          fontSize: '11px',
+          color: '#666666',
+          fontFamily: 'monospace',
+          align: 'center',
+        });
+        hintText.setOrigin(0.5);
+        container.add(hintText);
+      }
+
+      // Fade in
+      container.setAlpha(0);
+      this.tweens.add({
+        targets: container,
+        alpha: unlocked ? 1 : 0.6,
+        duration: 600,
+        delay: 200 + i * 150,
+      });
+
+      this.schoolCards.push(container);
+    }
+
+    // Spore shop (bottom area, only if player has spores)
+    if (this.meta.spores > 0) {
+      this.createSporeShop(cx);
+    }
+
+    // Start button hint
+    const hintText = this.add.text(cx, GAME_HEIGHT - 40, '[ Нажми на школу, чтобы начать ран ]', {
+      fontSize: '13px',
+      color: '#445544',
+      fontFamily: 'monospace',
+    });
+    hintText.setOrigin(0.5);
+    hintText.setAlpha(0);
+    hintText.setDepth(10);
+    this.tweens.add({
+      targets: hintText,
+      alpha: 0.8,
+      duration: 600,
+      delay: 600,
+      yoyo: true,
+      repeat: -1,
+    });
+  }
+
+  /** Create the spore shop UI below school cards */
+  private createSporeShop(cx: number): void {
+    this.shopContainer = this.add.container(0, 0);
+    this.shopContainer.setDepth(10);
+
+    const shopY = 440;
+    const shopTitle = this.add.text(cx, shopY, '🍄 Дары Мицелия (потрать споры)', {
+      fontSize: '13px',
+      color: '#33aa66',
+      fontFamily: 'monospace',
+    });
+    shopTitle.setOrigin(0.5);
+    this.shopContainer.add(shopTitle);
+
+    const bonuses = getAvailableBonuses();
+    const btnWidth = 200;
+    const btnHeight = 50;
+    const spacing = 10;
+    const totalWidth = bonuses.length * (btnWidth + spacing) - spacing;
+    const startX = cx - totalWidth / 2 + btnWidth / 2;
+
+    for (let i = 0; i < bonuses.length; i++) {
+      const bonus = bonuses[i];
+      const bx = startX + i * (btnWidth + spacing);
+      const by = shopY + 45;
+
+      const bg = this.add.rectangle(bx, by, btnWidth, btnHeight, 0x0a1a0f, 0.85);
+      const canBuy = canAffordBonus(this.meta, bonus.id);
+      const borderColor = canBuy ? 0x33cc66 : 0x333333;
+      bg.setStrokeStyle(1, borderColor);
+      this.shopContainer.add(bg);
+
+      const label = this.add.text(bx, by - 10, bonus.nameRu, {
+        fontSize: '11px',
+        color: canBuy ? '#88ffaa' : '#555555',
+        fontFamily: 'monospace',
+      });
+      label.setOrigin(0.5);
+      this.shopContainer.add(label);
+
+      const costText = this.add.text(bx, by + 10, `${bonus.cost} спор`, {
+        fontSize: '10px',
+        color: canBuy ? '#44aa66' : '#444444',
+        fontFamily: 'monospace',
+      });
+      costText.setOrigin(0.5);
+      this.shopContainer.add(costText);
+
+      if (canBuy) {
+        bg.setInteractive({ useHandCursor: true });
+        bg.on('pointerover', () => bg.setStrokeStyle(2, 0x00ff88));
+        bg.on('pointerout', () => bg.setStrokeStyle(1, 0x33cc66));
+        bg.on('pointerdown', () => {
+          const effect = purchaseBonus(this.meta, bonus.id);
+          if (effect) {
+            this.purchasedEffects.push(effect);
+            this.sporeCountText.setText(`🍄 Споры: ${this.meta.spores}`);
+
+            // Visual feedback
+            bg.setFillStyle(0x1a3a1f, 0.9);
+            label.setColor('#ffffff');
+            costText.setText('✓ куплено');
+            costText.setColor('#00ff88');
+            bg.removeInteractive();
+
+            // Refresh other buttons' affordability
+            this.refreshShopButtons();
+          }
+        });
+      }
+    }
+
+    // Fade in shop
+    this.shopContainer.setAlpha(0);
+    this.tweens.add({
+      targets: this.shopContainer,
+      alpha: 1,
+      duration: 600,
+      delay: 800,
+    });
+  }
+
+  /** Refresh shop button states after a purchase */
+  private refreshShopButtons(): void {
+    // Destroy and recreate shop — simplest approach
+    if (this.shopContainer) {
+      this.shopContainer.destroy();
+    }
+    if (this.meta.spores > 0) {
+      this.createSporeShop(GAME_WIDTH / 2);
+      this.shopContainer.setAlpha(1);
+    }
+  }
+
+  /** Create the biome selection row */
+  private createBiomeSelector(cx: number, y: number): void {
+    const btnWidth = 200;
+    const btnHeight = 36;
+    const spacing = 12;
+    const totalWidth = biomes.length * (btnWidth + spacing) - spacing;
+    const startX = cx - totalWidth / 2 + btnWidth / 2;
+
+    const biomeColors: Record<string, number> = {
+      'catalytic-wastes': 0x886622,
+      'kinetic-mountains': 0x5577aa,
+      'verdant-forests': 0x228833,
+    };
+
+    for (let i = 0; i < biomes.length; i++) {
+      const biome = biomes[i];
+      const bx = startX + i * (btnWidth + spacing);
+      const isSelected = i === this.selectedBiomeIndex;
+      const color = biomeColors[biome.id] ?? 0x444444;
+
+      const bg = this.add.rectangle(bx, y, btnWidth, btnHeight,
+        isSelected ? color : 0x0a1a0f, 0.9);
+      bg.setStrokeStyle(isSelected ? 3 : 1, color);
+      bg.setDepth(10);
+
+      const label = this.add.text(bx, y, biome.nameRu, {
+        fontSize: '13px',
+        color: isSelected ? '#ffffff' : '#888888',
+        fontFamily: 'monospace',
+        fontStyle: isSelected ? 'bold' : 'normal',
+      });
+      label.setOrigin(0.5);
+      label.setDepth(10);
+
+      bg.setInteractive({ useHandCursor: true });
+      bg.on('pointerdown', () => {
+        this.selectedBiomeIndex = i;
+        this.refreshBiomeButtons();
+      });
+      bg.on('pointerover', () => {
+        if (i !== this.selectedBiomeIndex) {
+          bg.setStrokeStyle(2, 0x00ff88);
+        }
+      });
+      bg.on('pointerout', () => {
+        const sel = i === this.selectedBiomeIndex;
+        bg.setStrokeStyle(sel ? 3 : 1, color);
+      });
+
+      // Fade in
+      bg.setAlpha(0);
+      label.setAlpha(0);
+      this.tweens.add({ targets: [bg, label], alpha: 1, duration: 600, delay: 100 + i * 100 });
+
+      this.biomeCards.push({ bg, label });
+    }
+  }
+
+  /** Refresh biome button visual states */
+  private refreshBiomeButtons(): void {
+    const biomeColors: Record<string, number> = {
+      'catalytic-wastes': 0x886622,
+      'kinetic-mountains': 0x5577aa,
+      'verdant-forests': 0x228833,
+    };
+
+    for (let i = 0; i < this.biomeCards.length; i++) {
+      const card = this.biomeCards[i];
+      const biome = biomes[i];
+      const isSelected = i === this.selectedBiomeIndex;
+      const color = biomeColors[biome.id] ?? 0x444444;
+
+      card.bg.setFillStyle(isSelected ? color : 0x0a1a0f, 0.9);
+      card.bg.setStrokeStyle(isSelected ? 3 : 1, color);
+      card.label.setColor(isSelected ? '#ffffff' : '#888888');
+      card.label.setFontStyle(isSelected ? 'bold' : 'normal');
+    }
+  }
+
+  private startRun(school: SchoolData): void {
+    // Flash effect
+    this.cameras.main.flash(300, 0, 255, 136);
+
+    const selectedBiome = biomes[this.selectedBiomeIndex];
+
+    this.time.delayedCall(400, () => {
+      this.scene.start('GameScene', {
+        meta: this.meta,
+        schoolId: school.id,
+        runId: this.meta.totalRuns + 1,
+        purchasedEffects: this.purchasedEffects,
+        biomeId: selectedBiome.id,
+      });
+    });
+  }
+
+  update(_time: number, delta: number): void {
+    // Animate spore particles
+    this.particleGraphics.clear();
+    for (const p of this.particles) {
+      p.x += p.vx * (delta / 1000);
+      p.y += p.vy * (delta / 1000);
+      p.alpha += (Math.random() - 0.5) * 0.01;
+      p.alpha = Math.max(0.05, Math.min(0.5, p.alpha));
+
+      // Wrap around
+      if (p.y < -5) p.y = GAME_HEIGHT + 5;
+      if (p.x < -5) p.x = GAME_WIDTH + 5;
+      if (p.x > GAME_WIDTH + 5) p.x = -5;
+
+      this.particleGraphics.fillStyle(0x00ff88, p.alpha);
+      this.particleGraphics.fillCircle(p.x, p.y, p.radius);
+    }
+  }
+
+  /** Simple word wrap by character count */
+  private wrapText(text: string, maxChars: number): string {
+    const words = text.split(' ');
+    const lines: string[] = [];
+    let currentLine = '';
+    for (const word of words) {
+      if (currentLine.length + word.length + 1 > maxChars) {
+        lines.push(currentLine);
+        currentLine = word;
+      } else {
+        currentLine += (currentLine.length > 0 ? ' ' : '') + word;
+      }
+    }
+    if (currentLine.length > 0) lines.push(currentLine);
+    return lines.join('\n');
+  }
+}

src/scenes/DeathScene.ts

@@ -0,0 +1,261 @@
+/**
+ * DeathScene — Body decomposition and transition to fractal
+ *
+ * GDD spec:
+ * 1. World slows, sounds fade
+ * 2. Body decomposes into real elements (65% O, 18% C, 10% H...)
+ * 3. Elements absorbed into soil → rush toward Mycelium
+ * 4. Transition to FractalScene
+ */
+
+import Phaser from 'phaser';
+import type { MetaState, RunState } from '../run/types';
+import { BODY_COMPOSITION } from '../run/types';
+import { ElementRegistry } from '../chemistry/elements';
+import { GAME_WIDTH, GAME_HEIGHT } from '../config';
+
+/** A single element particle flying out during decomposition */
+interface DeathParticle {
+  x: number;
+  y: number;
+  vx: number;
+  vy: number;
+  color: number;
+  symbol: string;
+  alpha: number;
+  radius: number;
+  phase: 'explode' | 'settle' | 'absorb';
+  timer: number;
+}
+
+export class DeathScene extends Phaser.Scene {
+  private meta!: MetaState;
+  private runState!: RunState;
+  private particles: DeathParticle[] = [];
+  private graphics!: Phaser.GameObjects.Graphics;
+  private elapsed = 0;
+  private phaseState: 'decompose' | 'absorb' | 'fadeout' = 'decompose';
+  private labelTexts: Phaser.GameObjects.Text[] = [];
+  private compositionText!: Phaser.GameObjects.Text;
+
+  constructor() {
+    super({ key: 'DeathScene' });
+  }
+
+  init(data: { meta: MetaState; runState: RunState }): void {
+    this.meta = data.meta;
+    this.runState = data.runState;
+    this.particles = [];
+    this.elapsed = 0;
+    this.phaseState = 'decompose';
+    this.labelTexts = [];
+  }
+
+  create(): void {
+    this.cameras.main.setBackgroundColor('#020202');
+    this.graphics = this.add.graphics();
+
+    const cx = GAME_WIDTH / 2;
+    const cy = GAME_HEIGHT / 2;
+
+    // Player "body" — starts as a bright circle, then decomposes
+    const bodyGlow = this.add.circle(cx, cy, 16, 0x00e5ff, 1);
+    bodyGlow.setDepth(10);
+
+    // Title text
+    const deathText = this.add.text(cx, 60, 'Распад...', {
+      fontSize: '20px',
+      color: '#334455',
+      fontFamily: 'monospace',
+    });
+    deathText.setOrigin(0.5);
+    deathText.setAlpha(0);
+
+    // Composition display
+    this.compositionText = this.add.text(cx, GAME_HEIGHT - 50, '', {
+      fontSize: '11px',
+      color: '#445566',
+      fontFamily: 'monospace',
+    });
+    this.compositionText.setOrigin(0.5);
+    this.compositionText.setAlpha(0);
+
+    // Phase 1: Body pulses, then explodes into elements
+    this.tweens.add({
+      targets: bodyGlow,
+      scaleX: 1.5,
+      scaleY: 1.5,
+      alpha: 0.7,
+      duration: 600,
+      yoyo: true,
+      repeat: 2,
+      ease: 'Sine.easeInOut',
+      onComplete: () => {
+        // Explode into element particles
+        this.spawnElementParticles(cx, cy);
+        bodyGlow.destroy();
+
+        // Show death text
+        this.tweens.add({
+          targets: deathText,
+          alpha: 0.6,
+          duration: 1000,
+        });
+
+        // Show composition
+        const compText = BODY_COMPOSITION
+          .map(e => `${e.symbol}: ${(e.fraction * 100).toFixed(1)}%`)
+          .join('  ');
+        this.compositionText.setText(`Элементный состав: ${compText}`);
+        this.tweens.add({
+          targets: this.compositionText,
+          alpha: 0.5,
+          duration: 2000,
+          delay: 500,
+        });
+      },
+    });
+
+    // After 6 seconds, start absorb phase
+    this.time.delayedCall(5500, () => {
+      this.phaseState = 'absorb';
+      this.tweens.add({
+        targets: deathText,
+        alpha: 0,
+        duration: 800,
+      });
+    });
+
+    // After 8 seconds, transition to fractal
+    this.time.delayedCall(8000, () => {
+      this.phaseState = 'fadeout';
+      this.cameras.main.fadeOut(1500, 0, 0, 0);
+      this.cameras.main.once('camerafadeoutcomplete', () => {
+        this.scene.start('FractalScene', {
+          meta: this.meta,
+          runState: this.runState,
+        });
+      });
+    });
+  }
+
+  private spawnElementParticles(cx: number, cy: number): void {
+    const totalParticles = 80;
+
+    for (const comp of BODY_COMPOSITION) {
+      const count = Math.max(1, Math.round(comp.fraction * totalParticles));
+      const elem = ElementRegistry.getBySymbol(comp.symbol);
+      const color = elem ? parseInt(elem.color.replace('#', ''), 16) : 0xffffff;
+
+      for (let i = 0; i < count; i++) {
+        const angle = Math.random() * Math.PI * 2;
+        const speed = 40 + Math.random() * 120;
+        this.particles.push({
+          x: cx + (Math.random() - 0.5) * 6,
+          y: cy + (Math.random() - 0.5) * 6,
+          vx: Math.cos(angle) * speed,
+          vy: Math.sin(angle) * speed,
+          color,
+          symbol: comp.symbol,
+          alpha: 0.8 + Math.random() * 0.2,
+          radius: 2 + comp.fraction * 6,
+          phase: 'explode',
+          timer: 0,
+        });
+      }
+
+      // Add a visible label for the most abundant elements
+      if (comp.fraction >= 0.03) {
+        const labelAngle = Math.random() * Math.PI * 2;
+        const labelDist = 60 + comp.fraction * 200;
+        const labelText = this.add.text(
+          cx + Math.cos(labelAngle) * labelDist,
+          cy + Math.sin(labelAngle) * labelDist,
+          `${comp.symbol} ${(comp.fraction * 100).toFixed(0)}%`,
+          {
+            fontSize: '13px',
+            color: `#${color.toString(16).padStart(6, '0')}`,
+            fontFamily: 'monospace',
+          },
+        );
+        labelText.setOrigin(0.5);
+        labelText.setAlpha(0);
+        this.tweens.add({
+          targets: labelText,
+          alpha: 0.7,
+          duration: 800,
+          delay: 200 + Math.random() * 600,
+        });
+        this.labelTexts.push(labelText);
+      }
+    }
+  }
+
+  update(_time: number, delta: number): void {
+    this.elapsed += delta;
+    const dt = delta / 1000;
+
+    this.graphics.clear();
+
+    const cx = GAME_WIDTH / 2;
+    const cy = GAME_HEIGHT / 2;
+
+    for (const p of this.particles) {
+      p.timer += delta;
+
+      if (this.phaseState === 'decompose') {
+        // Particles fly outward, then slow down
+        p.vx *= 0.98;
+        p.vy *= 0.98;
+        p.x += p.vx * dt;
+        p.y += p.vy * dt;
+      } else if (this.phaseState === 'absorb') {
+        // Particles get pulled toward center-bottom (into "soil"/Mycelium)
+        const targetX = cx + (Math.random() - 0.5) * 20;
+        const targetY = GAME_HEIGHT + 20;
+        const dx = targetX - p.x;
+        const dy = targetY - p.y;
+        const dist = Math.sqrt(dx * dx + dy * dy);
+        if (dist > 1) {
+          p.vx += (dx / dist) * 200 * dt;
+          p.vy += (dy / dist) * 200 * dt;
+        }
+        p.x += p.vx * dt;
+        p.y += p.vy * dt;
+        p.alpha *= 0.995;
+      } else {
+        // Fadeout — everything fades
+        p.alpha *= 0.97;
+      }
+
+      // Draw particle
+      if (p.alpha > 0.02) {
+        this.graphics.fillStyle(p.color, p.alpha);
+        this.graphics.fillCircle(p.x, p.y, p.radius);
+      }
+    }
+
+    // Fade labels during absorb
+    if (this.phaseState === 'absorb' || this.phaseState === 'fadeout') {
+      for (const label of this.labelTexts) {
+        label.setAlpha(label.alpha * 0.98);
+      }
+    }
+
+    // Draw "Mycelium threads" rushing down during absorb
+    if (this.phaseState === 'absorb') {
+      this.graphics.lineStyle(1, 0x00ff88, 0.15);
+      for (let i = 0; i < 5; i++) {
+        const tx = cx + (Math.random() - 0.5) * 200;
+        this.graphics.beginPath();
+        this.graphics.moveTo(tx, cy);
+        let y = cy;
+        for (let j = 0; j < 8; j++) {
+          y += 30 + Math.random() * 20;
+          this.graphics.lineTo(tx + (Math.random() - 0.5) * 30, y);
+        }
+        this.graphics.strokePath();
+      }
+    }
+  }
+}

src/scenes/FractalScene.ts

@@ -0,0 +1,335 @@
+/**
+ * FractalScene — "Момент между" (Moment Between)
+ *
+ * GDD spec:
+ * 10-30 seconds of pure fractal visual. Myriad cycles flash before eyes.
+ * Looping patterns of births and deaths, infinitely nested.
+ * This is a REWARD, not punishment for dying.
+ *
+ * Uses a WebGL shader (Mandelbrot/Julia set hybrid) with cycling parameters.
+ * Falls back to a simpler canvas animation if WebGL pipeline unavailable.
+ */
+
+import Phaser from 'phaser';
+import type { MetaState, RunState } from '../run/types';
+import { applyRunResults } from '../run/meta';
+import { saveMetaState } from '../run/persistence';
+import { GAME_WIDTH, GAME_HEIGHT } from '../config';
+
+// ─── Fractal Fragment Shader ─────────────────────────────────────
+
+const FRACTAL_FRAG = `
+precision mediump float;
+
+uniform float uTime;
+uniform vec2 uResolution;
+uniform float uZoom;
+uniform vec2 uCenter;
+uniform float uMorphFactor;
+
+vec3 palette(float t) {
+  // Cyclic color palette — greens/teals/purples (Synthesis color scheme)
+  vec3 a = vec3(0.02, 0.05, 0.03);
+  vec3 b = vec3(0.0, 0.6, 0.4);
+  vec3 c = vec3(1.0, 1.0, 1.0);
+  vec3 d = vec3(0.0, 0.33, 0.53);
+  return a + b * cos(6.28318 * (c * t + d));
+}
+
+void main() {
+  vec2 uv = (gl_FragCoord.xy - uResolution * 0.5) / min(uResolution.x, uResolution.y);
+  uv = uv / uZoom + uCenter;
+
+  // Morph between Mandelbrot and Julia set
+  vec2 c = mix(uv, vec2(
+    0.355 + sin(uTime * 0.1) * 0.1,
+    0.355 + cos(uTime * 0.13) * 0.1
+  ), uMorphFactor);
+
+  vec2 z = mix(vec2(0.0), uv, uMorphFactor);
+  z = mix(uv, z, uMorphFactor);
+
+  float iterations = 0.0;
+  const float maxIter = 128.0;
+
+  for (float i = 0.0; i < maxIter; i++) {
+    // z = z^2 + c with slight twist
+    float xTemp = z.x * z.x - z.y * z.y + c.x;
+    z.y = 2.0 * z.x * z.y + c.y;
+    z.x = xTemp;
+
+    if (dot(z, z) > 4.0) {
+      iterations = i;
+      break;
+    }
+    iterations = i;
+  }
+
+  // Smooth coloring
+  float smoothIter = iterations;
+  if (iterations < maxIter - 1.0) {
+    float logZn = log(dot(z, z)) / 2.0;
+    float nu = log(logZn / log(2.0)) / log(2.0);
+    smoothIter = iterations + 1.0 - nu;
+  }
+
+  float t = smoothIter / maxIter;
+  t = t + uTime * 0.03; // Slow color cycling
+
+  vec3 color = palette(t);
+
+  // Vignette — darker at edges
+  vec2 vigUv = gl_FragCoord.xy / uResolution;
+  float vig = 1.0 - dot(vigUv - 0.5, vigUv - 0.5) * 1.5;
+  color *= vig;
+
+  // Inside the set — deep dark with faint glow
+  if (iterations >= maxIter - 1.0) {
+    color = vec3(0.0, 0.02, 0.01) + 0.03 * sin(uTime * vec3(0.7, 1.1, 0.9));
+  }
+
+  gl_FragColor = vec4(color, 1.0);
+}
+`;
+
+/** Minimal vertex shader — just pass through */
+const FRACTAL_VERT = `
+precision mediump float;
+attribute vec2 inPosition;
+void main() {
+  gl_Position = vec4(inPosition, 0.0, 1.0);
+}
+`;
+
+export class FractalScene extends Phaser.Scene {
+  private meta!: MetaState;
+  private runState!: RunState;
+  private elapsed = 0;
+  private duration = 12000; // 12 seconds default
+  private shaderEnabled = false;
+  private customPipeline: Phaser.Renderer.WebGL.WebGLPipeline | null = null;
+  private isRenewal = false;
+  private previousCycle = 1;
+
+  // Fallback canvas animation state
+  private fallbackGraphics!: Phaser.GameObjects.Graphics;
+  private fallbackParticles: { x: number; y: number; r: number; angle: number; speed: number; color: number }[] = [];
+
+  constructor() {
+    super({ key: 'FractalScene' });
+  }
+
+  init(data: { meta: MetaState; runState: RunState }): void {
+    this.meta = data.meta;
+    this.runState = data.runState;
+    this.elapsed = 0;
+
+    // More discoveries → longer fractal (reward for exploration)
+    const discCount = this.runState.discoveries.elements.size
+      + this.runState.discoveries.reactions.size
+      + this.runState.discoveries.compounds.size
+      + this.runState.discoveries.creatures.size;
+    this.duration = Math.min(25000, 10000 + discCount * 1000);
+  }
+
+  create(): void {
+    this.cameras.main.setBackgroundColor('#000000');
+
+    // Apply run results to meta and save; check for Great Renewal
+    this.previousCycle = this.meta.greatCycle.cycleNumber;
+    this.isRenewal = applyRunResults(this.meta, this.runState);
+    saveMetaState(this.meta).catch(() => {
+      // Silently fail — game continues even if persistence fails
+    });
+
+    // Try to create WebGL shader
+    this.shaderEnabled = this.tryCreateShader();
+
+    if (!this.shaderEnabled) {
+      this.createFallbackAnimation();
+    }
+
+    // "Spores earned" text (appears after a moment)
+    const sporesText = this.add.text(GAME_WIDTH / 2, GAME_HEIGHT - 60,
+      `+${this.meta.runHistory[this.meta.runHistory.length - 1]?.sporesEarned ?? 0} спор`, {
+        fontSize: '16px',
+        color: '#00ff88',
+        fontFamily: 'monospace',
+      });
+    sporesText.setOrigin(0.5);
+    sporesText.setAlpha(0);
+    sporesText.setDepth(100);
+
+    this.tweens.add({
+      targets: sporesText,
+      alpha: 0.8,
+      duration: 1000,
+      delay: 3000,
+      onComplete: () => {
+        this.tweens.add({
+          targets: sporesText,
+          alpha: 0,
+          duration: 2000,
+          delay: 3000,
+        });
+      },
+    });
+
+    // Skip hint
+    const skipText = this.add.text(GAME_WIDTH / 2, GAME_HEIGHT - 25,
+      '[ click to skip ]', {
+        fontSize: '10px',
+        color: '#333333',
+        fontFamily: 'monospace',
+      });
+    skipText.setOrigin(0.5);
+    skipText.setDepth(100);
+
+    // Click to skip (after minimum 3 seconds)
+    this.input.on('pointerdown', () => {
+      if (this.elapsed > 3000) {
+        this.transitionToCradle();
+      }
+    });
+  }
+
+  private tryCreateShader(): boolean {
+    try {
+      const renderer = this.renderer;
+      if (!(renderer instanceof Phaser.Renderer.WebGL.WebGLRenderer)) {
+        return false;
+      }
+
+      // Use Phaser's shader support via a fullscreen quad
+      const baseShader = new Phaser.Display.BaseShader(
+        'fractal',
+        FRACTAL_FRAG,
+        FRACTAL_VERT,
+        {
+          uTime: { type: '1f', value: 0.0 },
+          uResolution: { type: '2f', value: { x: GAME_WIDTH, y: GAME_HEIGHT } },
+          uZoom: { type: '1f', value: 0.5 },
+          uCenter: { type: '2f', value: { x: -0.5, y: 0.0 } },
+          uMorphFactor: { type: '1f', value: 0.0 },
+        },
+      );
+
+      const shader = this.add.shader(baseShader, GAME_WIDTH / 2, GAME_HEIGHT / 2, GAME_WIDTH, GAME_HEIGHT);
+      shader.setDepth(0);
+
+      return true;
+    } catch {
+      return false;
+    }
+  }
+
+  private createFallbackAnimation(): void {
+    // Canvas-based fractal-ish animation as fallback
+    this.fallbackGraphics = this.add.graphics();
+    this.fallbackParticles = [];
+
+    for (let i = 0; i < 200; i++) {
+      const angle = Math.random() * Math.PI * 2;
+      const dist = 20 + Math.random() * 300;
+      this.fallbackParticles.push({
+        x: GAME_WIDTH / 2 + Math.cos(angle) * dist,
+        y: GAME_HEIGHT / 2 + Math.sin(angle) * dist,
+        r: 1 + Math.random() * 4,
+        angle,
+        speed: 0.2 + Math.random() * 0.8,
+        color: Phaser.Display.Color.HSLToColor(
+          0.3 + Math.random() * 0.3,
+          0.6,
+          0.3 + Math.random() * 0.3,
+        ).color,
+      });
+    }
+  }
+
+  update(_time: number, delta: number): void {
+    this.elapsed += delta;
+
+    if (this.shaderEnabled) {
+      // Update shader uniforms via the shader game object
+      const shaders = this.children.list.filter(
+        (child): child is Phaser.GameObjects.Shader => child instanceof Phaser.GameObjects.Shader,
+      );
+      if (shaders.length > 0) {
+        const shader = shaders[0];
+        const t = this.elapsed / 1000;
+
+        shader.setUniform('uTime.value', t);
+
+        // Slowly zoom in
+        const zoom = 0.5 + t * 0.03;
+        shader.setUniform('uZoom.value', zoom);
+
+        // Slowly morph from Mandelbrot to Julia
+        const morph = Math.min(1.0, t / (this.duration / 1000) * 2);
+        shader.setUniform('uMorphFactor.value', morph);
+
+        // Pan slowly
+        shader.setUniform('uCenter.value.x', -0.5 + Math.sin(t * 0.05) * 0.2);
+        shader.setUniform('uCenter.value.y', Math.cos(t * 0.07) * 0.15);
+      }
+    } else {
+      // Fallback animation
+      this.updateFallbackAnimation(delta);
+    }
+
+    // Auto-transition after duration
+    if (this.elapsed >= this.duration) {
+      this.transitionToCradle();
+    }
+  }
+
+  private updateFallbackAnimation(delta: number): void {
+    if (!this.fallbackGraphics) return;
+
+    this.fallbackGraphics.clear();
+    const cx = GAME_WIDTH / 2;
+    const cy = GAME_HEIGHT / 2;
+    const t = this.elapsed / 1000;
+
+    for (const p of this.fallbackParticles) {
+      // Spiral motion
+      p.angle += p.speed * (delta / 1000);
+      const dist = 50 + Math.sin(t * 0.5 + p.angle * 3) * 100 + Math.cos(t * 0.3) * 50;
+      p.x = cx + Math.cos(p.angle) * dist;
+      p.y = cy + Math.sin(p.angle) * dist;
+
+      const alpha = 0.3 + Math.sin(t + p.angle * 2) * 0.3;
+      this.fallbackGraphics.fillStyle(p.color, Math.max(0.05, alpha));
+      this.fallbackGraphics.fillCircle(p.x, p.y, p.r);
+
+      // Connect nearby particles with dim lines
+      if (Math.random() < 0.02) {
+        const other = this.fallbackParticles[Math.floor(Math.random() * this.fallbackParticles.length)];
+        this.fallbackGraphics.lineStyle(1, 0x00ff88, 0.05);
+        this.fallbackGraphics.beginPath();
+        this.fallbackGraphics.moveTo(p.x, p.y);
+        this.fallbackGraphics.lineTo(other.x, other.y);
+        this.fallbackGraphics.strokePath();
+      }
+    }
+  }
+
+  private transitionToCradle(): void {
+    // Prevent double-transition
+    if ((this as unknown as { _transitioning?: boolean })._transitioning) return;
+    (this as unknown as { _transitioning?: boolean })._transitioning = true;
+
+    this.cameras.main.fadeOut(1500, 0, 0, 0);
+    this.cameras.main.once('camerafadeoutcomplete', () => {
+      if (this.isRenewal) {
+        // Great Renewal — show special scene before returning to Cradle
+        this.scene.start('RenewalScene', {
+          meta: this.meta,
+          previousCycle: this.previousCycle,
+        });
+      } else {
+        this.scene.start('CradleScene', { meta: this.meta });
+      }
+    });
+  }
+}

src/scenes/GameScene.ts

@@ -1,50 +1,264 @@
 import Phaser from 'phaser';
 import { createGameWorld, updateTime, type GameWorld } from '../ecs/world';
+import { Health, Position, Creature, LifeCycle } from '../ecs/components';
 import { movementSystem } from '../ecs/systems/movement';
 import { healthSystem } from '../ecs/systems/health';
 import { removeGameEntity } from '../ecs/factory';
 import { PhaserBridge } from '../ecs/bridge';
 import biomeDataArray from '../data/biomes.json';
+import speciesDataArray from '../data/creatures.json';
+import schoolsData from '../data/schools.json';
 import type { BiomeData } from '../world/types';
 import { generateWorld } from '../world/generator';
 import { createWorldTilemap } from '../world/tilemap';
-import { setupCamera, updateCamera, type CameraKeys } from '../world/camera';
+import { setupPlayerCamera } from '../world/camera';
 import { Minimap } from '../world/minimap';
+import { playerInputSystem } from '../player/input';
+import { tileCollisionSystem, buildWalkableSet } from '../player/collision';
+import { findSpawnPosition } from '../player/spawn';
+import { createPlayerEntity } from '../player/factory';
+import { Inventory } from '../player/inventory';
+import { interactionSystem, type ResourceInfo } from '../player/interaction';
+import { spawnResources } from '../world/resources';
+import {
+  launchProjectile,
+  projectileSystem,
+  type ProjectileData,
+} from '../player/projectile';
+import { QuickSlots } from '../player/quickslots';
+import type { InputState } from '../player/types';
+import type { SpeciesData, CreatureInfo } from '../creatures/types';
+import { SpeciesRegistry } from '../creatures/types';
+import { aiSystem } from '../creatures/ai';
+import { metabolismSystem, clearMetabolismTracking } from '../creatures/metabolism';
+import { lifeCycleSystem } from '../creatures/lifecycle';
+import {
+  countPopulations,
+  spawnInitialCreatures,
+  reproduce,
+} from '../creatures/population';
+import {
+  creatureProjectileSystem,
+  getObservableCreatures,
+  creatureAttackPlayerSystem,
+} from '../creatures/interaction';
+import { query } from 'bitecs';
+
+// Run cycle imports
+import type { MetaState, SchoolData, RunState, ResolvedSchoolBonuses } from '../run/types';
+import { RunPhase, RUN_PHASE_NAMES_RU, PHASE_DURATIONS } from '../run/types';
+import { getSchoolBonuses } from '../run/meta';
+import { createRunState, advancePhase, updateEscalation, recordDiscovery } from '../run/state';
+import {
+  createCrisisState,
+  applyCrisisDamage,
+  attemptNeutralize,
+  getCrisisPlayerDamage,
+  getCrisisTint,
+  CHEMICAL_PLAGUE,
+  type CrisisState,
+} from '../run/crisis';
+import { getEscalationEffects } from '../run/escalation';
+
+// UI zoom compensation
+import { fixToScreen } from '../ui/screen-fix';
+
+// Mycelium imports
+import { FungalNode } from '../ecs/components';
+import { spawnFungalNodes } from '../mycelium/nodes';
+import { depositKnowledge } from '../mycelium/graph';
+import { extractMemoryFlashes } from '../mycelium/knowledge';
+import { createMycosisState, updateMycosis, getMycosisVisuals } from '../mycelium/mycosis';
+import type { FungalNodeInfo, MycosisState, MemoryFlash } from '../mycelium/types';
+import { FUNGAL_NODE_CONFIG, MYCOSIS_CONFIG } from '../mycelium/types';
+
+// World traces (Great Cycle)
+import { spawnWorldTraces, updateTraceGlow, type WorldTraceInfo } from '../world/traces';
+import { CYCLE_THEME_NAMES_RU } from '../run/types';
 
 export class GameScene extends Phaser.Scene {
   private gameWorld!: GameWorld;
   private bridge!: PhaserBridge;
-  private cameraKeys!: CameraKeys;
   private minimap!: Minimap;
   private statsText!: Phaser.GameObjects.Text;
   private worldSeed!: number;
 
+  // Player state
+  private playerEid!: number;
+  private inventory!: Inventory;
+  private walkableSet!: Set<number>;
+  private worldGrid!: number[][];
+  private tileSize!: number;
+  private resourceData!: Map<number, ResourceInfo>;
+  private projectileData!: Map<number, ProjectileData>;
+  private quickSlots!: QuickSlots;
+  private keys!: {
+    W: Phaser.Input.Keyboard.Key;
+    A: Phaser.Input.Keyboard.Key;
+    S: Phaser.Input.Keyboard.Key;
+    D: Phaser.Input.Keyboard.Key;
+    E: Phaser.Input.Keyboard.Key;
+    F: Phaser.Input.Keyboard.Key;
+    ONE: Phaser.Input.Keyboard.Key;
+    TWO: Phaser.Input.Keyboard.Key;
+    THREE: Phaser.Input.Keyboard.Key;
+    FOUR: Phaser.Input.Keyboard.Key;
+  };
+
+  // Creature state
+  private speciesRegistry!: SpeciesRegistry;
+  private speciesLookup!: Map<number, SpeciesData>;
+  private creatureData!: Map<number, CreatureInfo>;
+
+  // Interaction feedback
+  private interactionText!: Phaser.GameObjects.Text;
+  private interactionTimer = 0;
+  private wasEDown = false;
+  private wasFDown = false;
+
+  // Run cycle state
+  private meta!: MetaState;
+  private runState!: RunState;
+  private crisisState: CrisisState | null = null;
+  private phaseText!: Phaser.GameObjects.Text;
+  private playerDead = false;
+  private crisisOverlay!: Phaser.GameObjects.Rectangle;
+
+  // Mycelium state
+  private fungalNodeData!: Map<number, FungalNodeInfo>;
+  private mycosisState!: MycosisState;
+  private mycosisOverlay!: Phaser.GameObjects.Rectangle;
+  private memoryFlashText!: Phaser.GameObjects.Text;
+  private memoryFlashTimer = 0;
+  private fungalNodeGlowGraphics!: Phaser.GameObjects.Graphics;
+  private hasDepositedThisRun = false;
+
+  // World traces from past runs
+  private worldTraceData: WorldTraceInfo[] = [];
+  private worldTraceGraphics!: Phaser.GameObjects.Graphics;
+
   constructor() {
     super({ key: 'GameScene' });
   }
 
+  // Purchased bonuses from Cradle shop
+  private purchasedEffects: import('../mycelium/types').BonusEffect[] = [];
+
+  // Biome selection
+  private biomeId = 'catalytic-wastes';
+
+  // School bonuses (resolved from school data)
+  private schoolBonuses!: ResolvedSchoolBonuses;
+
+  init(data: { meta: MetaState; schoolId: string; runId: number; purchasedEffects?: import('../mycelium/types').BonusEffect[]; biomeId?: string }): void {
+    this.meta = data.meta;
+    this.biomeId = data.biomeId ?? 'catalytic-wastes';
+    this.runState = createRunState(data.runId, data.schoolId, this.biomeId);
+    this.crisisState = null;
+    this.playerDead = false;
+    this.mycosisState = createMycosisState();
+    this.hasDepositedThisRun = false;
+    this.memoryFlashTimer = 0;
+    this.purchasedEffects = data.purchasedEffects ?? [];
+    this.schoolBonuses = getSchoolBonuses(data.schoolId);
+  }
+
   create(): void {
-    // 1. Initialize ECS (needed for future entity systems)
+    // 1. Initialize ECS
     this.gameWorld = createGameWorld();
     this.bridge = new PhaserBridge(this);
+    this.projectileData = new Map();
 
-    // 2. Generate world
+    // 2. Generate world — use selected biome
-    const biome = biomeDataArray[0] as BiomeData;
+    const biome = (biomeDataArray as BiomeData[]).find(b => b.id === this.biomeId) ?? biomeDataArray[0] as BiomeData;
     this.worldSeed = Date.now() % 1000000;
+    this.runState.worldSeed = this.worldSeed;
     const worldData = generateWorld(biome, this.worldSeed);
 
     // 3. Create tilemap
     createWorldTilemap(this, worldData);
 
-    // 4. Camera with bounds and WASD controls
+    // 4. Build walkable set + store world data for collision
+    this.walkableSet = buildWalkableSet(biome.tiles);
+    this.worldGrid = worldData.grid;
+    this.tileSize = biome.tileSize;
+
+    // 5. Spawn resource entities (mineral veins, geysers)
+    this.resourceData = spawnResources(
+      this.gameWorld.world, worldData.grid, biome, this.worldSeed,
+    );
+
+    // 5b. Spawn fungal nodes (Mycelium surface points)
+    this.fungalNodeData = spawnFungalNodes(
+      this.gameWorld.world, worldData.grid, biome, this.worldSeed,
+    );
+
+    // 5c. Spawn world traces from past runs (Great Cycle)
+    this.worldTraceData = spawnWorldTraces(
+      this.gameWorld.world, this.meta.greatCycle, this.biomeId, biome,
+    );
+    this.worldTraceGraphics = this.add.graphics();
+    this.worldTraceGraphics.setDepth(4); // above tiles, below entities
+
+    // 6. Initialize creature systems — filter by biome
+    const allSpecies = speciesDataArray as SpeciesData[];
+    const biomeSpecies = allSpecies.filter(s => s.biome === biome.id);
+    this.speciesRegistry = new SpeciesRegistry(biomeSpecies);
+    this.speciesLookup = new Map<number, SpeciesData>();
+    for (const s of biomeSpecies) {
+      this.speciesLookup.set(s.speciesId, s);
+    }
+
+    // 7. Spawn creatures across the map
+    this.creatureData = spawnInitialCreatures(
+      this.gameWorld.world, worldData.grid, biome, this.worldSeed, biomeSpecies,
+    );
+
+    // 8. Create player at spawn position + inventory with starting kit
+    const spawn = findSpawnPosition(worldData.grid, biome.tileSize, this.walkableSet);
+    const spawnX = spawn?.x ?? (biome.mapWidth * biome.tileSize) / 2;
+    const spawnY = spawn?.y ?? (biome.mapHeight * biome.tileSize) / 2;
+    this.playerEid = createPlayerEntity(this.gameWorld.world, spawnX, spawnY);
+    this.inventory = new Inventory(500, 20);
+    this.quickSlots = new QuickSlots();
+
+    // Give starting elements from chosen school + apply purchased bonuses
+    this.giveStartingKit();
+    this.applyPurchasedEffects();
+
+    // 9. Camera — follow player, zoom via scroll wheel
     const worldPixelW = biome.mapWidth * biome.tileSize;
     const worldPixelH = biome.mapHeight * biome.tileSize;
-    this.cameraKeys = setupCamera(this, worldPixelW, worldPixelH);
+    setupPlayerCamera(this, worldPixelW, worldPixelH);
 
-    // 5. Minimap
+    // Sync bridge to create sprites, then attach camera follow to player
+    this.bridge.sync(this.gameWorld.world);
+    const playerSprite = this.bridge.getSprite(this.playerEid);
+    if (playerSprite) {
+      playerSprite.setDepth(10);
+      this.cameras.main.startFollow(playerSprite, true, 0.1, 0.1);
+    }
+
+    // 8. Keyboard input
+    const keyboard = this.input.keyboard;
+    if (!keyboard) throw new Error('Keyboard plugin not available');
+    this.keys = {
+      W: keyboard.addKey('W'),
+      A: keyboard.addKey('A'),
+      S: keyboard.addKey('S'),
+      D: keyboard.addKey('D'),
+      E: keyboard.addKey('E'),
+      F: keyboard.addKey('F'),
+      ONE: keyboard.addKey(Phaser.Input.Keyboard.KeyCodes.ONE),
+      TWO: keyboard.addKey(Phaser.Input.Keyboard.KeyCodes.TWO),
+      THREE: keyboard.addKey(Phaser.Input.Keyboard.KeyCodes.THREE),
+      FOUR: keyboard.addKey(Phaser.Input.Keyboard.KeyCodes.FOUR),
+    };
+
+    // 9. Minimap
     this.minimap = new Minimap(this, worldData);
 
-    // 6. UI overlay
+    // 10. UI overlay
     this.statsText = this.add.text(10, 10, '', {
       fontSize: '12px',
       color: '#00ff88',
@@ -54,30 +268,707 @@ export class GameScene extends Phaser.Scene {
     });
     this.statsText.setScrollFactor(0);
     this.statsText.setDepth(100);
+
+    // Interaction feedback text (center-bottom of screen)
+    this.interactionText = this.add.text(
+      this.cameras.main.width / 2, this.cameras.main.height - 40, '', {
+        fontSize: '14px',
+        color: '#ffdd44',
+        fontFamily: 'monospace',
+        backgroundColor: '#000000cc',
+        padding: { x: 6, y: 3 },
+      },
+    );
+    this.interactionText.setScrollFactor(0);
+    this.interactionText.setOrigin(0.5);
+    this.interactionText.setDepth(100);
+    this.interactionText.setAlpha(0);
+
+    // Phase indicator (top-center)
+    this.phaseText = this.add.text(
+      this.cameras.main.width / 2, 12, '', {
+        fontSize: '12px',
+        color: '#00ff88',
+        fontFamily: 'monospace',
+        backgroundColor: '#000000aa',
+        padding: { x: 6, y: 2 },
+      },
+    );
+    this.phaseText.setScrollFactor(0);
+    this.phaseText.setOrigin(0.5, 0);
+    this.phaseText.setDepth(100);
+
+    // Crisis overlay (full-screen tinted rectangle, hidden by default)
+    this.crisisOverlay = this.add.rectangle(
+      this.cameras.main.width / 2, this.cameras.main.height / 2,
+      this.cameras.main.width, this.cameras.main.height,
+      0x88ff88, 0,
+    );
+    this.crisisOverlay.setScrollFactor(0);
+    this.crisisOverlay.setDepth(90);
+
+    // 10b. Mycosis overlay (full-screen tinted rectangle, hidden by default)
+    this.mycosisOverlay = this.add.rectangle(
+      this.cameras.main.width / 2, this.cameras.main.height / 2,
+      this.cameras.main.width, this.cameras.main.height,
+      MYCOSIS_CONFIG.tintColor, 0,
+    );
+    this.mycosisOverlay.setScrollFactor(0);
+    this.mycosisOverlay.setDepth(91);
+
+    // 10c. Fungal node glow graphics (world-space, under entities)
+    this.fungalNodeGlowGraphics = this.add.graphics();
+    this.fungalNodeGlowGraphics.setDepth(2);
+
+    // 10d. Memory flash text (center of screen, fades in/out)
+    this.memoryFlashText = this.add.text(
+      this.cameras.main.width / 2, this.cameras.main.height / 2, '', {
+        fontSize: '16px',
+        color: '#88ffaa',
+        fontFamily: 'monospace',
+        backgroundColor: '#0a1a0fcc',
+        padding: { x: 12, y: 8 },
+        align: 'center',
+        wordWrap: { width: 400 },
+      },
+    );
+    this.memoryFlashText.setScrollFactor(0);
+    this.memoryFlashText.setOrigin(0.5);
+    this.memoryFlashText.setDepth(105);
+    this.memoryFlashText.setAlpha(0);
+
+    // 11. Launch UIScene overlay
+    this.scene.launch('UIScene');
+
+      // Transition from Awakening to Exploration after a moment
+    this.time.delayedCall(500, () => {
+      advancePhase(this.runState); // Awakening → Exploration
+    });
+
+    // Debug: expose kill method for testing death cycle
+    (this as unknown as Record<string, unknown>).__debugKill = () => {
+      Health.current[this.playerEid] = 0;
+    };
+  }
+
+  /** Apply purchased spore bonuses from the Cradle shop */
+  private applyPurchasedEffects(): void {
+    for (const effect of this.purchasedEffects) {
+      switch (effect.type) {
+        case 'extra_health':
+          Health.max[this.playerEid] = (Health.max[this.playerEid] ?? 100) + effect.amount;
+          Health.current[this.playerEid] = Health.max[this.playerEid];
+          break;
+        case 'extra_element':
+          for (let i = 0; i < effect.quantity; i++) {
+            this.inventory.addItem(effect.symbol);
+          }
+          this.quickSlots.autoAssign(effect.symbol);
+          break;
+        case 'knowledge_boost':
+          // Stored for use when extracting memory flashes
+          // (increases clarity of extracted flashes)
+          break;
+      }
+    }
+  }
+
+  /** Give the player their school's starting elements */
+  private giveStartingKit(): void {
+    const schools = schoolsData as unknown as SchoolData[];
+    const school = schools.find(s => s.id === this.runState.schoolId);
+    if (!school) return;
+
+    for (const symbol of school.startingElements) {
+      const qty = school.startingQuantities[symbol] ?? 1;
+      for (let i = 0; i < qty; i++) {
+        this.inventory.addItem(symbol);
+      }
+      this.quickSlots.autoAssign(symbol);
+
+      // Record discovery of starting elements
+      recordDiscovery(this.runState, 'element', symbol);
+    }
   }
 
   update(_time: number, delta: number): void {
+    // Skip updates if death transition is in progress
+    if (this.playerDead) return;
+
     // 1. Update world time
     updateTime(this.gameWorld, delta);
 
-    // 2. Camera movement
+    // 1a. Update run state timers
-    updateCamera(this, this.cameraKeys, delta);
+    this.runState.elapsed += delta;
+    this.runState.phaseTimer += delta;
+    this.updateRunPhase(delta);
 
-    // 3. ECS systems (no entities yet — future phases will add player, creatures)
+    // 2. Read keyboard → InputState
+    const input: InputState = {
+      moveX: (this.keys.D.isDown ? 1 : 0) - (this.keys.A.isDown ? 1 : 0),
+      moveY: (this.keys.S.isDown ? 1 : 0) - (this.keys.W.isDown ? 1 : 0),
+      interact: this.keys.E.isDown,
+    };
+
+    // 3. Player input → velocity (Navigator school gets speed bonus)
+    playerInputSystem(this.gameWorld.world, input, this.schoolBonuses.movementSpeed);
+
+    // 4. Movement (all entities including projectiles)
     movementSystem(this.gameWorld.world, delta);
-    const dead = healthSystem(this.gameWorld.world);
+
-    for (const eid of dead) {
+    // 5. Tile collision (player only)
-      removeGameEntity(this.gameWorld.world, eid);
+    tileCollisionSystem(
+      this.gameWorld.world,
+      delta,
+      this.worldGrid,
+      this.tileSize,
+      this.walkableSet,
+    );
+
+    // 6. Projectile system (lifetime + tile collision)
+    projectileSystem(
+      this.gameWorld.world,
+      delta,
+      this.worldGrid,
+      this.tileSize,
+      this.walkableSet,
+      this.projectileData,
+    );
+
+    // 7. E key interaction (debounced) — fungal node has priority, then resources
+    const isEDown = this.keys.E.isDown;
+    const justPressedE = isEDown && !this.wasEDown;
+    this.wasEDown = isEDown;
+
+    // Check if player is near a fungal node first
+    const nearbyFungalNode = this.getNearestFungalNode();
+    if (justPressedE && nearbyFungalNode !== null) {
+      // Fungal node interaction takes priority
+      this.interactWithFungalNode(nearbyFungalNode);
+    } else {
+      // Normal resource interaction
+      const interaction = interactionSystem(
+        this.gameWorld.world, justPressedE, this.inventory, this.resourceData,
+      );
+      if (interaction) {
+        if (interaction.type === 'collected' || interaction.type === 'depleted') {
+          if (interaction.itemId) {
+            this.quickSlots.autoAssign(interaction.itemId);
+            recordDiscovery(this.runState, 'element', interaction.itemId);
+          }
+        }
+        this.showInteractionFeedback(interaction.type, interaction.itemId);
+      }
     }
-    this.bridge.sync(this.gameWorld.world);
 
-    // 4. Minimap viewport
+    // 8. Quick slot selection (1-4 keys)
-    this.minimap.update(this.cameras.main);
+    if (this.keys.ONE.isDown) this.quickSlots.setActive(0);
+    if (this.keys.TWO.isDown) this.quickSlots.setActive(1);
+    if (this.keys.THREE.isDown) this.quickSlots.setActive(2);
+    if (this.keys.FOUR.isDown) this.quickSlots.setActive(3);
 
-    // 5. Stats
+    // 9. Throw projectile (F key, debounced) — uses active quick slot
-    const fps = delta > 0 ? Math.round(1000 / delta) : 0;
+    const isFDown = this.keys.F.isDown;
-    this.statsText.setText(
+    const justPressedF = isFDown && !this.wasFDown;
-      `seed: ${this.worldSeed} | ${fps} fps | WASD move, scroll zoom`,
+    this.wasFDown = isFDown;
+    if (justPressedF) {
+      this.tryLaunchProjectile();
+    }
+
+    // 9a. Creature AI — aggro range affected by Naturalist school bonus
+    aiSystem(
+      this.gameWorld.world, delta,
+      this.speciesLookup, this.gameWorld.time.tick,
+      this.schoolBonuses.creatureAggroRange,
+    );
+
+    // 9b. Creature metabolism (feeding, energy drain)
+    metabolismSystem(
+      this.gameWorld.world, delta,
+      this.resourceData, this.gameWorld.time.elapsed,
+    );
+
+    // 9c. Creature life cycle (aging, stage transitions)
+    const lcEvents = lifeCycleSystem(
+      this.gameWorld.world, delta, this.speciesLookup,
+    );
+
+    // 9d. Handle reproduction events
+    const populations = countPopulations(this.gameWorld.world);
+    for (const event of lcEvents) {
+      if (event.type === 'ready_to_reproduce') {
+        const species = this.speciesLookup.get(event.speciesId);
+        if (species) {
+          const currentPop = populations.get(event.speciesId) ?? 0;
+          reproduce(
+            this.gameWorld.world, event.eid, species,
+            currentPop, this.creatureData,
           );
         }
       }
+    }
+
+    // 9e. Projectile-creature collision (Mechanic school gets damage bonus)
+    creatureProjectileSystem(
+      this.gameWorld.world, this.projectileData, this.speciesLookup,
+      this.schoolBonuses.projectileDamage,
+    );
+
+    // 9f. Creature attacks on player
+    creatureAttackPlayerSystem(this.gameWorld.world, this.speciesLookup);
+
+    // 9g. Mycelium — fungal node glow, interaction, mycosis
+    this.updateMycelium(delta);
+
+    // 9h. Crisis damage (if active)
+    if (this.crisisState?.active) {
+      applyCrisisDamage(this.crisisState, delta);
+      const crisisDmg = getCrisisPlayerDamage(this.crisisState, delta);
+      if (crisisDmg > 0) {
+        Health.current[this.playerEid] = Math.max(
+          0,
+          (Health.current[this.playerEid] ?? 0) - crisisDmg,
+        );
+      }
+      // Update crisis visual tint
+      const tint = getCrisisTint(this.crisisState);
+      this.crisisOverlay.setFillStyle(tint.color, tint.alpha);
+    }
+
+    // 9i. Environmental damage from high escalation
+    const escalationFx = getEscalationEffects(this.runState.escalation);
+    if (escalationFx.environmentalDamage > 0) {
+      const envDmg = escalationFx.environmentalDamage * (delta / 1000);
+      Health.current[this.playerEid] = Math.max(
+        0,
+        (Health.current[this.playerEid] ?? 0) - envDmg,
+      );
+    }
+
+    // 10. Health / death
+    const dead = healthSystem(this.gameWorld.world);
+    let playerDied = false;
+    for (const eid of dead) {
+      if (eid === this.playerEid) {
+        playerDied = true;
+        continue; // Don't remove player entity yet
+      }
+      // Clean up creature tracking
+      if (this.creatureData.has(eid)) {
+        clearMetabolismTracking(eid);
+        this.creatureData.delete(eid);
+      }
+      removeGameEntity(this.gameWorld.world, eid);
+    }
+
+    // Handle player death → transition to DeathScene
+    if (playerDied) {
+      this.onPlayerDeath();
+      return;
+    }
+
+    // 10. Render sync
+    this.bridge.sync(this.gameWorld.world);
+
+    // 11. Minimap viewport
+    this.minimap.update(this.cameras.main);
+
+    // 12. Fade interaction text
+    if (this.interactionTimer > 0) {
+      this.interactionTimer -= delta;
+      if (this.interactionTimer <= 0) {
+        this.interactionText.setAlpha(0);
+      }
+    }
+
+    // 13. Push shared state to registry for UIScene
+    this.registry.set('health', Health.current[this.playerEid] ?? 100);
+    this.registry.set('healthMax', Health.max[this.playerEid] ?? 100);
+    this.registry.set('quickSlots', this.quickSlots.getAll());
+    this.registry.set('activeSlot', this.quickSlots.activeIndex);
+    this.registry.set('invWeight', this.inventory.getTotalWeight());
+    this.registry.set('invMaxWeight', this.inventory.maxWeight);
+    this.registry.set('invSlots', this.inventory.slotCount);
+
+    // Build counts map for UIScene
+    const counts = new Map<string, number>();
+    for (const item of this.inventory.getItems()) {
+      counts.set(item.id, item.count);
+    }
+    this.registry.set('invCounts', counts);
+
+    // 14. Push cycle info to registry for UIScene
+    this.registry.set('cycleNumber', this.meta.greatCycle.cycleNumber);
+    this.registry.set('runInCycle', this.meta.greatCycle.runInCycle);
+    this.registry.set('cycleThemeRu', CYCLE_THEME_NAMES_RU[this.meta.greatCycle.theme]);
+    this.registry.set('runPhaseRu', RUN_PHASE_NAMES_RU[this.runState.phase]);
+
+    // 15. Creature observation for UIScene
+    const nearbyCreatures = getObservableCreatures(this.gameWorld.world);
+    if (nearbyCreatures.length > 0) {
+      const closest = nearbyCreatures[0];
+      const species = this.speciesLookup.get(closest.speciesId);
+      this.registry.set('observedCreature', {
+        name: species?.name ?? 'Unknown',
+        healthPercent: closest.healthPercent,
+        energyPercent: closest.energyPercent,
+        stage: closest.stage,
+      });
+      // Record creature observation as discovery
+      if (species) {
+        recordDiscovery(this.runState, 'creature', species.id);
+      }
+    } else {
+      this.registry.set('observedCreature', null);
+    }
+
+    // 16. Population counts for debug
+    const popCounts = countPopulations(this.gameWorld.world);
+    this.registry.set('creaturePopulations', popCounts);
+
+    // 17. Debug stats overlay + phase indicator
+    const fps = delta > 0 ? Math.round(1000 / delta) : 0;
+    const px = Math.round(Position.x[this.playerEid]);
+    const py = Math.round(Position.y[this.playerEid]);
+    const creatureCount = [...popCounts.values()].reduce((a, b) => a + b, 0);
+    this.statsText.setText(
+      `seed: ${this.worldSeed} | ${fps} fps | pos: ${px},${py} | creatures: ${creatureCount}`,
+    );
+
+    // Update phase indicator
+    const phaseName = RUN_PHASE_NAMES_RU[this.runState.phase];
+    const escalationPct = Math.round(this.runState.escalation * 100);
+    const crisisInfo = this.crisisState?.active
+      ? ` | ☠ ЧУМА: ${Math.round(this.crisisState.progress * 100)}%`
+      : this.runState.crisisResolved ? ' | ✓ Чума нейтрализована' : '';
+    const escFx = getEscalationEffects(this.runState.escalation);
+    const speedInfo = escFx.creatureSpeedMultiplier > 1.05
+      ? ` | Агрессия: ×${escFx.creatureAttackMultiplier.toFixed(1)}`
+      : '';
+    this.phaseText.setText(`${phaseName} | Энтропия: ${escalationPct}%${speedInfo}${crisisInfo}`);
+
+    // Color phase text based on danger
+    if (this.runState.phase >= RunPhase.Crisis) {
+      this.phaseText.setColor('#ff4444');
+    } else if (this.runState.phase >= RunPhase.Escalation) {
+      this.phaseText.setColor('#ffaa00');
+    } else {
+      this.phaseText.setColor('#00ff88');
+    }
+
+    // Fix UI element positions for current camera zoom.
+    // setScrollFactor(0) prevents scroll but NOT zoom displacement.
+    const cam = this.cameras.main;
+    fixToScreen(this.statsText, 10, 30, cam);
+    fixToScreen(this.interactionText, cam.width / 2, cam.height - 40, cam);
+    fixToScreen(this.phaseText, cam.width / 2, 12, cam);
+    fixToScreen(this.memoryFlashText, cam.width / 2, cam.height / 2, cam);
+    fixToScreen(this.crisisOverlay, cam.width / 2, cam.height / 2, cam);
+    fixToScreen(this.mycosisOverlay, cam.width / 2, cam.height / 2, cam);
+  }
+
+  /** Find the nearest fungal node within interaction range, or null */
+  private getNearestFungalNode(): number | null {
+    const px = Position.x[this.playerEid];
+    const py = Position.y[this.playerEid];
+    const nodeEids = query(this.gameWorld.world, [Position, FungalNode]);
+
+    let nearestEid: number | null = null;
+    let nearestDist = Infinity;
+
+    for (const eid of nodeEids) {
+      const dx = Position.x[eid] - px;
+      const dy = Position.y[eid] - py;
+      const dist = Math.sqrt(dx * dx + dy * dy);
+      if (dist <= FungalNode.interactRange[eid] && dist < nearestDist) {
+        nearestEid = eid;
+        nearestDist = dist;
+      }
+    }
+
+    return nearestEid;
+  }
+
+  /** Mycelium system — glow animation, mycosis update, memory flash fade */
+  private updateMycelium(delta: number): void {
+    // Check proximity to any fungal node (for mycosis)
+    const nearNode = this.getNearestFungalNode() !== null;
+
+    // Update mycosis
+    updateMycosis(this.mycosisState, delta, nearNode);
+    const visuals = getMycosisVisuals(this.mycosisState);
+    this.mycosisOverlay.setFillStyle(visuals.tintColor, visuals.tintAlpha);
+
+    // Render fungal node glows
+    const nodeEids = query(this.gameWorld.world, [Position, FungalNode]);
+    this.fungalNodeGlowGraphics.clear();
+    for (const eid of nodeEids) {
+      FungalNode.glowPhase[eid] += FUNGAL_NODE_CONFIG.glowPulseSpeed * (delta / 1000);
+      const phase = FungalNode.glowPhase[eid];
+      const pulse = 0.4 + 0.6 * Math.sin(phase);
+      const radius = FUNGAL_NODE_CONFIG.glowRadius * (0.8 + 0.4 * pulse);
+      const alpha = 0.15 + 0.15 * pulse;
+
+      this.fungalNodeGlowGraphics.fillStyle(FUNGAL_NODE_CONFIG.glowColor, alpha);
+      this.fungalNodeGlowGraphics.fillCircle(
+        Position.x[eid], Position.y[eid], radius,
+      );
+      // Inner brighter glow
+      this.fungalNodeGlowGraphics.fillStyle(FUNGAL_NODE_CONFIG.glowColor, alpha * 1.5);
+      this.fungalNodeGlowGraphics.fillCircle(
+        Position.x[eid], Position.y[eid], radius * 0.5,
+      );
+    }
+
+    // Render world trace glows (past run markers)
+    this.worldTraceGraphics.clear();
+    updateTraceGlow(this.worldTraceData, delta);
+    for (const trace of this.worldTraceData) {
+      const eid = trace.eid;
+      const phase = (this.worldTraceGraphics as unknown as { _phase?: number })._phase ?? 0;
+      const glowPhase = phase + Position.x[eid] * 0.01; // offset per position
+      const pulse = 0.3 + 0.7 * Math.sin(glowPhase + this.runState.elapsed * 0.001);
+      const color = trace.traceType === 'death_site' ? 0xaa3333 : 0x4488aa;
+      const alpha = 0.1 + 0.1 * pulse;
+      const radius = 8 * (0.7 + 0.3 * pulse);
+
+      this.worldTraceGraphics.fillStyle(color, alpha);
+      this.worldTraceGraphics.fillCircle(Position.x[eid], Position.y[eid], radius);
+      // Inner core
+      this.worldTraceGraphics.fillStyle(color, alpha * 2);
+      this.worldTraceGraphics.fillCircle(Position.x[eid], Position.y[eid], radius * 0.4);
+    }
+
+    // Fade memory flash text
+    if (this.memoryFlashTimer > 0) {
+      this.memoryFlashTimer -= delta;
+      if (this.memoryFlashTimer <= 500) {
+        this.memoryFlashText.setAlpha(this.memoryFlashTimer / 500);
+      }
+      if (this.memoryFlashTimer <= 0) {
+        this.memoryFlashText.setAlpha(0);
+      }
+    }
+
+    // Push mycosis data to registry for UIScene
+    this.registry.set('mycosisLevel', this.mycosisState.level);
+    this.registry.set('mycosisRevealing', this.mycosisState.revealing);
+  }
+
+  /** Handle interaction with a fungal node */
+  private interactWithFungalNode(nodeEid: number): void {
+    // First time interacting in this run → deposit discoveries
+    if (!this.hasDepositedThisRun) {
+      const result = depositKnowledge(this.meta.mycelium, this.runState);
+      this.hasDepositedThisRun = true;
+
+      const msg = result.newNodes > 0
+        ? `🍄 Мицелий принял ${result.newNodes} знани${result.newNodes === 1 ? 'е' : 'й'}`
+        : `🍄 Мицелий укрепил ${result.strengthened} связ${result.strengthened === 1 ? 'ь' : 'ей'}`;
+      this.showInteractionFeedback('collected', msg);
+    }
+
+    // Extract memory flashes from past runs
+    if (this.meta.mycelium.nodes.length > 0) {
+      const flashes = extractMemoryFlashes(this.meta.mycelium, 2);
+      if (flashes.length > 0) {
+        this.showMemoryFlash(flashes[0]);
+      }
+    } else {
+      this.showInteractionFeedback('collected', '🍄 Мицелий пуст... пока.');
+    }
+  }
+
+  /** Display a memory flash on screen */
+  private showMemoryFlash(flash: MemoryFlash): void {
+    // Show Russian text with clarity indicator
+    const clarityStars = flash.clarity >= 0.7 ? '★★★' : flash.clarity >= 0.4 ? '★★☆' : '★☆☆';
+    const text = `${flash.textRu}\n\n[${clarityStars}]`;
+    this.memoryFlashText.setText(text);
+    this.memoryFlashText.setAlpha(1);
+    this.memoryFlashTimer = 4000; // Show for 4 seconds
+  }
+
+  /** Manage run phase transitions and escalation */
+  private updateRunPhase(delta: number): void {
+    const phase = this.runState.phase;
+    const timer = this.runState.phaseTimer;
+    const duration = PHASE_DURATIONS[phase];
+
+    // Update escalation
+    updateEscalation(this.runState, delta);
+
+    // Auto-advance timed phases
+    if (duration > 0 && timer >= duration) {
+      if (phase === RunPhase.Exploration) {
+        advancePhase(this.runState); // → Escalation
+      } else if (phase === RunPhase.Escalation) {
+        advancePhase(this.runState); // → Crisis
+        this.triggerCrisis();
+      } else if (phase === RunPhase.Resolution) {
+        // Resolution phase complete → enter boss arena
+        this.enterBossArena();
+      }
+    }
+
+    // Trigger crisis when escalation hits threshold (even before phase ends)
+    if (
+      phase === RunPhase.Escalation &&
+      !this.crisisState &&
+      this.runState.escalation >= CHEMICAL_PLAGUE.triggerThreshold
+    ) {
+      advancePhase(this.runState); // → Crisis
+      this.triggerCrisis();
+    }
+  }
+
+  /** Activate the Chemical Plague crisis */
+  private triggerCrisis(): void {
+    this.crisisState = createCrisisState(CHEMICAL_PLAGUE);
+    this.runState.crisisActive = true;
+
+    this.showInteractionFeedback('collected', '⚠ ХИМИЧЕСКАЯ ЧУМА! Создай CaO для нейтрализации!');
+
+    // Tint the world slightly toxic via overlay
+    this.crisisOverlay.setFillStyle(0x88ff88, 0.08);
+  }
+
+  /** Handle player death — start death sequence */
+  private onPlayerDeath(): void {
+    this.playerDead = true;
+    this.runState.alive = false;
+
+    // Record death position for great cycle traces
+    const px = Position.x[this.playerEid] ?? 0;
+    const py = Position.y[this.playerEid] ?? 0;
+    this.runState.deathPosition = {
+      tileX: Math.floor(px / this.tileSize),
+      tileY: Math.floor(py / this.tileSize),
+    };
+
+    // Auto-deposit all discoveries into Mycelium on death
+    if (!this.hasDepositedThisRun) {
+      depositKnowledge(this.meta.mycelium, this.runState);
+      this.hasDepositedThisRun = true;
+    }
+
+    // Stop UIScene
+    this.scene.stop('UIScene');
+
+    // Slow-motion effect
+    this.cameras.main.fadeOut(2000, 0, 0, 0);
+    this.cameras.main.once('camerafadeoutcomplete', () => {
+      this.scene.start('DeathScene', {
+        meta: this.meta,
+        runState: this.runState,
+      });
+    });
+  }
+
+  /** Try to launch a projectile from active quick slot toward mouse */
+  private tryLaunchProjectile(): void {
+    const itemId = this.quickSlots.getActive();
+    if (!itemId || !this.inventory.hasItem(itemId)) {
+      this.showInteractionFeedback('nothing_nearby');
+      return;
+    }
+
+    const removed = this.inventory.removeItem(itemId, 1);
+    if (removed === 0) return;
+
+    // Get mouse world position for direction
+    const pointer = this.input.activePointer;
+    const worldPoint = this.cameras.main.getWorldPoint(pointer.x, pointer.y);
+
+    const px = Position.x[this.playerEid];
+    const py = Position.y[this.playerEid];
+
+    launchProjectile(
+      this.gameWorld.world,
+      this.projectileData,
+      px, py,
+      worldPoint.x, worldPoint.y,
+      itemId,
+    );
+
+    // Check if this compound neutralizes the crisis
+    if (this.crisisState?.active && itemId === CHEMICAL_PLAGUE.neutralizer) {
+      attemptNeutralize(this.crisisState, itemId, 1);
+      if (this.crisisState.resolved) {
+        this.runState.crisisResolved = true;
+        this.runState.crisisActive = false;
+        this.crisisOverlay.setFillStyle(0x88ff88, 0);
+        this.showInteractionFeedback('collected', '✓ Чума нейтрализована!');
+        advancePhase(this.runState); // Crisis → Resolution
+      } else {
+        this.showInteractionFeedback('collected', `Нейтрализация: ${this.crisisState.neutralizeApplied}/${CHEMICAL_PLAGUE.neutralizeAmount}`);
+      }
+    }
+
+    // Clear quick slot if inventory is now empty for this item
+    if (!this.inventory.hasItem(itemId)) {
+      const slotIdx = this.quickSlots.getAll().indexOf(itemId);
+      if (slotIdx >= 0) this.quickSlots.assign(slotIdx, null);
+    }
+
+    if (!this.crisisState?.active || itemId !== CHEMICAL_PLAGUE.neutralizer) {
+      this.showInteractionFeedback('collected', `Threw ${itemId}`);
+    }
+  }
+
+  /** Transition to the boss arena (triggered when Resolution phase ends) */
+  private enterBossArena(): void {
+    if (this.playerDead) return;
+
+    // Prevent re-entry
+    this.playerDead = true; // Reuse flag to stop updates
+
+    // Auto-deposit discoveries before leaving
+    if (!this.hasDepositedThisRun) {
+      depositKnowledge(this.meta.mycelium, this.runState);
+      this.hasDepositedThisRun = true;
+    }
+
+    this.showInteractionFeedback('collected', '⚔ Вход в арену Уробороса...');
+
+    // Fade out and transition
+    this.time.delayedCall(1500, () => {
+      this.scene.stop('UIScene');
+      this.cameras.main.fadeOut(1000, 0, 0, 0);
+      this.cameras.main.once('camerafadeoutcomplete', () => {
+        this.scene.start('BossArenaScene', {
+          meta: this.meta,
+          runState: this.runState,
+          inventoryItems: this.inventory.getItems(),
+          quickSlotItems: this.quickSlots.getAll(),
+          activeSlot: this.quickSlots.activeIndex,
+          playerHealth: Health.current[this.playerEid] ?? 100,
+          playerMaxHealth: Health.max[this.playerEid] ?? 100,
+        });
+      });
+    });
+  }
+
+  private showInteractionFeedback(type: string, itemId?: string): void {
+    let msg = '';
+    switch (type) {
+      case 'collected':
+        msg = itemId?.startsWith('Threw') || itemId?.startsWith('⚠') || itemId?.startsWith('✓') || itemId?.startsWith('Нейтрализация')
+          ? itemId
+          : `+1 ${itemId ?? ''}`;
+        break;
+      case 'depleted':
+        msg = `+1 ${itemId ?? ''} (depleted)`;
+        break;
+      case 'inventory_full':
+        msg = `Inventory full! Can't pick up ${itemId ?? ''}`;
+        break;
+      case 'nothing_nearby':
+        msg = 'Nothing to throw / interact with';
+        break;
+    }
+    this.interactionText.setText(msg);
+    this.interactionText.setAlpha(1);
+    this.interactionTimer = 1500;
+  }
+}

src/scenes/RenewalScene.ts

@@ -0,0 +1,265 @@
+/**
+ * RenewalScene — Great Renewal (Великое Обновление)
+ *
+ * GDD spec:
+ * After every 7th run, the world experiences a Great Renewal:
+ * - World generation fundamentally changes
+ * - New lore layer unlocks
+ * - Mycelium "matures" — opens new capabilities
+ * - Previous 7 runs leave traces in the next cycle
+ *
+ * Visual: A special transition between great cycles with
+ * pulsing Mycelium, cycle counter, and narrative theme reveal.
+ */
+
+import Phaser from 'phaser';
+import type { MetaState, CycleTheme } from '../run/types';
+import { CYCLE_THEME_NAMES_RU } from '../run/types';
+import { GAME_WIDTH, GAME_HEIGHT } from '../config';
+import narrativeData from '../data/cycle-narrative.json';
+
+interface ThemeNarrative {
+  nameRu: string;
+  cradleQuoteRu: string;
+  loreFrag: { textRu: string }[];
+}
+
+export class RenewalScene extends Phaser.Scene {
+  private meta!: MetaState;
+  private previousCycle!: number;
+  private newCycle!: number;
+  private newTheme!: CycleTheme;
+  private elapsed = 0;
+  private readonly duration = 15000; // 15 seconds
+  private graphics!: Phaser.GameObjects.Graphics;
+  private particles: { x: number; y: number; vx: number; vy: number; r: number; alpha: number; color: number }[] = [];
+
+  constructor() {
+    super({ key: 'RenewalScene' });
+  }
+
+  init(data: { meta: MetaState; previousCycle: number }): void {
+    this.meta = data.meta;
+    this.previousCycle = data.previousCycle;
+    this.newCycle = this.meta.greatCycle.cycleNumber;
+    this.newTheme = this.meta.greatCycle.theme;
+    this.elapsed = 0;
+    this.particles = [];
+  }
+
+  create(): void {
+    this.cameras.main.setBackgroundColor('#010204');
+    this.graphics = this.add.graphics();
+
+    const cx = GAME_WIDTH / 2;
+    const cy = GAME_HEIGHT / 2;
+
+    // Create Mycelium pulse particles (more than fractal — representing the network)
+    for (let i = 0; i < 150; i++) {
+      const angle = Math.random() * Math.PI * 2;
+      const dist = Math.random() * 350;
+      this.particles.push({
+        x: cx + Math.cos(angle) * dist,
+        y: cy + Math.sin(angle) * dist,
+        vx: (Math.random() - 0.5) * 30,
+        vy: (Math.random() - 0.5) * 30,
+        r: 1 + Math.random() * 3,
+        alpha: Math.random() * 0.4,
+        color: Phaser.Display.Color.HSLToColor(
+          0.35 + Math.random() * 0.15, // green-teal hues
+          0.5 + Math.random() * 0.3,
+          0.2 + Math.random() * 0.3,
+        ).color,
+      });
+    }
+
+    // ─── Staged Text Reveals ─────────────────────────────────
+
+    // 1. "Великое Обновление" title (fades in at 0s)
+    const renewalMsg = this.pickRenewalMessage();
+    const titleText = this.add.text(cx, cy - 100, 'ВЕЛИКОЕ ОБНОВЛЕНИЕ', {
+      fontSize: '30px',
+      color: '#00ff88',
+      fontFamily: 'monospace',
+      fontStyle: 'bold',
+    }).setOrigin(0.5).setAlpha(0).setDepth(10);
+
+    this.tweens.add({
+      targets: titleText,
+      alpha: 1,
+      duration: 2000,
+    });
+
+    // 2. Renewal flavor message (fades in at 2s)
+    const flavorText = this.add.text(cx, cy - 55, renewalMsg, {
+      fontSize: '13px',
+      color: '#448866',
+      fontFamily: 'monospace',
+    }).setOrigin(0.5).setAlpha(0).setDepth(10);
+
+    this.tweens.add({
+      targets: flavorText,
+      alpha: 0.8,
+      duration: 1500,
+      delay: 2000,
+    });
+
+    // 3. Cycle counter "Цикл 1 → Цикл 2" (fades in at 4s)
+    const cycleText = this.add.text(cx, cy,
+      `Цикл ${this.previousCycle} → Цикл ${this.newCycle}`, {
+        fontSize: '22px',
+        color: '#ffffff',
+        fontFamily: 'monospace',
+        fontStyle: 'bold',
+      }).setOrigin(0.5).setAlpha(0).setDepth(10);
+
+    this.tweens.add({
+      targets: cycleText,
+      alpha: 1,
+      duration: 1500,
+      delay: 4000,
+    });
+
+    // 4. New theme name (fades in at 6s)
+    const themeName = CYCLE_THEME_NAMES_RU[this.newTheme];
+    const themeText = this.add.text(cx, cy + 40,
+      `Тема: ${themeName}`, {
+        fontSize: '18px',
+        color: '#44ddaa',
+        fontFamily: 'monospace',
+      }).setOrigin(0.5).setAlpha(0).setDepth(10);
+
+    this.tweens.add({
+      targets: themeText,
+      alpha: 1,
+      duration: 1500,
+      delay: 6000,
+    });
+
+    // 5. Lore fragment from the new theme (fades in at 8s)
+    const narrative = this.getThemeNarrative(this.newTheme);
+    if (narrative && narrative.loreFrag.length > 0) {
+      const fragIdx = this.newCycle % narrative.loreFrag.length;
+      const loreText = this.add.text(cx, cy + 90,
+        `«${narrative.loreFrag[fragIdx].textRu}»`, {
+          fontSize: '12px',
+          color: '#668866',
+          fontFamily: 'monospace',
+          fontStyle: 'italic',
+          align: 'center',
+          wordWrap: { width: GAME_WIDTH * 0.7 },
+        }).setOrigin(0.5).setAlpha(0).setDepth(10);
+
+      this.tweens.add({
+        targets: loreText,
+        alpha: 0.7,
+        duration: 2000,
+        delay: 8000,
+      });
+    }
+
+    // 6. Mycelium maturation info (fades in at 10s)
+    const matPct = Math.round(this.meta.greatCycle.myceliumMaturation * 100);
+    const matText = this.add.text(cx, cy + 140,
+      `Мицелий созревает... (${matPct}%)`, {
+        fontSize: '12px',
+        color: '#33aa66',
+        fontFamily: 'monospace',
+      }).setOrigin(0.5).setAlpha(0).setDepth(10);
+
+    this.tweens.add({
+      targets: matText,
+      alpha: 0.6,
+      duration: 1500,
+      delay: 10000,
+    });
+
+    // Skip hint
+    const skipText = this.add.text(cx, GAME_HEIGHT - 25,
+      '[ click to skip ]', {
+        fontSize: '10px',
+        color: '#333333',
+        fontFamily: 'monospace',
+      }).setOrigin(0.5).setDepth(100);
+
+    // Click to skip after minimum 5 seconds
+    this.input.on('pointerdown', () => {
+      if (this.elapsed > 5000) {
+        this.transitionToCradle();
+      }
+    });
+  }
+
+  update(_time: number, delta: number): void {
+    this.elapsed += delta;
+
+    // Animate Mycelium particles
+    this.graphics.clear();
+    const cx = GAME_WIDTH / 2;
+    const cy = GAME_HEIGHT / 2;
+    const t = this.elapsed / 1000;
+
+    for (const p of this.particles) {
+      // Spiral inward then outward (breathing effect)
+      const dx = cx - p.x;
+      const dy = cy - p.y;
+      const dist = Math.sqrt(dx * dx + dy * dy) || 1;
+      const breathe = Math.sin(t * 0.5) * 0.3;
+
+      p.vx += (dx / dist) * breathe;
+      p.vy += (dy / dist) * breathe;
+
+      p.x += p.vx * (delta / 1000);
+      p.y += p.vy * (delta / 1000);
+
+      // Damping
+      p.vx *= 0.98;
+      p.vy *= 0.98;
+
+      // Pulsing alpha
+      p.alpha = 0.1 + Math.sin(t * 1.5 + dist * 0.01) * 0.2;
+
+      this.graphics.fillStyle(p.color, Math.max(0.02, p.alpha));
+      this.graphics.fillCircle(p.x, p.y, p.r);
+
+      // Mycelium threads — connecting nearby particles
+      if (Math.random() < 0.01) {
+        const other = this.particles[Math.floor(Math.random() * this.particles.length)];
+        const threadDist = Math.hypot(p.x - other.x, p.y - other.y);
+        if (threadDist < 80) {
+          this.graphics.lineStyle(1, 0x33aa66, 0.08);
+          this.graphics.beginPath();
+          this.graphics.moveTo(p.x, p.y);
+          this.graphics.lineTo(other.x, other.y);
+          this.graphics.strokePath();
+        }
+      }
+    }
+
+    // Auto-transition after duration
+    if (this.elapsed >= this.duration) {
+      this.transitionToCradle();
+    }
+  }
+
+  private pickRenewalMessage(): string {
+    const messages = narrativeData.renewalMessages;
+    const idx = this.previousCycle % messages.length;
+    return messages[idx].textRu;
+  }
+
+  private getThemeNarrative(theme: CycleTheme): ThemeNarrative | null {
+    const themes = narrativeData.themes as Record<string, ThemeNarrative>;
+    return themes[theme] ?? null;
+  }
+
+  private transitionToCradle(): void {
+    if ((this as unknown as { _transitioning?: boolean })._transitioning) return;
+    (this as unknown as { _transitioning?: boolean })._transitioning = true;
+
+    this.cameras.main.fadeOut(2000, 0, 0, 0);
+    this.cameras.main.once('camerafadeoutcomplete', () => {
+      this.scene.start('CradleScene', { meta: this.meta });
+    });
+  }
+}

src/scenes/UIScene.ts

@@ -0,0 +1,226 @@
+/**
+ * UIScene — HUD overlay on top of GameScene
+ *
+ * Renders health bar, quick slots, inventory weight.
+ * Reads shared game state from Phaser registry.
+ */
+
+import Phaser from 'phaser';
+import { SLOT_COUNT } from '../player/quickslots';
+import { ElementRegistry } from '../chemistry/elements';
+import { CompoundRegistry } from '../chemistry/compounds';
+
+const SLOT_SIZE = 44;
+const SLOT_GAP = 4;
+const HEALTH_BAR_WIDTH = 160;
+const HEALTH_BAR_HEIGHT = 14;
+
+/** Get color for a chemical item as number (for rendering) */
+function getItemDisplayColor(itemId: string): number {
+  const el = ElementRegistry.getBySymbol(itemId);
+  if (el) return parseInt(el.color.replace('#', ''), 16);
+  const comp = CompoundRegistry.getById(itemId);
+  if (comp) return parseInt(comp.color.replace('#', ''), 16);
+  return 0xffffff;
+}
+
+/** Get display name for a chemical item */
+function getItemDisplayName(itemId: string): string {
+  const el = ElementRegistry.getBySymbol(itemId);
+  if (el) return el.symbol;
+  const comp = CompoundRegistry.getById(itemId);
+  if (comp) return comp.formula;
+  return itemId;
+}
+
+export class UIScene extends Phaser.Scene {
+  // Health
+  private healthBarBg!: Phaser.GameObjects.Rectangle;
+  private healthBarFill!: Phaser.GameObjects.Rectangle;
+  private healthText!: Phaser.GameObjects.Text;
+
+  // Quick slots
+  private slotBoxes: Phaser.GameObjects.Rectangle[] = [];
+  private slotTexts: Phaser.GameObjects.Text[] = [];
+  private slotNumTexts: Phaser.GameObjects.Text[] = [];
+  private slotCountTexts: Phaser.GameObjects.Text[] = [];
+
+  // Inventory
+  private invText!: Phaser.GameObjects.Text;
+
+  // Controls hint
+  private controlsText!: Phaser.GameObjects.Text;
+
+  // Cycle info (top-left, below health)
+  private cycleText!: Phaser.GameObjects.Text;
+
+  // Run phase (top-left, below cycle)
+  private phaseText!: Phaser.GameObjects.Text;
+
+  constructor() {
+    super({ key: 'UIScene' });
+  }
+
+  create(): void {
+    const w = this.cameras.main.width;
+    const h = this.cameras.main.height;
+
+    // === Health bar (top-left) ===
+    const hpX = 12;
+    const hpY = 12;
+
+    this.healthBarBg = this.add.rectangle(
+      hpX + HEALTH_BAR_WIDTH / 2, hpY + HEALTH_BAR_HEIGHT / 2,
+      HEALTH_BAR_WIDTH, HEALTH_BAR_HEIGHT, 0x330000,
+    );
+    this.healthBarBg.setStrokeStyle(1, 0x660000);
+
+    this.healthBarFill = this.add.rectangle(
+      hpX + HEALTH_BAR_WIDTH / 2, hpY + HEALTH_BAR_HEIGHT / 2,
+      HEALTH_BAR_WIDTH, HEALTH_BAR_HEIGHT, 0x00cc44,
+    );
+
+    this.healthText = this.add.text(
+      hpX + HEALTH_BAR_WIDTH + 8, hpY, '', {
+        fontSize: '12px',
+        color: '#00ff88',
+        fontFamily: 'monospace',
+      },
+    );
+
+    // === Quick slots (bottom-center) ===
+    const totalW = SLOT_COUNT * SLOT_SIZE + (SLOT_COUNT - 1) * SLOT_GAP;
+    const startX = (w - totalW) / 2;
+    const startY = h - SLOT_SIZE - 12;
+
+    for (let i = 0; i < SLOT_COUNT; i++) {
+      const x = startX + i * (SLOT_SIZE + SLOT_GAP);
+      const cx = x + SLOT_SIZE / 2;
+      const cy = startY + SLOT_SIZE / 2;
+
+      // Slot background
+      const box = this.add.rectangle(cx, cy, SLOT_SIZE, SLOT_SIZE, 0x111111, 0.85);
+      box.setStrokeStyle(2, 0x444444);
+      this.slotBoxes.push(box);
+
+      // Slot number (top-left corner)
+      const numText = this.add.text(x + 3, startY + 2, `${i + 1}`, {
+        fontSize: '10px',
+        color: '#555555',
+        fontFamily: 'monospace',
+      });
+      this.slotNumTexts.push(numText);
+
+      // Item name (center)
+      const itemText = this.add.text(cx, cy - 2, '', {
+        fontSize: '14px',
+        color: '#ffffff',
+        fontFamily: 'monospace',
+        fontStyle: 'bold',
+      });
+      itemText.setOrigin(0.5);
+      this.slotTexts.push(itemText);
+
+      // Count (bottom-right)
+      const countText = this.add.text(x + SLOT_SIZE - 3, startY + SLOT_SIZE - 3, '', {
+        fontSize: '10px',
+        color: '#aaaaaa',
+        fontFamily: 'monospace',
+      });
+      countText.setOrigin(1, 1);
+      this.slotCountTexts.push(countText);
+    }
+
+    // === Inventory info (bottom-right) ===
+    this.invText = this.add.text(w - 12, h - 14, '', {
+      fontSize: '11px',
+      color: '#888888',
+      fontFamily: 'monospace',
+      backgroundColor: '#000000aa',
+      padding: { x: 4, y: 2 },
+    });
+    this.invText.setOrigin(1, 1);
+
+    // === Cycle info (top-left, below health bar) ===
+    this.cycleText = this.add.text(12, 32, '', {
+      fontSize: '10px',
+      color: '#446644',
+      fontFamily: 'monospace',
+    });
+
+    // === Run phase (below cycle) ===
+    this.phaseText = this.add.text(12, 46, '', {
+      fontSize: '10px',
+      color: '#557755',
+      fontFamily: 'monospace',
+    });
+
+    // === Controls hint (top-right) ===
+    this.controlsText = this.add.text(w - 12, 12, 'WASD move | E collect | F throw | 1-4 slots | scroll zoom', {
+      fontSize: '10px',
+      color: '#444444',
+      fontFamily: 'monospace',
+    });
+    this.controlsText.setOrigin(1, 0);
+  }
+
+  update(): void {
+    // === Read shared state from registry ===
+    const health = (this.registry.get('health') as number) ?? 100;
+    const healthMax = (this.registry.get('healthMax') as number) ?? 100;
+    const slots = (this.registry.get('quickSlots') as (string | null)[]) ?? [];
+    const activeSlot = (this.registry.get('activeSlot') as number) ?? 0;
+    const invWeight = (this.registry.get('invWeight') as number) ?? 0;
+    const invMaxWeight = (this.registry.get('invMaxWeight') as number) ?? 500;
+    const invSlots = (this.registry.get('invSlots') as number) ?? 0;
+    const invCounts = (this.registry.get('invCounts') as Map<string, number>) ?? new Map();
+
+    // === Update health bar ===
+    const ratio = healthMax > 0 ? health / healthMax : 0;
+    const fillWidth = HEALTH_BAR_WIDTH * ratio;
+    this.healthBarFill.width = fillWidth;
+    this.healthBarFill.x = this.healthBarBg.x - (HEALTH_BAR_WIDTH - fillWidth) / 2;
+
+    // Color: green → yellow → red
+    const hpColor = ratio > 0.5 ? 0x00cc44 : ratio > 0.25 ? 0xccaa00 : 0xcc2200;
+    this.healthBarFill.setFillStyle(hpColor);
+    this.healthText.setText(`${Math.round(health)}/${healthMax}`);
+
+    // === Update quick slots ===
+    for (let i = 0; i < SLOT_COUNT; i++) {
+      const itemId = i < slots.length ? slots[i] : null;
+      const isActive = i === activeSlot;
+
+      // Border color
+      this.slotBoxes[i].setStrokeStyle(2, isActive ? 0x00ff88 : 0x444444);
+      this.slotBoxes[i].setFillStyle(isActive ? 0x1a2a1a : 0x111111, 0.85);
+
+      if (itemId) {
+        const displayName = getItemDisplayName(itemId);
+        const displayColor = getItemDisplayColor(itemId);
+        this.slotTexts[i].setText(displayName);
+        this.slotTexts[i].setColor(`#${displayColor.toString(16).padStart(6, '0')}`);
+
+        const count = invCounts.get(itemId) ?? 0;
+        this.slotCountTexts[i].setText(count > 0 ? `${count}` : '0');
+        this.slotCountTexts[i].setColor(count > 0 ? '#aaaaaa' : '#660000');
+      } else {
+        this.slotTexts[i].setText('');
+        this.slotCountTexts[i].setText('');
+      }
+    }
+
+    // === Update inventory ===
+    this.invText.setText(`${Math.round(invWeight)}/${invMaxWeight} AMU | ${invSlots} items`);
+
+    // === Update cycle info ===
+    const cycleNumber = (this.registry.get('cycleNumber') as number) ?? 1;
+    const runInCycle = (this.registry.get('runInCycle') as number) ?? 1;
+    const cycleTheme = (this.registry.get('cycleThemeRu') as string) ?? '';
+    this.cycleText.setText(`Цикл ${cycleNumber}: ${cycleTheme} | Ран ${runInCycle}/7`);
+
+    // === Update run phase ===
+    const runPhaseRu = (this.registry.get('runPhaseRu') as string) ?? '';
+    this.phaseText.setText(runPhaseRu);
+  }
+}

src/ui/screen-fix.ts

@@ -0,0 +1,31 @@
+import type Phaser from 'phaser';
+
+/**
+ * Position a scrollFactor(0) game object at fixed screen coordinates,
+ * compensating for camera zoom.
+ *
+ * Phaser's camera zoom scales around the viewport center, which displaces
+ * scrollFactor(0) objects:
+ *   screenPos = (objPos − center) × zoom + center
+ *
+ * This function solves for the object position that maps to the desired
+ * screen pixel, and counter-scales the object so it appears at 1× size:
+ *   objPos = (desiredScreen − center) / zoom + center
+ *   scale  = baseScale / zoom
+ *
+ * Call every frame for each UI element that uses setScrollFactor(0).
+ */
+export function fixToScreen(
+  obj: { x: number; y: number; setScale(x: number, y?: number): unknown },
+  screenX: number,
+  screenY: number,
+  camera: Phaser.Cameras.Scene2D.Camera,
+  baseScale = 1,
+): void {
+  const zoom = camera.zoom;
+  const cx = camera.width * 0.5;
+  const cy = camera.height * 0.5;
+  obj.x = (screenX - cx) / zoom + cx;
+  obj.y = (screenY - cy) / zoom + cy;
+  obj.setScale(baseScale / zoom);
+}

src/world/camera.ts

@@ -67,3 +67,29 @@ export function updateCamera(
   if (keys.up.isDown) camera.scrollY -= speed * dt;
   if (keys.down.isDown) camera.scrollY += speed * dt;
 }
+
+/**
+ * Set up camera for player-follow mode.
+ * No WASD movement — camera follows the player entity.
+ * Zoom via mouse wheel, bounds clamped to world size.
+ */
+export function setupPlayerCamera(
+  scene: Phaser.Scene,
+  worldPixelWidth: number,
+  worldPixelHeight: number,
+): void {
+  const camera = scene.cameras.main;
+  camera.setBounds(0, 0, worldPixelWidth, worldPixelHeight);
+  camera.setZoom(2); // closer view for gameplay
+
+  // Mouse wheel zoom (0.5x – 3x)
+  scene.input.on('wheel', (
+    _pointer: unknown,
+    _gameObjects: unknown,
+    _deltaX: number,
+    deltaY: number,
+  ) => {
+    const newZoom = Phaser.Math.Clamp(camera.zoom - deltaY * 0.001, 0.5, 3);
+    camera.setZoom(newZoom);
+  });
+}

src/world/generator.ts

@@ -47,21 +47,27 @@ function determineTile(elevation: number, detail: number, biome: BiomeData): num
     }
   }
 
-  // Geyser overlay: on acid-shallow + very high detail noise
+  // Interactive overlay (geysers / steam vents / hollow stumps) on specific base tile + high detail noise
   if (baseTileId === gen.geyserOnTile && detail > gen.geyserThreshold) {
-    return findTileIdByName(biome, 'geyser');
+    return findInteractiveTileId(biome);
   }
 
-  // Mineral overlay: on walkable ground + high detail noise
+  // Resource overlay (mineral veins / ore deposits / herb patches) on walkable ground + high detail noise
   if (gen.mineralOnTiles.includes(baseTileId) && detail > gen.mineralThreshold) {
-    return findTileIdByName(biome, 'mineral-vein');
+    return findResourceTileId(biome);
   }
 
   return baseTileId;
 }
 
-/** Find tile ID by name, falling back to 0 if not found */
+/** Find the interactive tile (geyser/steam-vent/hollow-stump), falling back to 0 */
-function findTileIdByName(biome: BiomeData, name: string): number {
+function findInteractiveTileId(biome: BiomeData): number {
-  const tile = biome.tiles.find(t => t.name === name);
+  const tile = biome.tiles.find(t => t.interactive);
+  return tile ? tile.id : 0;
+}
+
+/** Find the resource tile (mineral-vein/ore-deposit/herb-patch), falling back to 0 */
+function findResourceTileId(biome: BiomeData): number {
+  const tile = biome.tiles.find(t => t.resource);
   return tile ? tile.id : 0;
 }

src/world/minimap.ts

@@ -1,5 +1,6 @@
 import Phaser from 'phaser';
 import type { TileData, TileGrid, WorldData } from './types';
+import { fixToScreen } from '../ui/screen-fix';
 
 const MINIMAP_DEPTH = 100;
 const VIEWPORT_DEPTH = 101;
@@ -82,6 +83,10 @@ export class Minimap {
     const canvasW = w * scale;
     const canvasH = h * scale;
 
+    // Remove old texture if re-entering scene (run cycle)
+    if (scene.textures.exists('minimap')) {
+      scene.textures.remove('minimap');
+    }
     const canvasTexture = scene.textures.createCanvas('minimap', canvasW, canvasH);
     const ctx = canvasTexture.getContext();
 
@@ -98,8 +103,17 @@ export class Minimap {
 
   /** Update the viewport indicator rectangle — call each frame */
   update(camera: Phaser.Cameras.Scene2D.Camera): void {
+    // Compensate for camera zoom on all minimap elements.
+    // Graphics objects (border, viewport) use (0,0) as origin so their
+    // local draw coordinates map 1:1 to screen pixels after compensation.
+    fixToScreen(this.border, 0, 0, camera);
+    fixToScreen(this.viewport, 0, 0, camera);
+
+    // Image has origin(1,0): position = top-right corner
     const screenW = camera.width;
     const padding = 10;
+    fixToScreen(this.image, screenW - padding, padding, camera);
+
     const minimapW = this.mapWidth * this.minimapScale;
     const minimapX = screenW - padding - minimapW;
     const minimapY = padding;

src/world/resources.ts

@@ -0,0 +1,106 @@
+/**
+ * Resource Spawner — creates ECS entities for harvestable world objects
+ *
+ * Scans the generated tile grid for mineral veins and geysers,
+ * creates an entity at each with a randomly assigned element.
+ */
+
+import { addEntity, addComponent } from 'bitecs';
+import type { World } from '../ecs/world';
+import { Position, Resource, SpriteRef } from '../ecs/components';
+import type { TileGrid, BiomeData } from './types';
+import {
+  pickResourceElement,
+  MINERAL_ELEMENTS,
+  GEYSER_ELEMENTS,
+  type ResourceInfo,
+} from '../player/interaction';
+
+/** Resource spawn configuration per tile type */
+interface ResourceTileConfig {
+  tileId: number;
+  elements: readonly string[];
+  minQuantity: number;
+  maxQuantity: number;
+  interactRange: number;
+  spriteColor: number;
+  spriteRadius: number;
+}
+
+/**
+ * Spawn resource entities for all resource tiles in the grid.
+ * @returns Map of entity ID → ResourceInfo for string data
+ */
+export function spawnResources(
+  world: World,
+  grid: TileGrid,
+  biome: BiomeData,
+  seed: number,
+): Map<number, ResourceInfo> {
+  const resourceData = new Map<number, ResourceInfo>();
+
+  // Find tile IDs for resource types (generic: resource + interactive tiles)
+  const mineralTile = biome.tiles.find(t => t.resource);
+  const geyserTile = biome.tiles.find(t => t.interactive);
+
+  const configs: ResourceTileConfig[] = [];
+
+  if (mineralTile) {
+    configs.push({
+      tileId: mineralTile.id,
+      elements: MINERAL_ELEMENTS,
+      minQuantity: 3,
+      maxQuantity: 5,
+      interactRange: 40,
+      spriteColor: 0xffd700, // gold
+      spriteRadius: 4,
+    });
+  }
+
+  if (geyserTile) {
+    configs.push({
+      tileId: geyserTile.id,
+      elements: GEYSER_ELEMENTS,
+      minQuantity: 2,
+      maxQuantity: 4,
+      interactRange: 48,
+      spriteColor: 0xff6600, // orange
+      spriteRadius: 5,
+    });
+  }
+
+  const tileSize = biome.tileSize;
+
+  for (let y = 0; y < grid.length; y++) {
+    for (let x = 0; x < grid[y].length; x++) {
+      const tileId = grid[y][x];
+      const config = configs.find(c => c.tileId === tileId);
+      if (!config) continue;
+
+      // Pick element deterministically
+      const itemId = pickResourceElement(x, y, seed, config.elements);
+
+      // Quantity from deterministic hash
+      const qHash = ((x * 48611) ^ (y * 29423) ^ (seed * 61379)) >>> 0;
+      const range = config.maxQuantity - config.minQuantity + 1;
+      const quantity = config.minQuantity + (qHash % range);
+
+      // Create entity at tile center
+      const eid = addEntity(world);
+      addComponent(world, eid, Position);
+      addComponent(world, eid, Resource);
+      addComponent(world, eid, SpriteRef);
+
+      Position.x[eid] = x * tileSize + tileSize / 2;
+      Position.y[eid] = y * tileSize + tileSize / 2;
+      Resource.quantity[eid] = quantity;
+      Resource.interactRange[eid] = config.interactRange;
+      SpriteRef.color[eid] = config.spriteColor;
+      SpriteRef.radius[eid] = config.spriteRadius;
+
+      resourceData.set(eid, { itemId, tileX: x, tileY: y });
+    }
+  }
+
+  return resourceData;
+}

src/world/tilemap.ts

@@ -15,7 +15,12 @@ export function createWorldTilemap(
   const { grid, biome } = worldData;
   const textureKey = `tileset-${biome.id}`;
 
-  // 1. Generate tileset texture
+  // 1. Remove old texture if re-entering scene (run cycle)
+  if (scene.textures.exists(textureKey)) {
+    scene.textures.remove(textureKey);
+  }
+
+  // 2. Generate tileset texture
   createTilesetTexture(scene, biome.tiles, biome.tileSize, textureKey);
 
   // 2. Create tilemap from grid

src/world/traces.ts

@@ -0,0 +1,194 @@
+/**
+ * World Trace Placement — places ruins and markers from past runs
+ *
+ * GDD (Law of Trace): "Nothing disappears without a trace;
+ * each cycle leaves an imprint in the next."
+ *
+ * When generating a new world, we check for traces from past runs
+ * in the same biome (from the current and previous great cycle).
+ * Death sites become ruin markers; discovery sites become faded experiment traces.
+ */
+
+import { addEntity, addComponent } from 'bitecs';
+import type { World } from '../ecs/world';
+import { Position, SpriteRef, WorldTrace, TraceType } from '../ecs/components';
+import type { BiomeData } from './types';
+import type { RunTrace, GreatCycleState } from '../run/types';
+import { getTracesForBiome, getDeathTraces } from '../run/cycle';
+
+/** String data for a world trace entity (not stored in ECS — numeric only there) */
+export interface WorldTraceInfo {
+  /** Entity ID */
+  eid: number;
+  /** Type of trace */
+  traceType: 'death_site' | 'discovery_site';
+  /** Run that left this trace */
+  sourceRunId: number;
+  /** School used in that run */
+  schoolId: string;
+  /** Key elements discovered (for discovery sites) */
+  keyElements: string[];
+  /** Tile position */
+  tileX: number;
+  tileY: number;
+}
+
+/** Visual config for trace markers */
+const TRACE_CONFIG = {
+  death_site: {
+    color: 0x884444,     // dark red — blood/decay
+    radius: 6,
+    interactRange: 40,
+    glowColor: 0xaa3333, // red glow
+  },
+  discovery_site: {
+    color: 0x446688,     // blue-gray — knowledge
+    radius: 5,
+    interactRange: 36,
+    glowColor: 0x4488aa, // blue glow
+  },
+} as const;
+
+/**
+ * Spawn world trace entities from past run traces.
+ *
+ * For each trace from the current/previous cycle in this biome:
+ * - Death sites: place a ruin marker at the death position
+ * - Remaining traces: place discovery markers at a position derived from
+ *   the run's world seed (since we don't store exact discovery locations)
+ *
+ * @returns Array of WorldTraceInfo for display/interaction
+ */
+export function spawnWorldTraces(
+  world: World,
+  cycleState: GreatCycleState,
+  biomeId: string,
+  biome: BiomeData,
+): WorldTraceInfo[] {
+  const traces = getTracesForBiome(cycleState, biomeId);
+  if (traces.length === 0) return [];
+
+  const result: WorldTraceInfo[] = [];
+  const tileSize = biome.tileSize;
+  const mapW = biome.mapWidth;
+  const mapH = biome.mapHeight;
+
+  // Place death site markers
+  const deathTraces = getDeathTraces(traces);
+  for (const trace of deathTraces) {
+    const pos = trace.deathPosition;
+    if (!pos) continue;
+
+    // Clamp to map bounds
+    const tx = Math.max(0, Math.min(pos.tileX, mapW - 1));
+    const ty = Math.max(0, Math.min(pos.tileY, mapH - 1));
+
+    const eid = createTraceEntity(
+      world, tx, ty, tileSize,
+      TraceType.DeathSite, trace.runId,
+      TRACE_CONFIG.death_site,
+    );
+
+    result.push({
+      eid,
+      traceType: 'death_site',
+      sourceRunId: trace.runId,
+      schoolId: trace.schoolId,
+      keyElements: trace.keyElements,
+      tileX: tx,
+      tileY: ty,
+    });
+  }
+
+  // Place discovery markers for traces with significant discoveries
+  // (Only for traces without death sites, to avoid double-marking)
+  const deathRunIds = new Set(deathTraces.map(t => t.runId));
+  const discoveryTraces = traces.filter(
+    t => !deathRunIds.has(t.runId) && t.discoveryCount >= 3,
+  );
+
+  for (const trace of discoveryTraces) {
+    // Derive a position from the run's seed (deterministic but varied)
+    const tx = deriveTracePosition(trace.worldSeed, 0, mapW);
+    const ty = deriveTracePosition(trace.worldSeed, 1, mapH);
+
+    const eid = createTraceEntity(
+      world, tx, ty, tileSize,
+      TraceType.DiscoverySite, trace.runId,
+      TRACE_CONFIG.discovery_site,
+    );
+
+    result.push({
+      eid,
+      traceType: 'discovery_site',
+      sourceRunId: trace.runId,
+      schoolId: trace.schoolId,
+      keyElements: trace.keyElements,
+      tileX: tx,
+      tileY: ty,
+    });
+  }
+
+  return result;
+}
+
+/** Create a single trace entity with position, sprite, and trace component */
+function createTraceEntity(
+  world: World,
+  tileX: number,
+  tileY: number,
+  tileSize: number,
+  traceType: number,
+  sourceRunId: number,
+  config: { color: number; radius: number; interactRange: number },
+): number {
+  const eid = addEntity(world);
+
+  addComponent(world, eid, Position);
+  Position.x[eid] = tileX * tileSize + tileSize / 2;
+  Position.y[eid] = tileY * tileSize + tileSize / 2;
+
+  addComponent(world, eid, SpriteRef);
+  SpriteRef.color[eid] = config.color;
+  SpriteRef.radius[eid] = config.radius;
+
+  addComponent(world, eid, WorldTrace);
+  WorldTrace.traceType[eid] = traceType;
+  WorldTrace.sourceRunId[eid] = sourceRunId;
+  WorldTrace.glowPhase[eid] = Math.random() * Math.PI * 2;
+  WorldTrace.interactRange[eid] = config.interactRange;
+
+  return eid;
+}
+
+/**
+ * Derive a deterministic tile position from a seed.
+ * Ensures traces from the same run appear in consistent locations.
+ */
+function deriveTracePosition(seed: number, axis: number, mapSize: number): number {
+  // Mulberry32-style hash
+  let t = (seed + axis * 0x6d2b79f5 + 0x9e3779b9) | 0;
+  t = Math.imul(t ^ (t >>> 15), t | 1);
+  t ^= t + Math.imul(t ^ (t >>> 7), t | 61);
+  const normalized = ((t ^ (t >>> 14)) >>> 0) / 4294967296;
+
+  // Keep away from edges (10% margin)
+  const margin = Math.floor(mapSize * 0.1);
+  return margin + Math.floor(normalized * (mapSize - 2 * margin));
+}
+
+/**
+ * Update trace glow animation (pulsing effect).
+ * Called in the game update loop.
+ */
+export function updateTraceGlow(
+  traceInfos: WorldTraceInfo[],
+  delta: number,
+): void {
+  const pulseSpeed = 1.2; // radians per second
+  const deltaSec = delta / 1000;
+
+  for (const info of traceInfos) {
+    WorldTrace.glowPhase[info.eid] += pulseSpeed * deltaSec;
+  }
+}

tests/boss.test.ts

@@ -0,0 +1,758 @@
+/**
+ * Boss System Tests — Phase 8: First Archont (Ouroboros)
+ *
+ * Tests cover:
+ * - Boss state creation and initialization
+ * - Phase cycling (Coil → Spray → Lash → Digest → repeat)
+ * - Phase speedup per cycle
+ * - Damage mechanics (vulnerability windows, armor)
+ * - Chemical damage (NaOH during Spray)
+ * - Catalyst poison (Hg stacks, regen/armor reduction)
+ * - Victory detection and method determination
+ * - Arena generation (circular layout, features)
+ * - Reward calculation (spores, lore)
+ * - Boss entity factory (ECS)
+ */
+
+import { describe, it, expect, beforeEach } from 'vitest';
+import { createWorld, addEntity, addComponent, query } from 'bitecs';
+import type { World } from '../src/ecs/world';
+import { Position, Health, SpriteRef, Boss } from '../src/ecs/components';
+
+// Boss system imports
+import {
+  createBossState,
+  updateBossPhase,
+  getEffectiveArmor,
+  getEffectiveRegen,
+  isVulnerable,
+  getEffectivePhaseDuration,
+} from '../src/boss/ai';
+import {
+  applyBossDamage,
+  isBossDefeated,
+} from '../src/boss/victory';
+import {
+  generateArena,
+  buildArenaWalkableSet,
+} from '../src/boss/arena';
+import {
+  calculateBossReward,
+  applyBossReward,
+} from '../src/boss/reward';
+import { createBossEntity } from '../src/boss/factory';
+
+// Types
+import {
+  BossPhase,
+  VictoryMethod,
+  type BossData,
+  type BossState,
+} from '../src/boss/types';
+import type { BiomeData } from '../src/world/types';
+import { createMetaState } from '../src/run/meta';
+
+// Load boss data
+import bossDataArray from '../src/data/bosses.json';
+import biomeDataArray from '../src/data/biomes.json';
+
+const ouroboros = bossDataArray[0] as BossData;
+const biome = biomeDataArray[0] as BiomeData;
+
+// ─── Boss State Creation ─────────────────────────────────────────
+
+describe('Boss State Creation', () => {
+  it('creates initial boss state from data', () => {
+    const state = createBossState(ouroboros);
+    expect(state.bossId).toBe('ouroboros');
+    expect(state.health).toBe(300);
+    expect(state.maxHealth).toBe(300);
+    expect(state.currentPhase).toBe(BossPhase.Coil);
+    expect(state.cycleCount).toBe(0);
+    expect(state.catalystStacks).toBe(0);
+    expect(state.defeated).toBe(false);
+    expect(state.victoryMethod).toBeNull();
+  });
+
+  it('starts with phase timer set to first phase duration', () => {
+    const state = createBossState(ouroboros);
+    expect(state.phaseTimer).toBe(ouroboros.phaseDurations[0]); // 5000ms
+  });
+
+  it('starts with zero damage counters', () => {
+    const state = createBossState(ouroboros);
+    expect(state.totalDamageDealt).toBe(0);
+    expect(state.chemicalDamageDealt).toBe(0);
+    expect(state.directDamageDealt).toBe(0);
+    expect(state.catalystDamageDealt).toBe(0);
+  });
+});
+
+// ─── Phase Cycling ───────────────────────────────────────────────
+
+describe('Boss Phase Cycling', () => {
+  let state: BossState;
+
+  beforeEach(() => {
+    state = createBossState(ouroboros);
+  });
+
+  it('stays in current phase while timer has not expired', () => {
+    updateBossPhase(state, ouroboros, 1000);
+    expect(state.currentPhase).toBe(BossPhase.Coil);
+    expect(state.phaseTimer).toBeGreaterThan(0);
+  });
+
+  it('transitions from Coil to Spray when timer expires', () => {
+    updateBossPhase(state, ouroboros, 5000); // Full Coil duration
+    expect(state.currentPhase).toBe(BossPhase.Spray);
+  });
+
+  it('transitions through full cycle: Coil → Spray → Lash → Digest', () => {
+    // Coil (5s) → Spray
+    updateBossPhase(state, ouroboros, 5000);
+    expect(state.currentPhase).toBe(BossPhase.Spray);
+
+    // Spray (8s) → Lash
+    updateBossPhase(state, ouroboros, 8000);
+    expect(state.currentPhase).toBe(BossPhase.Lash);
+
+    // Lash (6s) → Digest
+    updateBossPhase(state, ouroboros, 6000);
+    expect(state.currentPhase).toBe(BossPhase.Digest);
+  });
+
+  it('completes a full cycle and increments cycleCount', () => {
+    // Full cycle: 5000 + 8000 + 6000 + 4000 = 23000ms
+    const events = [];
+    events.push(...updateBossPhase(state, ouroboros, 5000));  // Coil → Spray
+    events.push(...updateBossPhase(state, ouroboros, 8000));  // Spray → Lash
+    events.push(...updateBossPhase(state, ouroboros, 6000));  // Lash → Digest
+    events.push(...updateBossPhase(state, ouroboros, 4000));  // Digest → Coil (cycle 1)
+
+    expect(state.currentPhase).toBe(BossPhase.Coil);
+    expect(state.cycleCount).toBe(1);
+
+    const cycleEvent = events.find(e => e.type === 'cycle_complete');
+    expect(cycleEvent).toBeDefined();
+    expect(cycleEvent?.cycleCount).toBe(1);
+  });
+
+  it('emits phase_change events', () => {
+    const events = updateBossPhase(state, ouroboros, 5000); // Coil → Spray
+    const phaseChange = events.find(e => e.type === 'phase_change');
+    expect(phaseChange).toBeDefined();
+    expect(phaseChange?.phase).toBe(BossPhase.Spray);
+  });
+
+  it('emits boss_attack during Spray phase', () => {
+    updateBossPhase(state, ouroboros, 5000); // → Spray
+    const events = updateBossPhase(state, ouroboros, 100); // Tick in Spray
+    const attack = events.find(e => e.type === 'boss_attack');
+    expect(attack).toBeDefined();
+    expect(attack?.phase).toBe(BossPhase.Spray);
+  });
+
+  it('emits boss_attack during Lash phase', () => {
+    updateBossPhase(state, ouroboros, 5000 + 8000); // → Lash
+    const events = updateBossPhase(state, ouroboros, 100); // Tick in Lash
+    const attack = events.find(e => e.type === 'boss_attack');
+    expect(attack).toBeDefined();
+    expect(attack?.phase).toBe(BossPhase.Lash);
+  });
+
+  it('does not emit boss_attack during Coil or Digest', () => {
+    // During Coil
+    const coilEvents = updateBossPhase(state, ouroboros, 100);
+    expect(coilEvents.filter(e => e.type === 'boss_attack')).toHaveLength(0);
+
+    // Advance to Digest
+    updateBossPhase(state, ouroboros, 4900 + 8000 + 6000); // Coil → Spray → Lash → Digest
+    const digestEvents = updateBossPhase(state, ouroboros, 100);
+    expect(digestEvents.filter(e => e.type === 'boss_attack')).toHaveLength(0);
+  });
+
+  it('does not update when defeated', () => {
+    state.defeated = true;
+    const events = updateBossPhase(state, ouroboros, 10000);
+    expect(events).toHaveLength(0);
+  });
+});
+
+// ─── Phase Speedup ───────────────────────────────────────────────
+
+describe('Boss Phase Speedup', () => {
+  it('returns base duration for cycle 0', () => {
+    const duration = getEffectivePhaseDuration(
+      { cycleCount: 0 } as BossState,
+      ouroboros,
+      BossPhase.Coil,
+    );
+    expect(duration).toBe(5000);
+  });
+
+  it('reduces duration by speedup factor per cycle', () => {
+    // Cycle 1: 5000 * 0.9 = 4500
+    const duration = getEffectivePhaseDuration(
+      { cycleCount: 1 } as BossState,
+      ouroboros,
+      BossPhase.Coil,
+    );
+    expect(duration).toBeCloseTo(4500);
+  });
+
+  it('caps speedup at maxCycles', () => {
+    // Cycle 5 (maxCycles): 5000 * 0.9^5 = 2952.45
+    const duration5 = getEffectivePhaseDuration(
+      { cycleCount: 5 } as BossState,
+      ouroboros,
+      BossPhase.Coil,
+    );
+    // Cycle 10 (should cap at 5): same
+    const duration10 = getEffectivePhaseDuration(
+      { cycleCount: 10 } as BossState,
+      ouroboros,
+      BossPhase.Coil,
+    );
+    expect(duration10).toBeCloseTo(duration5);
+  });
+
+  it('applies speedup to all phases', () => {
+    const state = { cycleCount: 2 } as BossState;
+    const coil = getEffectivePhaseDuration(state, ouroboros, BossPhase.Coil);
+    const spray = getEffectivePhaseDuration(state, ouroboros, BossPhase.Spray);
+    const lash = getEffectivePhaseDuration(state, ouroboros, BossPhase.Lash);
+    const digest = getEffectivePhaseDuration(state, ouroboros, BossPhase.Digest);
+
+    expect(coil).toBeCloseTo(5000 * 0.81); // 0.9^2
+    expect(spray).toBeCloseTo(8000 * 0.81);
+    expect(lash).toBeCloseTo(6000 * 0.81);
+    expect(digest).toBeCloseTo(4000 * 0.81);
+  });
+});
+
+// ─── Armor & Regeneration ────────────────────────────────────────
+
+describe('Boss Armor and Regeneration', () => {
+  let state: BossState;
+
+  beforeEach(() => {
+    state = createBossState(ouroboros);
+  });
+
+  it('has full armor during non-vulnerable phases', () => {
+    state.currentPhase = BossPhase.Coil;
+    expect(getEffectiveArmor(state, ouroboros)).toBe(0.5);
+  });
+
+  it('has reduced armor during vulnerable phases', () => {
+    state.currentPhase = BossPhase.Digest;
+    expect(getEffectiveArmor(state, ouroboros)).toBe(0.1);
+  });
+
+  it('has full regen rate with 0 catalyst stacks', () => {
+    expect(getEffectiveRegen(state, ouroboros)).toBe(5);
+  });
+
+  it('reduces regen per catalyst stack', () => {
+    state.catalystStacks = 1;
+    expect(getEffectiveRegen(state, ouroboros)).toBe(3); // 5 - 1*2 = 3
+  });
+
+  it('regen does not go below 0', () => {
+    state.catalystStacks = 3;
+    expect(getEffectiveRegen(state, ouroboros)).toBe(0); // 5 - 3*2 = -1 → 0
+  });
+
+  it('reduces armor per catalyst stack', () => {
+    state.catalystStacks = 2;
+    state.currentPhase = BossPhase.Coil;
+    expect(getEffectiveArmor(state, ouroboros)).toBe(0.3); // 0.5 - 2*0.1
+  });
+
+  it('armor does not go below 0', () => {
+    state.catalystStacks = 10; // Way over max stacks
+    state.currentPhase = BossPhase.Digest;
+    expect(getEffectiveArmor(state, ouroboros)).toBe(0); // 0.1 - 10*0.1 → 0
+  });
+
+  it('identifies vulnerable phases correctly', () => {
+    state.currentPhase = BossPhase.Digest;
+    expect(isVulnerable(state, ouroboros)).toBe(true);
+
+    state.currentPhase = BossPhase.Coil;
+    expect(isVulnerable(state, ouroboros)).toBe(false);
+
+    state.currentPhase = BossPhase.Spray;
+    expect(isVulnerable(state, ouroboros)).toBe(false);
+
+    state.currentPhase = BossPhase.Lash;
+    expect(isVulnerable(state, ouroboros)).toBe(false);
+  });
+
+  it('applies regeneration over time', () => {
+    state.health = 250; // Damaged
+    updateBossPhase(state, ouroboros, 2000); // 2 seconds → 10 HP regen
+    expect(state.health).toBeCloseTo(260);
+  });
+
+  it('does not regenerate past max health', () => {
+    state.health = 298;
+    updateBossPhase(state, ouroboros, 2000); // Would regen 10, capped at 300
+    expect(state.health).toBe(300);
+  });
+
+  it('regeneration is reduced by catalyst stacks', () => {
+    state.health = 250;
+    state.catalystStacks = 2; // regen = 5 - 2*2 = 1 HP/s
+    updateBossPhase(state, ouroboros, 2000); // 2 seconds → 2 HP regen
+    expect(state.health).toBeCloseTo(252);
+  });
+});
+
+// ─── Damage: Direct (Victory Path 2) ────────────────────────────
+
+describe('Boss Damage — Direct', () => {
+  let state: BossState;
+
+  beforeEach(() => {
+    state = createBossState(ouroboros);
+  });
+
+  it('deals full damage during Digest (vulnerable) phase', () => {
+    state.currentPhase = BossPhase.Digest;
+    const result = applyBossDamage(state, ouroboros, 'Fe');
+    // 15 * (1 - 0.1) = 13.5 → 14 rounded
+    expect(result.damageDealt).toBe(14);
+    expect(result.damageType).toBe(VictoryMethod.Direct);
+  });
+
+  it('deals reduced damage during non-vulnerable phases', () => {
+    state.currentPhase = BossPhase.Coil;
+    const result = applyBossDamage(state, ouroboros, 'Fe');
+    // 15 * (1 - 0.5) = 7.5 → 8 rounded
+    expect(result.damageDealt).toBe(8);
+  });
+
+  it('tracks direct damage dealt', () => {
+    state.currentPhase = BossPhase.Digest;
+    applyBossDamage(state, ouroboros, 'Fe');
+    expect(state.directDamageDealt).toBeGreaterThan(0);
+    expect(state.totalDamageDealt).toBeGreaterThan(0);
+  });
+
+  it('does not deal damage to defeated boss', () => {
+    state.defeated = true;
+    const result = applyBossDamage(state, ouroboros, 'Fe');
+    expect(result.damageDealt).toBe(0);
+  });
+});
+
+// ─── Damage: Chemical (Victory Path 1) ──────────────────────────
+
+describe('Boss Damage — Chemical (NaOH)', () => {
+  let state: BossState;
+
+  beforeEach(() => {
+    state = createBossState(ouroboros);
+  });
+
+  it('deals multiplied damage with NaOH during Spray phase', () => {
+    state.currentPhase = BossPhase.Spray;
+    const result = applyBossDamage(state, ouroboros, 'NaOH');
+    // 15 * 3.0 * (1 - 0.5) = 22.5 → 23 rounded
+    expect(result.damageDealt).toBe(23);
+    expect(result.damageType).toBe(VictoryMethod.Chemical);
+  });
+
+  it('treats NaOH as normal projectile outside effective phases', () => {
+    state.currentPhase = BossPhase.Coil; // Not a chemical-effective phase
+    const result = applyBossDamage(state, ouroboros, 'NaOH');
+    // Normal reduced damage: 15 * (1 - 0.5) = 8
+    expect(result.damageDealt).toBe(8);
+    expect(result.damageType).toBe(VictoryMethod.Direct);
+  });
+
+  it('tracks chemical damage separately', () => {
+    state.currentPhase = BossPhase.Spray;
+    applyBossDamage(state, ouroboros, 'NaOH');
+    expect(state.chemicalDamageDealt).toBeGreaterThan(0);
+    expect(state.directDamageDealt).toBe(0);
+  });
+});
+
+// ─── Damage: Catalytic Poison (Victory Path 3) ──────────────────
+
+describe('Boss Damage — Catalytic Poison (Hg)', () => {
+  let state: BossState;
+
+  beforeEach(() => {
+    state = createBossState(ouroboros);
+  });
+
+  it('applies catalyst stack on first Hg hit', () => {
+    const result = applyBossDamage(state, ouroboros, 'Hg');
+    expect(result.catalystApplied).toBe(true);
+    expect(state.catalystStacks).toBe(1);
+    expect(result.damageType).toBe(VictoryMethod.Catalytic);
+  });
+
+  it('caps at maxCatalystStacks', () => {
+    state.catalystStacks = 3; // Already at max
+    const result = applyBossDamage(state, ouroboros, 'Hg');
+    expect(result.catalystApplied).toBe(false);
+    expect(state.catalystStacks).toBe(3);
+  });
+
+  it('deals damage on every Hg application', () => {
+    const result = applyBossDamage(state, ouroboros, 'Hg');
+    expect(result.damageDealt).toBeGreaterThan(0);
+  });
+
+  it('tracks catalyst damage separately', () => {
+    applyBossDamage(state, ouroboros, 'Hg');
+    expect(state.catalystDamageDealt).toBeGreaterThan(0);
+    expect(state.chemicalDamageDealt).toBe(0);
+    expect(state.directDamageDealt).toBe(0);
+  });
+
+  it('Hg works in any phase (not phase-dependent)', () => {
+    for (const phase of [BossPhase.Coil, BossPhase.Spray, BossPhase.Lash, BossPhase.Digest]) {
+      const s = createBossState(ouroboros);
+      s.currentPhase = phase;
+      const result = applyBossDamage(s, ouroboros, 'Hg');
+      expect(result.catalystApplied).toBe(true);
+      expect(result.damageType).toBe(VictoryMethod.Catalytic);
+    }
+  });
+});
+
+// ─── Victory Detection ───────────────────────────────────────────
+
+describe('Boss Victory Detection', () => {
+  let state: BossState;
+
+  beforeEach(() => {
+    state = createBossState(ouroboros);
+  });
+
+  it('detects killing blow', () => {
+    state.health = 5;
+    state.currentPhase = BossPhase.Digest;
+    const result = applyBossDamage(state, ouroboros, 'Fe');
+    expect(result.killingBlow).toBe(true);
+    expect(state.defeated).toBe(true);
+  });
+
+  it('sets victoryMethod based on killing blow type', () => {
+    state.health = 5;
+    state.currentPhase = BossPhase.Spray;
+    applyBossDamage(state, ouroboros, 'NaOH');
+    expect(state.victoryMethod).toBe(VictoryMethod.Chemical);
+  });
+
+  it('sets Catalytic victory on Hg killing blow', () => {
+    state.health = 3;
+    applyBossDamage(state, ouroboros, 'Hg');
+    expect(state.victoryMethod).toBe(VictoryMethod.Catalytic);
+  });
+
+  it('isBossDefeated returns true when defeated', () => {
+    expect(isBossDefeated(state)).toBe(false);
+    state.health = 1;
+    state.currentPhase = BossPhase.Digest;
+    applyBossDamage(state, ouroboros, 'Fe');
+    expect(isBossDefeated(state)).toBe(true);
+  });
+
+  it('health does not go below 0', () => {
+    state.health = 1;
+    state.currentPhase = BossPhase.Digest;
+    applyBossDamage(state, ouroboros, 'Fe');
+    expect(state.health).toBe(0);
+  });
+});
+
+// ─── Arena Generation ────────────────────────────────────────────
+
+describe('Arena Generation', () => {
+  it('generates a grid of correct size', () => {
+    const arena = generateArena(ouroboros, biome);
+    const diameter = ouroboros.arenaRadius * 2 + 1;
+    expect(arena.width).toBe(diameter);
+    expect(arena.height).toBe(diameter);
+    expect(arena.grid.length).toBe(diameter);
+    expect(arena.grid[0].length).toBe(diameter);
+  });
+
+  it('has walkable ground in the center', () => {
+    const arena = generateArena(ouroboros, biome);
+    const center = ouroboros.arenaRadius;
+    // Center tile should be walkable ground (0)
+    expect(arena.grid[center][center]).toBe(0);
+  });
+
+  it('has crystal wall border', () => {
+    const arena = generateArena(ouroboros, biome);
+    const r = ouroboros.arenaRadius;
+    // Top edge should be bedrock (7) or crystal (4)
+    // Very top-left corner is outside circle → bedrock
+    expect(arena.grid[0][0]).toBe(7);
+  });
+
+  it('has boss spawn at center', () => {
+    const arena = generateArena(ouroboros, biome);
+    const center = ouroboros.arenaRadius;
+    const tileSize = biome.tileSize;
+    expect(arena.bossSpawnX).toBe(center * tileSize + tileSize / 2);
+    expect(arena.bossSpawnY).toBe(center * tileSize + tileSize / 2);
+  });
+
+  it('has player spawn south of center', () => {
+    const arena = generateArena(ouroboros, biome);
+    expect(arena.playerSpawnY).toBeGreaterThan(arena.bossSpawnY);
+  });
+
+  it('places 4 resource deposits', () => {
+    const arena = generateArena(ouroboros, biome);
+    expect(arena.resourcePositions).toHaveLength(4);
+  });
+
+  it('resource positions are within arena bounds', () => {
+    const arena = generateArena(ouroboros, biome);
+    const maxPixel = arena.width * biome.tileSize;
+    for (const pos of arena.resourcePositions) {
+      expect(pos.x).toBeGreaterThan(0);
+      expect(pos.x).toBeLessThan(maxPixel);
+      expect(pos.y).toBeGreaterThan(0);
+      expect(pos.y).toBeLessThan(maxPixel);
+    }
+  });
+
+  it('has acid tiles in the arena', () => {
+    const arena = generateArena(ouroboros, biome);
+    let acidCount = 0;
+    for (const row of arena.grid) {
+      for (const tile of row) {
+        if (tile === 2) acidCount++; // ACID_SHALLOW
+      }
+    }
+    expect(acidCount).toBeGreaterThan(0);
+  });
+
+  it('buildArenaWalkableSet includes expected tiles', () => {
+    const walkable = buildArenaWalkableSet();
+    expect(walkable.has(0)).toBe(true);  // GROUND
+    expect(walkable.has(1)).toBe(true);  // SCORCHED_EARTH
+    expect(walkable.has(6)).toBe(true);  // MINERAL_VEIN
+    expect(walkable.has(7)).toBe(false); // BEDROCK (not walkable)
+    expect(walkable.has(4)).toBe(false); // CRYSTAL (not walkable)
+  });
+});
+
+// ─── Reward System ───────────────────────────────────────────────
+
+describe('Boss Reward System', () => {
+  it('calculates base reward for direct victory', () => {
+    const state = createBossState(ouroboros);
+    state.defeated = true;
+    state.victoryMethod = VictoryMethod.Direct;
+    const reward = calculateBossReward(state, ouroboros);
+    expect(reward.spores).toBe(100); // Base
+    expect(reward.loreId).toBe('ouroboros');
+    expect(reward.victoryMethod).toBe(VictoryMethod.Direct);
+  });
+
+  it('gives 50% bonus for chemical victory', () => {
+    const state = createBossState(ouroboros);
+    state.defeated = true;
+    state.victoryMethod = VictoryMethod.Chemical;
+    const reward = calculateBossReward(state, ouroboros);
+    expect(reward.spores).toBe(150); // 100 * 1.5
+  });
+
+  it('gives 100% bonus for catalytic victory', () => {
+    const state = createBossState(ouroboros);
+    state.defeated = true;
+    state.victoryMethod = VictoryMethod.Catalytic;
+    const reward = calculateBossReward(state, ouroboros);
+    expect(reward.spores).toBe(200); // 100 * 2.0
+  });
+
+  it('returns no spores if boss not defeated', () => {
+    const state = createBossState(ouroboros);
+    const reward = calculateBossReward(state, ouroboros);
+    expect(reward.spores).toBe(0);
+  });
+
+  it('includes lore text in reward', () => {
+    const state = createBossState(ouroboros);
+    state.defeated = true;
+    state.victoryMethod = VictoryMethod.Direct;
+    const reward = calculateBossReward(state, ouroboros);
+    expect(reward.loreText.length).toBeGreaterThan(0);
+    expect(reward.loreTextRu.length).toBeGreaterThan(0);
+  });
+
+  it('applyBossReward adds spores to meta', () => {
+    const meta = createMetaState();
+    const initialSpores = meta.spores;
+    const state = createBossState(ouroboros);
+    state.defeated = true;
+    state.victoryMethod = VictoryMethod.Direct;
+    const reward = calculateBossReward(state, ouroboros);
+    applyBossReward(meta, reward, 1);
+    expect(meta.spores).toBe(initialSpores + reward.spores);
+  });
+
+  it('applyBossReward adds lore to codex', () => {
+    const meta = createMetaState();
+    const state = createBossState(ouroboros);
+    state.defeated = true;
+    state.victoryMethod = VictoryMethod.Direct;
+    const reward = calculateBossReward(state, ouroboros);
+    applyBossReward(meta, reward, 1);
+    const bossEntry = meta.codex.find(e => e.id === 'ouroboros');
+    expect(bossEntry).toBeDefined();
+    expect(bossEntry?.type).toBe('boss');
+    expect(bossEntry?.discoveredOnRun).toBe(1);
+  });
+
+  it('does not add duplicate codex entries', () => {
+    const meta = createMetaState();
+    const state = createBossState(ouroboros);
+    state.defeated = true;
+    state.victoryMethod = VictoryMethod.Direct;
+    const reward = calculateBossReward(state, ouroboros);
+    applyBossReward(meta, reward, 1);
+    applyBossReward(meta, reward, 2);
+    const bossEntries = meta.codex.filter(e => e.id === 'ouroboros');
+    expect(bossEntries).toHaveLength(1);
+  });
+});
+
+// ─── Boss Entity Factory ─────────────────────────────────────────
+
+describe('Boss Entity Factory', () => {
+  let world: World;
+
+  beforeEach(() => {
+    world = createWorld();
+  });
+
+  it('creates an entity with Position component', () => {
+    const eid = createBossEntity(world, ouroboros, 400, 300);
+    expect(Position.x[eid]).toBe(400);
+    expect(Position.y[eid]).toBe(300);
+  });
+
+  it('creates an entity with Health component', () => {
+    const eid = createBossEntity(world, ouroboros, 400, 300);
+    expect(Health.current[eid]).toBe(300);
+    expect(Health.max[eid]).toBe(300);
+  });
+
+  it('creates an entity with SpriteRef component', () => {
+    const eid = createBossEntity(world, ouroboros, 400, 300);
+    expect(SpriteRef.color[eid]).toBe(0xcc44ff);
+    expect(SpriteRef.radius[eid]).toBe(20);
+  });
+
+  it('creates an entity with Boss component', () => {
+    const eid = createBossEntity(world, ouroboros, 400, 300);
+    expect(Boss.dataIndex[eid]).toBe(0);
+    expect(Boss.phase[eid]).toBe(0); // BossPhase.Coil
+    expect(Boss.cycleCount[eid]).toBe(0);
+  });
+
+  it('entity is queryable by Boss component', () => {
+    const eid = createBossEntity(world, ouroboros, 400, 300);
+    const bosses = query(world, [Boss]);
+    expect(bosses).toContain(eid);
+  });
+});
+
+// ─── Integration: Full Boss Fight ────────────────────────────────
+
+describe('Boss Fight Integration', () => {
+  it('can defeat boss with direct damage during Digest windows', () => {
+    const state = createBossState(ouroboros);
+    let totalCycles = 0;
+
+    // Simulate multiple cycles of hitting during Digest
+    // In a 4s Digest window, player can throw ~10 projectiles
+    while (!state.defeated && totalCycles < 30) {
+      // Advance through Coil → Spray → Lash → Digest
+      updateBossPhase(state, ouroboros, 5000); // Coil (+ regen)
+      updateBossPhase(state, ouroboros, 8000); // Spray (+ regen)
+      updateBossPhase(state, ouroboros, 6000); // Lash (+ regen)
+
+      // Now in Digest — rapid-fire attacks (10 per 4s window is realistic)
+      for (let i = 0; i < 10 && !state.defeated; i++) {
+        state.currentPhase = BossPhase.Digest; // Ensure in Digest
+        applyBossDamage(state, ouroboros, 'Fe');
+      }
+
+      updateBossPhase(state, ouroboros, 4000); // Complete Digest
+      totalCycles++;
+    }
+
+    expect(state.defeated).toBe(true);
+    expect(state.victoryMethod).toBe(VictoryMethod.Direct);
+    // Direct path is slow but viable (boss regens 5 HP/s between windows)
+    expect(totalCycles).toBeLessThan(30);
+  });
+
+  it('can defeat boss faster with NaOH during Spray', () => {
+    const state = createBossState(ouroboros);
+    let hits = 0;
+
+    // Advance to Spray phase and keep hitting with NaOH
+    state.currentPhase = BossPhase.Spray;
+
+    while (!state.defeated && hits < 50) {
+      applyBossDamage(state, ouroboros, 'NaOH');
+      hits++;
+    }
+
+    expect(state.defeated).toBe(true);
+    expect(state.victoryMethod).toBe(VictoryMethod.Chemical);
+    expect(hits).toBeLessThan(20); // NaOH should be efficient
+  });
+
+  it('Hg makes boss progressively weaker', () => {
+    const state = createBossState(ouroboros);
+
+    // Apply 3 Hg stacks
+    for (let i = 0; i < 3; i++) {
+      applyBossDamage(state, ouroboros, 'Hg');
+    }
+
+    expect(state.catalystStacks).toBe(3);
+    // Regen should be 0 (5 - 3*2 = -1 → 0)
+    expect(getEffectiveRegen(state, ouroboros)).toBe(0);
+    // Armor should be reduced: 0.5 - 3*0.1 = 0.2
+    expect(getEffectiveArmor(state, ouroboros)).toBeCloseTo(0.2);
+  });
+
+  it('catalyst poison + direct damage is a viable strategy', () => {
+    const state = createBossState(ouroboros);
+
+    // Apply 3 Hg stacks to maximize weakness
+    for (let i = 0; i < 3; i++) {
+      applyBossDamage(state, ouroboros, 'Hg');
+    }
+
+    // Now kill with direct damage during Digest
+    state.currentPhase = BossPhase.Digest;
+    let hits = 0;
+    while (!state.defeated && hits < 50) {
+      applyBossDamage(state, ouroboros, 'Fe');
+      hits++;
+    }
+
+    expect(state.defeated).toBe(true);
+    // Victory method should be Direct (killing blow was Fe)
+    expect(state.victoryMethod).toBe(VictoryMethod.Direct);
+  });
+});

tests/chemistry.test.ts

@@ -8,8 +8,8 @@ import { ReactionEngine } from '../src/chemistry/engine';
 // =============================================================================
 
 describe('ElementRegistry', () => {
-  it('should load all 20 elements', () => {
+  it('should load all 40 elements', () => {
-    expect(ElementRegistry.count()).toBe(20);
+    expect(ElementRegistry.count()).toBe(40);
   });
 
   it('should look up elements by symbol', () => {
@@ -59,6 +59,39 @@ describe('ElementRegistry', () => {
     expect(ElementRegistry.isElement('NaCl')).toBe(false);
     expect(ElementRegistry.isElement('H2O')).toBe(false);
   });
+
+  it('should have all 20 new Phase 9 elements', () => {
+    const newSymbols = ['Li', 'B', 'F', 'Ne', 'Ar', 'Ti', 'Cr', 'Mn', 'Co', 'Ni', 'As', 'Br', 'Ag', 'I', 'Ba', 'W', 'Pt', 'Pb', 'Bi', 'U'];
+    for (const sym of newSymbols) {
+      expect(ElementRegistry.has(sym), `Element ${sym} not found`).toBe(true);
+    }
+  });
+
+  it('should have correct data for new elements (real periodic table)', () => {
+    const li = ElementRegistry.getBySymbol('Li')!;
+    expect(li.atomicNumber).toBe(3);
+    expect(li.category).toBe('alkali-metal');
+
+    const f = ElementRegistry.getBySymbol('F')!;
+    expect(f.atomicNumber).toBe(9);
+    expect(f.category).toBe('halogen');
+    expect(f.state).toBe('gas');
+    expect(f.electronegativity).toBeCloseTo(3.98, 1); // Most electronegative
+
+    const br = ElementRegistry.getBySymbol('Br')!;
+    expect(br.state).toBe('liquid'); // Only liquid non-metal at room temp
+
+    const w = ElementRegistry.getBySymbol('W')!;
+    expect(w.atomicNumber).toBe(74);
+    expect(w.name).toBe('Tungsten');
+
+    const u = ElementRegistry.getBySymbol('U')!;
+    expect(u.atomicNumber).toBe(92);
+    expect(u.category).toBe('actinide');
+
+    const pt = ElementRegistry.getBySymbol('Pt')!;
+    expect(pt.category).toBe('transition-metal');
+  });
 });
 
 // =============================================================================
@@ -106,6 +139,32 @@ describe('CompoundRegistry', () => {
     expect(CompoundRegistry.isCompound('H2O')).toBe(true);
     expect(CompoundRegistry.isCompound('Na')).toBe(false);
   });
+
+  it('should load all 64 compounds', () => {
+    expect(CompoundRegistry.count()).toBe(64);
+  });
+
+  it('should have new Phase 9 compounds', () => {
+    const newIds = ['NH3', 'HF', 'HBr', 'TiO2', 'MnO2', 'As2O3', 'H2SO4', 'HNO3', 'CuO', 'FeCl3', 'CaCl2', 'NH4Cl', 'C6H12O6', 'CH3COOH'];
+    for (const id of newIds) {
+      expect(CompoundRegistry.has(id), `Compound ${id} not found`).toBe(true);
+    }
+  });
+
+  it('should correctly flag new dangerous compounds', () => {
+    const hf = CompoundRegistry.getById('HF')!;
+    expect(hf.properties.acidic).toBe(true);
+    expect(hf.properties.corrosive).toBe(true);
+    expect(hf.properties.toxic).toBe(true);
+
+    const h2so4 = CompoundRegistry.getById('H2SO4')!;
+    expect(h2so4.properties.acidic).toBe(true);
+    expect(h2so4.properties.oxidizer).toBe(true);
+
+    const as2o3 = CompoundRegistry.getById('As2O3')!;
+    expect(as2o3.properties.toxic).toBe(true);
+    expect(as2o3.name).toContain('Arsenic');
+  });
 });
 
 // =============================================================================
@@ -204,6 +263,104 @@ describe('ReactionEngine — success', () => {
     expect(result.reaction!.energyChange).toBeGreaterThan(0); // Endothermic
   });
 
+  it('should produce HF from H + F', () => {
+    const result = ReactionEngine.react([
+      { id: 'H', count: 1 },
+      { id: 'F', count: 1 },
+    ]);
+    expect(result.success).toBe(true);
+    expect(result.products).toEqual([{ id: 'HF', count: 1 }]);
+  });
+
+  it('should produce NH3 via Haber process (N + 3H with Fe catalyst + heat)', () => {
+    const result = ReactionEngine.react(
+      [
+        { id: 'N', count: 1 },
+        { id: 'H', count: 3 },
+      ],
+      { minTemp: 500, catalyst: 'Fe' },
+    );
+    expect(result.success).toBe(true);
+    expect(result.products).toEqual([{ id: 'NH3', count: 1 }]);
+  });
+
+  it('should produce TiO2 from Ti + 2O with extreme heat', () => {
+    const result = ReactionEngine.react(
+      [
+        { id: 'Ti', count: 1 },
+        { id: 'O', count: 2 },
+      ],
+      { minTemp: 1000 },
+    );
+    expect(result.success).toBe(true);
+    expect(result.products).toEqual([{ id: 'TiO2', count: 1 }]);
+  });
+
+  it('should produce tungsten via WO3 + Al redox', () => {
+    const result = ReactionEngine.react(
+      [
+        { id: 'WO3', count: 1 },
+        { id: 'Al', count: 2 },
+      ],
+      { minTemp: 1000 },
+    );
+    expect(result.success).toBe(true);
+    expect(result.products).toContainEqual({ id: 'W', count: 1 });
+    expect(result.products).toContainEqual({ id: 'Al2O3', count: 1 });
+  });
+
+  it('should neutralize HF with NaOH (acid-base)', () => {
+    const result = ReactionEngine.react([
+      { id: 'NaOH', count: 1 },
+      { id: 'HF', count: 1 },
+    ]);
+    expect(result.success).toBe(true);
+    expect(result.products).toContainEqual({ id: 'NaF', count: 1 });
+    expect(result.products).toContainEqual({ id: 'H2O', count: 1 });
+  });
+
+  it('should dissolve Zn in HCl (single-replacement)', () => {
+    const result = ReactionEngine.react([
+      { id: 'Zn', count: 1 },
+      { id: 'HCl', count: 2 },
+    ]);
+    expect(result.success).toBe(true);
+    expect(result.products).toContainEqual({ id: 'ZnCl2', count: 1 });
+    expect(result.products).toContainEqual({ id: 'H', count: 2 });
+  });
+
+  it('should displace Cu with Fe from CuCl2', () => {
+    const result = ReactionEngine.react([
+      { id: 'Fe', count: 1 },
+      { id: 'CuCl2', count: 1 },
+    ]);
+    expect(result.success).toBe(true);
+    expect(result.products).toContainEqual({ id: 'Cu', count: 1 });
+    expect(result.products).toContainEqual({ id: 'FeCl2', count: 1 });
+  });
+
+  it('should ferment glucose into ethanol + CO2', () => {
+    const result = ReactionEngine.react([
+      { id: 'C6H12O6', count: 1 },
+    ]);
+    expect(result.success).toBe(true);
+    expect(result.products).toContainEqual({ id: 'C2H5OH', count: 2 });
+    expect(result.products).toContainEqual({ id: 'CO2', count: 2 });
+  });
+
+  it('should produce H2SO4 via Contact process (Pt catalyst)', () => {
+    const result = ReactionEngine.react(
+      [
+        { id: 'S', count: 1 },
+        { id: 'O', count: 3 },
+        { id: 'H', count: 2 },
+      ],
+      { catalyst: 'Pt' },
+    );
+    expect(result.success).toBe(true);
+    expect(result.products).toEqual([{ id: 'H2SO4', count: 1 }]);
+  });
+
   it('reactant order should not matter (key is sorted)', () => {
     const r1 = ReactionEngine.react([
       { id: 'Cl', count: 1 },
@@ -234,6 +391,16 @@ describe('ReactionEngine — failures', () => {
     expect(result.failureReasonRu).toContain('благородный газ');
   });
 
+  it('should reject reactions with new noble gases (Ne, Ar)', () => {
+    const ne = ReactionEngine.react([{ id: 'Ne', count: 1 }, { id: 'F', count: 1 }]);
+    expect(ne.success).toBe(false);
+    expect(ne.failureReason).toContain('noble gas');
+
+    const ar = ReactionEngine.react([{ id: 'Ar', count: 1 }, { id: 'Cl', count: 1 }]);
+    expect(ar.success).toBe(false);
+    expect(ar.failureReason).toContain('noble gas');
+  });
+
   it('should reject gold reactions with explanation', () => {
     const result = ReactionEngine.react([
       { id: 'Au', count: 1 },
@@ -309,8 +476,8 @@ describe('ReactionEngine — failures', () => {
 // =============================================================================
 
 describe('ReactionEngine — metadata', () => {
-  it('should have 30+ registered reactions', () => {
+  it('should have 100+ registered reactions', () => {
-    expect(ReactionEngine.count()).toBeGreaterThanOrEqual(30);
+    expect(ReactionEngine.count()).toBeGreaterThanOrEqual(100);
   });
 
   it('should look up reactions by id', () => {

tests/crafting.test.ts

@@ -0,0 +1,189 @@
+/**
+ * Crafting System Tests — Phase 4.4
+ *
+ * Tests: crafting from inventory, reagent consumption,
+ * product addition, failure reasons, condition checks.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { Inventory } from '../src/player/inventory';
+import { craftFromInventory, type CraftInput } from '../src/player/crafting';
+
+describe('craftFromInventory — success', () => {
+  it('crafts NaCl from Na + Cl', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 3);
+    inv.addItem('Cl', 2);
+
+    const inputs: CraftInput[] = [
+      { id: 'Na', count: 1 },
+      { id: 'Cl', count: 1 },
+    ];
+    const result = craftFromInventory(inv, inputs);
+
+    expect(result.success).toBe(true);
+    expect(result.products).toContainEqual({ id: 'NaCl', count: 1 });
+    // Reagents consumed
+    expect(inv.getCount('Na')).toBe(2);
+    expect(inv.getCount('Cl')).toBe(1);
+    // Product added
+    expect(inv.getCount('NaCl')).toBe(1);
+  });
+
+  it('returns reaction data on success', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 1);
+    inv.addItem('Cl', 1);
+
+    const result = craftFromInventory(inv, [
+      { id: 'Na', count: 1 },
+      { id: 'Cl', count: 1 },
+    ]);
+
+    expect(result.success).toBe(true);
+    expect(result.reaction).toBeDefined();
+    expect(result.reaction!.id).toBe('synth_nacl');
+  });
+
+  it('reports consumed reactants', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 5);
+    inv.addItem('Cl', 5);
+
+    const inputs: CraftInput[] = [
+      { id: 'Na', count: 1 },
+      { id: 'Cl', count: 1 },
+    ];
+    const result = craftFromInventory(inv, inputs);
+
+    expect(result.consumedReactants).toEqual(inputs);
+  });
+});
+
+describe('craftFromInventory — insufficient materials', () => {
+  it('fails when missing reagent', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 1);
+    // No Cl in inventory
+
+    const result = craftFromInventory(inv, [
+      { id: 'Na', count: 1 },
+      { id: 'Cl', count: 1 },
+    ]);
+
+    expect(result.success).toBe(false);
+    expect(result.failureReason).toContain('Cl');
+    // Na not consumed
+    expect(inv.getCount('Na')).toBe(1);
+  });
+
+  it('fails when not enough of a reagent', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 1);
+    inv.addItem('Cl', 1);
+
+    const result = craftFromInventory(inv, [
+      { id: 'Na', count: 5 }, // need 5, have 1
+      { id: 'Cl', count: 1 },
+    ]);
+
+    expect(result.success).toBe(false);
+    expect(result.failureReason).toContain('Na');
+  });
+});
+
+describe('craftFromInventory — unknown reaction', () => {
+  it('fails with educational reason for no known reaction', () => {
+    const inv = new Inventory(5000); // large capacity for heavy elements
+    inv.addItem('Fe', 5);
+    inv.addItem('Au', 5);
+
+    const result = craftFromInventory(inv, [
+      { id: 'Fe', count: 1 },
+      { id: 'Au', count: 1 },
+    ]);
+
+    expect(result.success).toBe(false);
+    expect(result.failureReason).toBeDefined();
+    expect(result.failureReason!.length).toBeGreaterThan(10); // educational reason
+    // Reagents not consumed
+    expect(inv.getCount('Fe')).toBe(5);
+    expect(inv.getCount('Au')).toBe(5);
+  });
+
+  it('explains noble gas inertness', () => {
+    const inv = new Inventory();
+    inv.addItem('He', 5);
+    inv.addItem('O', 5);
+
+    const result = craftFromInventory(inv, [
+      { id: 'He', count: 1 },
+      { id: 'O', count: 1 },
+    ]);
+
+    expect(result.success).toBe(false);
+    expect(result.failureReason).toContain('noble gas');
+  });
+});
+
+describe('craftFromInventory — conditions', () => {
+  it('fails when temperature requirement not met', () => {
+    const inv = new Inventory();
+    inv.addItem('Fe', 5);
+    inv.addItem('S', 5);
+
+    // Fe + S → FeS requires minTemp: 500
+    const result = craftFromInventory(inv, [
+      { id: 'Fe', count: 1 },
+      { id: 'S', count: 1 },
+    ]);
+
+    expect(result.success).toBe(false);
+    expect(result.failureReason).toContain('temperature');
+    // Reagents not consumed
+    expect(inv.getCount('Fe')).toBe(5);
+  });
+
+  it('succeeds when conditions are met', () => {
+    const inv = new Inventory();
+    inv.addItem('Fe', 5);
+    inv.addItem('S', 5);
+
+    const result = craftFromInventory(inv, [
+      { id: 'Fe', count: 1 },
+      { id: 'S', count: 1 },
+    ], { minTemp: 500 });
+
+    expect(result.success).toBe(true);
+    expect(result.products).toContainEqual({ id: 'FeS', count: 1 });
+    expect(inv.getCount('Fe')).toBe(4);
+    expect(inv.getCount('S')).toBe(4);
+  });
+});
+
+describe('craftFromInventory — edge cases', () => {
+  it('handles empty reactants list', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 5);
+
+    const result = craftFromInventory(inv, []);
+
+    expect(result.success).toBe(false);
+  });
+
+  it('handles inventory full for products', () => {
+    const inv = new Inventory(100, 2); // Only 2 slots
+    inv.addItem('Na', 1);
+    inv.addItem('Cl', 1);
+
+    // After crafting: Na consumed (slot freed), Cl consumed (slot freed), NaCl added
+    // This should work since slots are freed before products are added
+    const result = craftFromInventory(inv, [
+      { id: 'Na', count: 1 },
+      { id: 'Cl', count: 1 },
+    ]);
+
+    expect(result.success).toBe(true);
+    expect(inv.getCount('NaCl')).toBe(1);
+  });
+});

tests/creature-interaction.test.ts

@@ -0,0 +1,306 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import { createWorld, addEntity, addComponent, query } from 'bitecs';
+import type { World } from '../src/ecs/world';
+import {
+  Position,
+  Health,
+  Creature,
+  AI,
+  Metabolism,
+  LifeCycle,
+  Projectile,
+  PlayerTag,
+  SpriteRef,
+  Velocity,
+} from '../src/ecs/components';
+import { SpeciesId, AIState, LifeStage } from '../src/creatures/types';
+import type { SpeciesData, CreatureInfo } from '../src/creatures/types';
+import { createCreatureEntity } from '../src/creatures/factory';
+import {
+  creatureProjectileSystem,
+  getObservableCreatures,
+  creatureAttackPlayerSystem,
+} from '../src/creatures/interaction';
+import type { ProjectileData } from '../src/player/projectile';
+import speciesDataArray from '../src/data/creatures.json';
+
+// ─── Helpers ─────────────────────────────────────────────────────
+
+const allSpecies = speciesDataArray as SpeciesData[];
+
+function getSpecies(id: string): SpeciesData {
+  const s = allSpecies.find(s => s.id === id);
+  if (!s) throw new Error(`Species not found: ${id}`);
+  return s;
+}
+
+function buildSpeciesLookup(): Map<number, SpeciesData> {
+  const map = new Map<number, SpeciesData>();
+  for (const s of allSpecies) map.set(s.speciesId, s);
+  return map;
+}
+
+function createProjectile(world: World, x: number, y: number, projData: Map<number, ProjectileData>): number {
+  const eid = addEntity(world);
+  addComponent(world, eid, Position);
+  addComponent(world, eid, Projectile);
+  addComponent(world, eid, SpriteRef);
+  addComponent(world, eid, Velocity);
+  Position.x[eid] = x;
+  Position.y[eid] = y;
+  Projectile.lifetime[eid] = 2000;
+  SpriteRef.color[eid] = 0xffffff;
+  SpriteRef.radius[eid] = 5;
+  projData.set(eid, { itemId: 'Na' });
+  return eid;
+}
+
+function createPlayer(world: World, x: number, y: number): number {
+  const eid = addEntity(world);
+  addComponent(world, eid, Position);
+  addComponent(world, eid, PlayerTag);
+  addComponent(world, eid, Health);
+  Position.x[eid] = x;
+  Position.y[eid] = y;
+  Health.current[eid] = 100;
+  Health.max[eid] = 100;
+  return eid;
+}
+
+// ─── Projectile-Creature Collision ───────────────────────────────
+
+describe('Projectile-Creature Collision', () => {
+  let world: World;
+  const speciesLookup = buildSpeciesLookup();
+
+  beforeEach(() => {
+    world = createWorld();
+  });
+
+  it('projectile hits creature within range', () => {
+    const species = getSpecies('crystallid');
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    const hpBefore = Health.current[creature];
+
+    const projData = new Map<number, ProjectileData>();
+    createProjectile(world, 105, 100, projData); // 5px away, within 20px hit radius
+
+    const hits = creatureProjectileSystem(world, projData, speciesLookup);
+
+    expect(hits).toHaveLength(1);
+    expect(hits[0].creatureEid).toBe(creature);
+    expect(hits[0].killed).toBe(false);
+    expect(Health.current[creature]).toBeLessThan(hpBefore);
+  });
+
+  it('projectile is removed after hitting creature', () => {
+    const species = getSpecies('crystallid');
+    createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const projData = new Map<number, ProjectileData>();
+    const projEid = createProjectile(world, 105, 100, projData);
+
+    creatureProjectileSystem(world, projData, speciesLookup);
+
+    // Projectile should be removed
+    expect(projData.has(projEid)).toBe(false);
+    expect([...query(world, [Projectile])]).not.toContain(projEid);
+  });
+
+  it('armor reduces damage (Crystallid has 0.3 armor)', () => {
+    const species = getSpecies('crystallid'); // armor = 0.3
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const projData = new Map<number, ProjectileData>();
+    createProjectile(world, 105, 100, projData);
+
+    const hits = creatureProjectileSystem(world, projData, speciesLookup);
+
+    // Base damage 15, armor 0.3 → 15 * 0.7 = 10.5 → rounded to 11
+    expect(hits[0].damage).toBe(11);
+  });
+
+  it('Reagent takes full damage (0 armor)', () => {
+    const species = getSpecies('reagent'); // armor = 0
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const projData = new Map<number, ProjectileData>();
+    createProjectile(world, 105, 100, projData);
+
+    const hits = creatureProjectileSystem(world, projData, speciesLookup);
+
+    expect(hits[0].damage).toBe(15);
+  });
+
+  it('projectile misses creature outside range', () => {
+    const species = getSpecies('crystallid');
+    createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const projData = new Map<number, ProjectileData>();
+    createProjectile(world, 200, 200, projData); // far away
+
+    const hits = creatureProjectileSystem(world, projData, speciesLookup);
+
+    expect(hits).toHaveLength(0);
+  });
+
+  it('passive creature flees after being hit', () => {
+    const species = getSpecies('crystallid'); // aggressionRadius = 0 → passive
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const projData = new Map<number, ProjectileData>();
+    createProjectile(world, 105, 100, projData);
+
+    creatureProjectileSystem(world, projData, speciesLookup);
+
+    expect(AI.state[creature]).toBe(AIState.Flee);
+  });
+
+  it('aggressive creature attacks player after being hit', () => {
+    const species = getSpecies('acidophile'); // aggressionRadius = 100 → aggressive
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    const player = createPlayer(world, 150, 100);
+
+    const projData = new Map<number, ProjectileData>();
+    createProjectile(world, 105, 100, projData);
+
+    creatureProjectileSystem(world, projData, speciesLookup);
+
+    expect(AI.state[creature]).toBe(AIState.Attack);
+    expect(AI.targetEid[creature]).toBe(player);
+  });
+
+  it('killing a creature reports killed=true', () => {
+    const species = getSpecies('reagent'); // 60 hp
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    Health.current[creature] = 10; // nearly dead
+
+    const projData = new Map<number, ProjectileData>();
+    createProjectile(world, 105, 100, projData);
+
+    const hits = creatureProjectileSystem(world, projData, speciesLookup);
+
+    expect(hits[0].killed).toBe(true);
+  });
+});
+
+// ─── Creature Observation ────────────────────────────────────────
+
+describe('Creature Observation', () => {
+  let world: World;
+
+  beforeEach(() => {
+    world = createWorld();
+  });
+
+  it('detects creature near player', () => {
+    const species = getSpecies('crystallid');
+    createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    createPlayer(world, 120, 100); // 20px away, within 60px observe range
+
+    const observations = getObservableCreatures(world);
+
+    expect(observations).toHaveLength(1);
+    expect(observations[0].speciesId).toBe(SpeciesId.Crystallid);
+    expect(observations[0].stage).toBe(LifeStage.Mature);
+  });
+
+  it('does not detect distant creature', () => {
+    const species = getSpecies('crystallid');
+    createCreatureEntity(world, species, 500, 500, LifeStage.Mature);
+    createPlayer(world, 100, 100);
+
+    const observations = getObservableCreatures(world);
+
+    expect(observations).toHaveLength(0);
+  });
+
+  it('returns health and energy percentages', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    Health.current[eid] = 60; // 50% of 120
+    Metabolism.energy[eid] = 50; // 50% of 100
+    createPlayer(world, 110, 100);
+
+    const observations = getObservableCreatures(world);
+
+    expect(observations[0].healthPercent).toBe(50);
+    expect(observations[0].energyPercent).toBe(50);
+  });
+
+  it('returns empty array when no player', () => {
+    const species = getSpecies('crystallid');
+    createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const observations = getObservableCreatures(world);
+
+    expect(observations).toHaveLength(0);
+  });
+});
+
+// ─── Creature Attacks Player ─────────────────────────────────────
+
+describe('Creature Attacks Player', () => {
+  let world: World;
+  const speciesLookup = buildSpeciesLookup();
+
+  beforeEach(() => {
+    world = createWorld();
+  });
+
+  it('attacking creature damages player in range', () => {
+    const species = getSpecies('reagent'); // attackRange = 18, damage = 20
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    const player = createPlayer(world, 110, 100); // 10px away
+
+    AI.state[creature] = AIState.Attack;
+    AI.targetEid[creature] = player;
+    AI.attackCooldown[creature] = 0;
+
+    const damage = creatureAttackPlayerSystem(world, speciesLookup);
+
+    expect(damage).toBe(20);
+    expect(Health.current[player]).toBe(80);
+  });
+
+  it('no damage if creature is out of range', () => {
+    const species = getSpecies('reagent');
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    const player = createPlayer(world, 200, 100); // 100px, beyond attackRange 18
+
+    AI.state[creature] = AIState.Attack;
+    AI.targetEid[creature] = player;
+    AI.attackCooldown[creature] = 0;
+
+    const damage = creatureAttackPlayerSystem(world, speciesLookup);
+
+    expect(damage).toBe(0);
+  });
+
+  it('attack cooldown prevents rapid attacks', () => {
+    const species = getSpecies('reagent');
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    const player = createPlayer(world, 110, 100);
+
+    AI.state[creature] = AIState.Attack;
+    AI.targetEid[creature] = player;
+    AI.attackCooldown[creature] = 500; // on cooldown
+
+    const damage = creatureAttackPlayerSystem(world, speciesLookup);
+
+    expect(damage).toBe(0);
+  });
+
+  it('non-attacking creature does not damage player', () => {
+    const species = getSpecies('crystallid');
+    const creature = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    const player = createPlayer(world, 110, 100);
+
+    AI.state[creature] = AIState.Wander; // not attacking
+    AI.attackCooldown[creature] = 0;
+
+    const damage = creatureAttackPlayerSystem(world, speciesLookup);
+
+    expect(damage).toBe(0);
+  });
+});

tests/creatures.test.ts

@@ -0,0 +1,795 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import { createWorld, addEntity, addComponent, query } from 'bitecs';
+import type { World } from '../src/ecs/world';
+import {
+  Position,
+  Velocity,
+  Health,
+  SpriteRef,
+  Creature,
+  AI,
+  Metabolism,
+  LifeCycle,
+  Resource,
+  PlayerTag,
+} from '../src/ecs/components';
+import {
+  SpeciesId,
+  AIState,
+  LifeStage,
+  SpeciesRegistry,
+} from '../src/creatures/types';
+import type { SpeciesData, CreatureInfo } from '../src/creatures/types';
+import { createCreatureEntity } from '../src/creatures/factory';
+import { aiSystem } from '../src/creatures/ai';
+import {
+  metabolismSystem,
+  resetMetabolismTracking,
+} from '../src/creatures/metabolism';
+import { lifeCycleSystem } from '../src/creatures/lifecycle';
+import { countPopulations, reproduce } from '../src/creatures/population';
+import speciesDataArray from '../src/data/creatures.json';
+
+// ─── Test Helpers ────────────────────────────────────────────────
+
+const allSpecies = speciesDataArray as SpeciesData[];
+
+function getSpecies(id: string): SpeciesData {
+  const s = allSpecies.find(s => s.id === id);
+  if (!s) throw new Error(`Species not found: ${id}`);
+  return s;
+}
+
+function buildSpeciesLookup(): Map<number, SpeciesData> {
+  const map = new Map<number, SpeciesData>();
+  for (const s of allSpecies) {
+    map.set(s.speciesId, s);
+  }
+  return map;
+}
+
+function createResourceEntity(world: World, x: number, y: number, qty: number): number {
+  const eid = addEntity(world);
+  addComponent(world, eid, Position);
+  addComponent(world, eid, Resource);
+  Position.x[eid] = x;
+  Position.y[eid] = y;
+  Resource.quantity[eid] = qty;
+  Resource.interactRange[eid] = 40;
+  return eid;
+}
+
+function createPlayerEntity(world: World, x: number, y: number): number {
+  const eid = addEntity(world);
+  addComponent(world, eid, Position);
+  addComponent(world, eid, PlayerTag);
+  Position.x[eid] = x;
+  Position.y[eid] = y;
+  return eid;
+}
+
+// ─── Species Data ────────────────────────────────────────────────
+
+describe('Species Data', () => {
+  it('loads 9 species from JSON (3 per biome)', () => {
+    expect(allSpecies).toHaveLength(9);
+  });
+
+  it('has Crystallid with correct properties', () => {
+    const c = getSpecies('crystallid');
+    expect(c.speciesId).toBe(SpeciesId.Crystallid);
+    expect(c.health).toBe(120);
+    expect(c.speed).toBe(30);
+    expect(c.armor).toBe(0.3);
+    expect(c.diet).toBe('mineral');
+    expect(c.excretionElement).toBe(14); // Si
+  });
+
+  it('has Acidophile with correct properties', () => {
+    const a = getSpecies('acidophile');
+    expect(a.speciesId).toBe(SpeciesId.Acidophile);
+    expect(a.health).toBe(80);
+    expect(a.speed).toBe(50);
+    expect(a.diet).toBe('mineral');
+    expect(a.excretionElement).toBe(17); // Cl
+  });
+
+  it('has Reagent as predator', () => {
+    const r = getSpecies('reagent');
+    expect(r.speciesId).toBe(SpeciesId.Reagent);
+    expect(r.speed).toBe(80);
+    expect(r.diet).toBe('creature');
+    expect(r.damage).toBe(20);
+  });
+
+  it('all species have valid life cycle durations', () => {
+    for (const species of allSpecies) {
+      expect(species.eggDuration).toBeGreaterThan(0);
+      expect(species.youthDuration).toBeGreaterThan(0);
+      expect(species.matureDuration).toBeGreaterThan(0);
+      expect(species.agingDuration).toBeGreaterThan(0);
+    }
+  });
+
+  it('all species have valid color hex strings', () => {
+    for (const species of allSpecies) {
+      expect(species.color).toMatch(/^#[0-9a-fA-F]{6}$/);
+    }
+  });
+});
+
+// ─── Species Registry ────────────────────────────────────────────
+
+describe('Species Registry', () => {
+  let registry: SpeciesRegistry;
+
+  beforeEach(() => {
+    registry = new SpeciesRegistry(allSpecies);
+  });
+
+  it('has correct count', () => {
+    expect(registry.count).toBe(9);
+  });
+
+  it('looks up by string ID', () => {
+    const c = registry.get('crystallid');
+    expect(c?.name).toBe('Crystallid');
+  });
+
+  it('looks up by numeric ID', () => {
+    const a = registry.getByNumericId(SpeciesId.Acidophile);
+    expect(a?.id).toBe('acidophile');
+  });
+
+  it('returns undefined for unknown ID', () => {
+    expect(registry.get('nonexistent')).toBeUndefined();
+    expect(registry.getByNumericId(99 as SpeciesId)).toBeUndefined();
+  });
+
+  it('returns all species', () => {
+    const all = registry.getAll();
+    expect(all).toHaveLength(9);
+  });
+
+  it('can look up new Phase 9 species', () => {
+    expect(registry.get('pendulum')?.biome).toBe('kinetic-mountains');
+    expect(registry.get('mechanoid')?.biome).toBe('kinetic-mountains');
+    expect(registry.get('resonator')?.biome).toBe('kinetic-mountains');
+    expect(registry.get('symbiote')?.biome).toBe('verdant-forests');
+    expect(registry.get('mimic')?.biome).toBe('verdant-forests');
+    expect(registry.get('spore-bearer')?.biome).toBe('verdant-forests');
+  });
+
+  it('each biome has exactly 3 species', () => {
+    const all = registry.getAll();
+    const byBiome = new Map<string, number>();
+    for (const s of all) {
+      byBiome.set(s.biome, (byBiome.get(s.biome) ?? 0) + 1);
+    }
+    expect(byBiome.get('catalytic-wastes')).toBe(3);
+    expect(byBiome.get('kinetic-mountains')).toBe(3);
+    expect(byBiome.get('verdant-forests')).toBe(3);
+  });
+});
+
+// ─── Creature Factory ────────────────────────────────────────────
+
+describe('Creature Factory', () => {
+  let world: World;
+
+  beforeEach(() => {
+    world = createWorld();
+  });
+
+  it('creates creature with all components', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 200);
+
+    expect(Position.x[eid]).toBe(100);
+    expect(Position.y[eid]).toBe(200);
+    expect(Creature.speciesId[eid]).toBe(SpeciesId.Crystallid);
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Egg);
+    expect(AI.state[eid]).toBe(AIState.Idle);
+    expect(Metabolism.energyMax[eid]).toBe(species.energyMax);
+  });
+
+  it('starts as egg with reduced health', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 0, 0, LifeStage.Egg);
+
+    expect(Health.current[eid]).toBe(Math.round(species.health * 0.3));
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Egg);
+    expect(SpriteRef.radius[eid]).toBe(species.radiusYouth);
+  });
+
+  it('creates mature creature with full stats', () => {
+    const species = getSpecies('acidophile');
+    const eid = createCreatureEntity(world, species, 50, 50, LifeStage.Mature);
+
+    expect(Health.current[eid]).toBe(species.health);
+    expect(Health.max[eid]).toBe(species.health);
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Mature);
+    expect(SpriteRef.radius[eid]).toBe(species.radius);
+    expect(AI.state[eid]).toBe(AIState.Wander); // mature starts wandering
+  });
+
+  it('sets home position to spawn position', () => {
+    const species = getSpecies('reagent');
+    const eid = createCreatureEntity(world, species, 300, 400);
+
+    expect(AI.homeX[eid]).toBe(300);
+    expect(AI.homeY[eid]).toBe(400);
+  });
+
+  it('sets metabolism from species data', () => {
+    const species = getSpecies('reagent');
+    const eid = createCreatureEntity(world, species, 0, 0, LifeStage.Mature);
+
+    expect(Metabolism.energyMax[eid]).toBe(species.energyMax);
+    expect(Metabolism.drainRate[eid]).toBe(species.energyDrainPerSecond);
+    expect(Metabolism.feedAmount[eid]).toBe(species.energyPerFeed);
+    expect(Metabolism.energy[eid]).toBe(species.energyMax * 0.7);
+  });
+
+  it('queries creature entities correctly', () => {
+    const s1 = getSpecies('crystallid');
+    const s2 = getSpecies('reagent');
+    const e1 = createCreatureEntity(world, s1, 0, 0);
+    const e2 = createCreatureEntity(world, s2, 100, 100);
+
+    const creatures = [...query(world, [Creature])];
+    expect(creatures).toContain(e1);
+    expect(creatures).toContain(e2);
+    expect(creatures).toHaveLength(2);
+  });
+});
+
+// ─── AI System ───────────────────────────────────────────────────
+
+describe('AI System', () => {
+  let world: World;
+  const speciesLookup = buildSpeciesLookup();
+
+  beforeEach(() => {
+    world = createWorld();
+  });
+
+  it('eggs do not move', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Egg);
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    expect(Velocity.vx[eid]).toBe(0);
+    expect(Velocity.vy[eid]).toBe(0);
+  });
+
+  it('idle creatures have zero velocity', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Idle;
+    AI.stateTimer[eid] = 5000;
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    expect(Velocity.vx[eid]).toBe(0);
+    expect(Velocity.vy[eid]).toBe(0);
+  });
+
+  it('wandering creatures have non-zero velocity', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Wander;
+    AI.stateTimer[eid] = 5000;
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    const speed = Math.sqrt(Velocity.vx[eid] ** 2 + Velocity.vy[eid] ** 2);
+    expect(speed).toBeGreaterThan(0);
+  });
+
+  it('creature flees from nearby player', () => {
+    const species = getSpecies('crystallid'); // fleeRadius = 80
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Wander;
+    AI.stateTimer[eid] = 5000;
+
+    // Place player within flee radius
+    createPlayerEntity(world, 130, 100); // 30px away, within 80
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    expect(AI.state[eid]).toBe(AIState.Flee);
+  });
+
+  it('Reagents do not flee from player', () => {
+    const species = getSpecies('reagent');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Wander;
+    AI.stateTimer[eid] = 5000;
+
+    createPlayerEntity(world, 110, 100); // very close
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    expect(AI.state[eid]).not.toBe(AIState.Flee);
+  });
+
+  it('hungry creature enters Feed state', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Wander;
+    AI.stateTimer[eid] = 5000;
+
+    // Set energy below hunger threshold
+    Metabolism.energy[eid] = species.energyMax * 0.2; // well below 0.4 threshold
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    expect(AI.state[eid]).toBe(AIState.Feed);
+  });
+
+  it('Reagent attacks nearby non-Reagent creature when hungry', () => {
+    const reagent = getSpecies('reagent');
+    const crystallid = getSpecies('crystallid');
+
+    const predator = createCreatureEntity(world, reagent, 100, 100, LifeStage.Mature);
+    const prey = createCreatureEntity(world, crystallid, 120, 100, LifeStage.Mature); // 20px away, within aggressionRadius 150
+
+    // Make predator hungry
+    Metabolism.energy[predator] = reagent.energyMax * 0.3;
+    AI.state[predator] = AIState.Wander;
+    AI.stateTimer[predator] = 5000;
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    expect(AI.state[predator]).toBe(AIState.Attack);
+    expect(AI.targetEid[predator]).toBe(prey);
+  });
+
+  it('attacking creature deals damage when in range', () => {
+    const reagent = getSpecies('reagent');
+    const crystallid = getSpecies('crystallid');
+
+    const predator = createCreatureEntity(world, reagent, 100, 100, LifeStage.Mature);
+    const prey = createCreatureEntity(world, crystallid, 110, 100, LifeStage.Mature); // 10px, within attackRange 18
+
+    const preyHpBefore = Health.current[prey];
+
+    AI.state[predator] = AIState.Attack;
+    AI.targetEid[predator] = prey;
+    AI.stateTimer[predator] = 5000;
+    AI.attackCooldown[predator] = 0;
+    Metabolism.energy[predator] = reagent.energyMax * 0.3;
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    expect(Health.current[prey]).toBeLessThan(preyHpBefore);
+  });
+
+  it('state transitions on timer expiry (idle → wander)', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Idle;
+    AI.stateTimer[eid] = 10; // almost expired
+
+    aiSystem(world, 20, speciesLookup, 1); // 20ms > 10ms timer
+
+    expect(AI.state[eid]).toBe(AIState.Wander);
+  });
+
+  it('wander → idle on timer expiry', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Wander;
+    AI.stateTimer[eid] = 10;
+
+    aiSystem(world, 20, speciesLookup, 1);
+
+    expect(AI.state[eid]).toBe(AIState.Idle);
+  });
+
+  it('creature returns to home when too far', () => {
+    const species = getSpecies('crystallid'); // wanderRadius = 200
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.homeX[eid] = 100;
+    AI.homeY[eid] = 100;
+
+    // Move creature far from home
+    Position.x[eid] = 500; // 400px away, beyond wanderRadius 200
+    Position.y[eid] = 100;
+
+    AI.state[eid] = AIState.Wander;
+    AI.stateTimer[eid] = 5000;
+
+    aiSystem(world, 16, speciesLookup, 1);
+
+    // Should be moving toward home (negative vx toward 100)
+    expect(Velocity.vx[eid]).toBeLessThan(0);
+  });
+});
+
+// ─── Metabolism System ───────────────────────────────────────────
+
+describe('Metabolism System', () => {
+  let world: World;
+  const emptyResourceData = new Map<number, { itemId: string; tileX: number; tileY: number }>();
+
+  beforeEach(() => {
+    world = createWorld();
+    resetMetabolismTracking();
+  });
+
+  it('drains energy over time', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    const energyBefore = Metabolism.energy[eid];
+
+    metabolismSystem(world, 1000, emptyResourceData, 1000); // 1 second
+
+    expect(Metabolism.energy[eid]).toBeLessThan(energyBefore);
+    expect(Metabolism.energy[eid]).toBeCloseTo(
+      energyBefore - species.energyDrainPerSecond,
+      1,
+    );
+  });
+
+  it('eggs do not metabolize', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Egg);
+    const energyBefore = Metabolism.energy[eid];
+
+    metabolismSystem(world, 1000, emptyResourceData, 1000);
+
+    expect(Metabolism.energy[eid]).toBe(energyBefore);
+  });
+
+  it('starvation deals damage when energy = 0', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    Metabolism.energy[eid] = 0;
+    const hpBefore = Health.current[eid];
+
+    metabolismSystem(world, 1000, emptyResourceData, 1000);
+
+    expect(Health.current[eid]).toBeLessThan(hpBefore);
+  });
+
+  it('creature feeds from nearby resource', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Feed;
+    Metabolism.energy[eid] = 20; // low energy
+
+    // Place resource next to creature
+    const resEid = createResourceEntity(world, 110, 100, 5);
+
+    metabolismSystem(world, 16, emptyResourceData, 5000);
+
+    // Should have gained energy
+    expect(Metabolism.energy[eid]).toBeGreaterThan(20);
+    // Resource should be depleted by 1
+    expect(Resource.quantity[resEid]).toBe(4);
+  });
+
+  it('returns excretion events after feeding', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Feed;
+    Metabolism.energy[eid] = 20;
+
+    createResourceEntity(world, 110, 100, 5);
+
+    const excretions = metabolismSystem(world, 16, emptyResourceData, 5000);
+
+    expect(excretions.length).toBeGreaterThan(0);
+    expect(excretions[0][0]).toBe(eid); // creature eid
+    expect(excretions[0][1]).toBe(SpeciesId.Crystallid);
+  });
+
+  it('energy does not exceed max', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    AI.state[eid] = AIState.Feed;
+    Metabolism.energy[eid] = species.energyMax - 1; // almost full
+
+    createResourceEntity(world, 110, 100, 5);
+
+    metabolismSystem(world, 16, emptyResourceData, 5000);
+
+    expect(Metabolism.energy[eid]).toBe(species.energyMax);
+  });
+
+  it('youth drains energy slower (0.7x)', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Youth);
+    const energyBefore = Metabolism.energy[eid];
+
+    metabolismSystem(world, 1000, emptyResourceData, 1000);
+
+    const drained = energyBefore - Metabolism.energy[eid];
+    expect(drained).toBeCloseTo(species.energyDrainPerSecond * 0.7, 1);
+  });
+
+  it('aging drains energy faster (1.3x)', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Aging);
+    const energyBefore = Metabolism.energy[eid];
+
+    metabolismSystem(world, 1000, emptyResourceData, 1000);
+
+    const drained = energyBefore - Metabolism.energy[eid];
+    expect(drained).toBeCloseTo(species.energyDrainPerSecond * 1.3, 1);
+  });
+});
+
+// ─── Life Cycle System ───────────────────────────────────────────
+
+describe('Life Cycle System', () => {
+  let world: World;
+  const speciesLookup = buildSpeciesLookup();
+
+  beforeEach(() => {
+    world = createWorld();
+  });
+
+  it('advances age over time', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    lifeCycleSystem(world, 1000, speciesLookup);
+
+    expect(LifeCycle.age[eid]).toBe(1000);
+  });
+
+  it('egg hatches to youth when timer expires', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Egg);
+
+    // Fast-forward past egg duration
+    const events = lifeCycleSystem(world, species.eggDuration + 100, speciesLookup);
+
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Youth);
+    expect(events.some(e => e.type === 'stage_advance' && e.newStage === LifeStage.Youth)).toBe(true);
+  });
+
+  it('youth grows to mature', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Youth);
+
+    const events = lifeCycleSystem(world, species.youthDuration + 100, speciesLookup);
+
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Mature);
+    expect(Health.current[eid]).toBe(species.health); // full health
+    expect(SpriteRef.radius[eid]).toBe(species.radius); // full size
+    expect(events.some(e => e.type === 'stage_advance' && e.newStage === LifeStage.Mature)).toBe(true);
+  });
+
+  it('mature ages to aging', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const events = lifeCycleSystem(world, species.matureDuration + 100, speciesLookup);
+
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Aging);
+    expect(Health.max[eid]).toBe(Math.round(species.health * 0.7)); // reduced
+    expect(events.some(e => e.type === 'stage_advance' && e.newStage === LifeStage.Aging)).toBe(true);
+  });
+
+  it('aging leads to natural death', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Aging);
+
+    const events = lifeCycleSystem(world, species.agingDuration + 100, speciesLookup);
+
+    expect(Health.current[eid]).toBe(0);
+    expect(events.some(e => e.type === 'natural_death')).toBe(true);
+  });
+
+  it('reports ready_to_reproduce for mature creatures with high energy', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+    Metabolism.energy[eid] = species.energyMax * 0.9; // above 0.8 threshold
+
+    // Don't let timer expire
+    LifeCycle.stageTimer[eid] = 99999;
+
+    const events = lifeCycleSystem(world, 100, speciesLookup);
+
+    expect(events.some(e => e.type === 'ready_to_reproduce' && e.eid === eid)).toBe(true);
+  });
+
+  it('does not report reproduction for youth', () => {
+    const species = getSpecies('crystallid');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Youth);
+    Metabolism.energy[eid] = species.energyMax; // full energy but youth
+
+    LifeCycle.stageTimer[eid] = 99999;
+
+    const events = lifeCycleSystem(world, 100, speciesLookup);
+
+    expect(events.some(e => e.type === 'ready_to_reproduce' && e.eid === eid)).toBe(false);
+  });
+
+  it('full lifecycle: egg → youth → mature → aging → death', () => {
+    const species = getSpecies('acidophile');
+    const eid = createCreatureEntity(world, species, 100, 100, LifeStage.Egg);
+
+    // Egg → Youth
+    lifeCycleSystem(world, species.eggDuration + 1, speciesLookup);
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Youth);
+
+    // Youth → Mature
+    lifeCycleSystem(world, species.youthDuration + 1, speciesLookup);
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Mature);
+
+    // Mature → Aging
+    lifeCycleSystem(world, species.matureDuration + 1, speciesLookup);
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Aging);
+
+    // Aging → Death
+    const events = lifeCycleSystem(world, species.agingDuration + 1, speciesLookup);
+    expect(Health.current[eid]).toBe(0);
+    expect(events.some(e => e.type === 'natural_death')).toBe(true);
+  });
+});
+
+// ─── Population Dynamics ─────────────────────────────────────────
+
+describe('Population Dynamics', () => {
+  let world: World;
+
+  beforeEach(() => {
+    world = createWorld();
+  });
+
+  it('counts populations correctly', () => {
+    const s1 = getSpecies('crystallid');
+    const s2 = getSpecies('reagent');
+
+    createCreatureEntity(world, s1, 0, 0, LifeStage.Mature);
+    createCreatureEntity(world, s1, 100, 0, LifeStage.Mature);
+    createCreatureEntity(world, s2, 200, 0, LifeStage.Mature);
+
+    const counts = countPopulations(world);
+
+    expect(counts.get(SpeciesId.Crystallid)).toBe(2);
+    expect(counts.get(SpeciesId.Reagent)).toBe(1);
+    expect(counts.get(SpeciesId.Acidophile)).toBeUndefined();
+  });
+
+  it('reproduce creates offspring near parent', () => {
+    const species = getSpecies('crystallid'); // offspringCount = 2
+    const parent = createCreatureEntity(world, species, 200, 200, LifeStage.Mature);
+
+    const creatureData = new Map<number, CreatureInfo>();
+    const newEids = reproduce(world, parent, species, 1, creatureData);
+
+    expect(newEids).toHaveLength(2);
+
+    for (const eid of newEids) {
+      // Offspring should be eggs near parent
+      expect(LifeCycle.stage[eid]).toBe(LifeStage.Egg);
+      const dx = Math.abs(Position.x[eid] - 200);
+      const dy = Math.abs(Position.y[eid] - 200);
+      expect(dx).toBeLessThanOrEqual(25);
+      expect(dy).toBeLessThanOrEqual(25);
+
+      // Should be tracked in creature data
+      expect(creatureData.has(eid)).toBe(true);
+    }
+  });
+
+  it('reproduce respects population cap', () => {
+    const species = getSpecies('reagent'); // maxPopulation = 8, offspringCount = 1
+    const parent = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const creatureData = new Map<number, CreatureInfo>();
+
+    // At max population
+    const newEids = reproduce(world, parent, species, 8, creatureData);
+    expect(newEids).toHaveLength(0);
+  });
+
+  it('reproduce limits offspring to not exceed cap', () => {
+    const species = getSpecies('crystallid'); // maxPopulation = 12, offspringCount = 2
+    const parent = createCreatureEntity(world, species, 100, 100, LifeStage.Mature);
+
+    const creatureData = new Map<number, CreatureInfo>();
+
+    // Population at 11, only room for 1 offspring
+    const newEids = reproduce(world, parent, species, 11, creatureData);
+    expect(newEids).toHaveLength(1);
+  });
+});
+
+// ─── Integration ─────────────────────────────────────────────────
+
+describe('Creature Integration', () => {
+  let world: World;
+  const speciesLookup = buildSpeciesLookup();
+
+  beforeEach(() => {
+    world = createWorld();
+    resetMetabolismTracking();
+  });
+
+  it('creature lifecycle: hatch → feed → reproduce → age → die', () => {
+    const species = getSpecies('acidophile');
+    const eid = createCreatureEntity(world, species, 200, 200, LifeStage.Egg);
+
+    // 1. Hatch
+    lifeCycleSystem(world, species.eggDuration + 1, speciesLookup);
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Youth);
+
+    // 2. Grow to mature
+    lifeCycleSystem(world, species.youthDuration + 1, speciesLookup);
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Mature);
+
+    // 3. AI works — creature wanders
+    aiSystem(world, 16, speciesLookup, 1);
+    const speed = Math.sqrt(Velocity.vx[eid] ** 2 + Velocity.vy[eid] ** 2);
+    expect(speed).toBeGreaterThan(0);
+
+    // 4. Metabolism drains energy
+    const energyBefore = Metabolism.energy[eid];
+    metabolismSystem(world, 1000, new Map(), 10000);
+    expect(Metabolism.energy[eid]).toBeLessThan(energyBefore);
+
+    // 5. Age to aging
+    lifeCycleSystem(world, species.matureDuration + 1, speciesLookup);
+    expect(LifeCycle.stage[eid]).toBe(LifeStage.Aging);
+
+    // 6. Natural death
+    const events = lifeCycleSystem(world, species.agingDuration + 1, speciesLookup);
+    expect(events.some(e => e.type === 'natural_death')).toBe(true);
+  });
+
+  it('predator-prey interaction: reagent kills crystallid', () => {
+    const reagent = getSpecies('reagent');
+    const crystallid = getSpecies('crystallid');
+
+    const pred = createCreatureEntity(world, reagent, 100, 100, LifeStage.Mature);
+    const prey = createCreatureEntity(world, crystallid, 110, 100, LifeStage.Mature);
+
+    // Set predator to attack
+    AI.state[pred] = AIState.Attack;
+    AI.targetEid[pred] = prey;
+    AI.stateTimer[pred] = 10000;
+    AI.attackCooldown[pred] = 0;
+    Metabolism.energy[pred] = reagent.energyMax * 0.3;
+
+    const initialHp = Health.current[prey];
+
+    // Simulate several attack cycles
+    for (let i = 0; i < 20; i++) {
+      aiSystem(world, 1000, speciesLookup, i);
+      AI.attackCooldown[pred] = 0; // reset cooldown for test
+    }
+
+    expect(Health.current[prey]).toBeLessThanOrEqual(0);
+  });
+
+  it('creature ecosystem with multiple species runs without errors', () => {
+    const species = allSpecies;
+
+    // Spawn several of each
+    for (const s of species) {
+      for (let i = 0; i < 3; i++) {
+        createCreatureEntity(world, s, 100 + i * 50, 100 + s.speciesId * 100, LifeStage.Mature);
+      }
+    }
+
+    // Run 100 ticks
+    for (let tick = 0; tick < 100; tick++) {
+      aiSystem(world, 16, speciesLookup, tick);
+      metabolismSystem(world, 16, new Map(), tick * 16);
+      lifeCycleSystem(world, 16, speciesLookup);
+    }
+
+    // Should still have creatures alive
+    const counts = countPopulations(world);
+    const total = [...counts.values()].reduce((a, b) => a + b, 0);
+    expect(total).toBeGreaterThan(0);
+  });
+});

tests/ecosystem.test.ts

@@ -0,0 +1,280 @@
+/**
+ * Ecosystem Test — verify populations fluctuate without dying out
+ *
+ * Runs a headless simulation with all creature systems active,
+ * no player present. Verifies:
+ * - Populations oscillate (Lotka-Volterra dynamics)
+ * - No species goes fully extinct within the test window
+ * - Reproduction keeps populations alive
+ * - Predation reduces prey population
+ */
+
+import { describe, it, expect, beforeEach } from 'vitest';
+import { createWorld, addEntity, addComponent, query } from 'bitecs';
+import type { World } from '../src/ecs/world';
+import { Position, Resource, Creature, Health, Metabolism, LifeCycle, AI } from '../src/ecs/components';
+import { SpeciesId, LifeStage, AIState } from '../src/creatures/types';
+import type { SpeciesData, CreatureInfo } from '../src/creatures/types';
+import { createCreatureEntity } from '../src/creatures/factory';
+import { aiSystem } from '../src/creatures/ai';
+import { metabolismSystem, resetMetabolismTracking } from '../src/creatures/metabolism';
+import { lifeCycleSystem } from '../src/creatures/lifecycle';
+import { countPopulations, reproduce } from '../src/creatures/population';
+import { movementSystem } from '../src/ecs/systems/movement';
+import { healthSystem } from '../src/ecs/systems/health';
+import { removeGameEntity } from '../src/ecs/factory';
+import speciesDataArray from '../src/data/creatures.json';
+
+// ─── Helpers ─────────────────────────────────────────────────────
+
+const allSpecies = speciesDataArray as SpeciesData[];
+
+function getSpecies(id: string): SpeciesData {
+  const s = allSpecies.find(s => s.id === id);
+  if (!s) throw new Error(`Species not found: ${id}`);
+  return s;
+}
+
+function buildSpeciesLookup(): Map<number, SpeciesData> {
+  const map = new Map<number, SpeciesData>();
+  for (const s of allSpecies) map.set(s.speciesId, s);
+  return map;
+}
+
+function createResourceField(world: World, count: number): void {
+  for (let i = 0; i < count; i++) {
+    const eid = addEntity(world);
+    addComponent(world, eid, Position);
+    addComponent(world, eid, Resource);
+    Position.x[eid] = (i % 10) * 50 + 25;
+    Position.y[eid] = Math.floor(i / 10) * 50 + 25;
+    Resource.quantity[eid] = 999; // infinite for ecosystem test
+    Resource.interactRange[eid] = 40;
+  }
+}
+
+/**
+ * Run one simulation tick.
+ * Mimics what GameScene.update() does, minus Phaser-specific parts.
+ */
+function simulateTick(
+  world: World,
+  deltaMs: number,
+  speciesLookup: Map<number, SpeciesData>,
+  tick: number,
+  creatureData: Map<number, CreatureInfo>,
+): void {
+  const elapsed = tick * deltaMs;
+
+  // AI
+  aiSystem(world, deltaMs, speciesLookup, tick);
+
+  // Movement
+  movementSystem(world, deltaMs);
+
+  // Metabolism
+  metabolismSystem(world, deltaMs, new Map(), elapsed);
+
+  // Life cycle
+  const lcEvents = lifeCycleSystem(world, deltaMs, speciesLookup);
+
+  // Reproduction
+  const populations = countPopulations(world);
+  for (const event of lcEvents) {
+    if (event.type === 'ready_to_reproduce') {
+      const species = speciesLookup.get(event.speciesId);
+      if (species) {
+        const currentPop = populations.get(event.speciesId) ?? 0;
+        reproduce(world, event.eid, species, currentPop, creatureData);
+      }
+    }
+  }
+
+  // Health / death
+  const dead = healthSystem(world);
+  for (const eid of dead) {
+    creatureData.delete(eid);
+    removeGameEntity(world, eid);
+  }
+}
+
+// ─── Ecosystem Tests ─────────────────────────────────────────────
+
+describe('Ecosystem Simulation', () => {
+  let world: World;
+  const speciesLookup = buildSpeciesLookup();
+  const DELTA = 100; // 100ms per tick (10 fps for speed)
+
+  beforeEach(() => {
+    world = createWorld();
+    resetMetabolismTracking();
+  });
+
+  it('single species population stabilizes with food', () => {
+    const species = getSpecies('crystallid');
+    const creatureData = new Map<number, CreatureInfo>();
+
+    // Spawn 5 mature Crystallids
+    for (let i = 0; i < 5; i++) {
+      const eid = createCreatureEntity(
+        world, species, 50 + i * 40, 50, LifeStage.Mature,
+      );
+      // Give them plenty of energy so they can reproduce
+      Metabolism.energy[eid] = species.energyMax;
+      creatureData.set(eid, { speciesId: species.speciesId, speciesDataId: species.id });
+    }
+
+    // Abundant food
+    createResourceField(world, 30);
+
+    // Simulate 200 ticks (20 seconds game time)
+    const populationHistory: number[] = [];
+    for (let t = 0; t < 200; t++) {
+      simulateTick(world, DELTA, speciesLookup, t, creatureData);
+      if (t % 10 === 0) {
+        const counts = countPopulations(world);
+        populationHistory.push(counts.get(SpeciesId.Crystallid) ?? 0);
+      }
+    }
+
+    // Population should not die out
+    const finalCount = countPopulations(world).get(SpeciesId.Crystallid) ?? 0;
+    expect(finalCount).toBeGreaterThan(0);
+
+    // Population should have some variation (not flat)
+    const min = Math.min(...populationHistory);
+    const max = Math.max(...populationHistory);
+    // At minimum, we should have had some births (max > initial 5)
+    expect(max).toBeGreaterThanOrEqual(5);
+  });
+
+  it('predator-prey dynamics: reagents reduce prey population', () => {
+    const crystallid = getSpecies('crystallid');
+    const reagent = getSpecies('reagent');
+    const creatureData = new Map<number, CreatureInfo>();
+
+    // Spawn prey
+    for (let i = 0; i < 6; i++) {
+      const eid = createCreatureEntity(
+        world, crystallid, 100 + i * 30, 100, LifeStage.Mature,
+      );
+      Metabolism.energy[eid] = crystallid.energyMax;
+      creatureData.set(eid, { speciesId: crystallid.speciesId, speciesDataId: crystallid.id });
+    }
+
+    // Spawn predators
+    for (let i = 0; i < 3; i++) {
+      const eid = createCreatureEntity(
+        world, reagent, 100 + i * 30, 130, LifeStage.Mature,
+      );
+      Metabolism.energy[eid] = reagent.energyMax * 0.3; // hungry!
+      creatureData.set(eid, { speciesId: reagent.speciesId, speciesDataId: reagent.id });
+    }
+
+    createResourceField(world, 20);
+
+    // Record initial prey count
+    const initialPrey = countPopulations(world).get(SpeciesId.Crystallid) ?? 0;
+    expect(initialPrey).toBe(6);
+
+    // Simulate for a while — predators should hunt
+    for (let t = 0; t < 300; t++) {
+      simulateTick(world, DELTA, speciesLookup, t, creatureData);
+    }
+
+    // Some prey should have been killed by predators
+    const finalPrey = countPopulations(world).get(SpeciesId.Crystallid) ?? 0;
+    // Either prey died from predation/aging, or reproduced
+    // The key check: something happened (population changed)
+    const totalCreatures = [...countPopulations(world).values()].reduce((a, b) => a + b, 0);
+    expect(totalCreatures).toBeGreaterThan(0); // ecosystem still alive
+  });
+
+  it('starvation without food leads to population decline', () => {
+    const species = getSpecies('acidophile');
+    const creatureData = new Map<number, CreatureInfo>();
+
+    // Spawn creatures with low energy and NO food sources
+    for (let i = 0; i < 5; i++) {
+      const eid = createCreatureEntity(
+        world, species, 50 + i * 40, 50, LifeStage.Mature,
+      );
+      Metabolism.energy[eid] = 10; // very low energy, no food available
+      creatureData.set(eid, { speciesId: species.speciesId, speciesDataId: species.id });
+    }
+
+    // NO food! Simulate starvation (need ~25s for full drain + death at 100ms/tick)
+    for (let t = 0; t < 300; t++) {
+      simulateTick(world, DELTA, speciesLookup, t, creatureData);
+    }
+
+    // Population should decline due to starvation
+    const finalCount = countPopulations(world).get(SpeciesId.Acidophile) ?? 0;
+    expect(finalCount).toBeLessThan(5);
+  });
+
+  it('mixed ecosystem runs without errors for 500 ticks', () => {
+    const creatureData = new Map<number, CreatureInfo>();
+
+    // Spawn a balanced mix
+    for (const species of allSpecies) {
+      const count = species.id === 'reagent' ? 2 : 4;
+      for (let i = 0; i < count; i++) {
+        const eid = createCreatureEntity(
+          world, species,
+          50 + i * 60 + species.speciesId * 200,
+          50 + species.speciesId * 100,
+          LifeStage.Mature,
+        );
+        Metabolism.energy[eid] = species.energyMax * 0.8;
+        creatureData.set(eid, { speciesId: species.speciesId, speciesDataId: species.id });
+      }
+    }
+
+    createResourceField(world, 40);
+
+    // Run 500 ticks — should not throw
+    for (let t = 0; t < 500; t++) {
+      simulateTick(world, DELTA, speciesLookup, t, creatureData);
+    }
+
+    // At least some creatures should survive
+    const total = [...countPopulations(world).values()].reduce((a, b) => a + b, 0);
+    expect(total).toBeGreaterThan(0);
+  });
+
+  it('lifecycle drives population renewal', () => {
+    const species = getSpecies('acidophile');
+    const creatureData = new Map<number, CreatureInfo>();
+
+    // Start with eggs — they should hatch, grow, reproduce
+    for (let i = 0; i < 4; i++) {
+      const eid = createCreatureEntity(
+        world, species, 50 + i * 30, 50, LifeStage.Egg,
+      );
+      creatureData.set(eid, { speciesId: species.speciesId, speciesDataId: species.id });
+    }
+
+    createResourceField(world, 20);
+
+    // Run long enough for eggs to hatch and creatures to mature
+    // egg(6s) + youth(12s) = 18s → need 180 ticks at 100ms/tick
+    for (let t = 0; t < 250; t++) {
+      simulateTick(world, DELTA, speciesLookup, t, creatureData);
+    }
+
+    // Should have some mature creatures (eggs hatched and grew)
+    const allCreatures = query(world, [Creature, LifeCycle]);
+    let hasMature = false;
+    for (const eid of allCreatures) {
+      if (LifeCycle.stage[eid] === LifeStage.Mature || LifeCycle.stage[eid] === LifeStage.Aging) {
+        hasMature = true;
+        break;
+      }
+    }
+
+    // Either has mature creatures or population renewed
+    const total = countPopulations(world).get(SpeciesId.Acidophile) ?? 0;
+    expect(total).toBeGreaterThan(0);
+  });
+});

tests/escalation.test.ts

@@ -0,0 +1,147 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import type { RunState } from '../src/run/types';
+import { RunPhase, ESCALATION_RATE } from '../src/run/types';
+import { createRunState, advancePhase, updateEscalation } from '../src/run/state';
+import {
+  getEscalationEffects,
+  type EscalationEffects,
+} from '../src/run/escalation';
+import {
+  createCrisisState,
+  applyCrisisDamage,
+  attemptNeutralize,
+  isCrisisResolved,
+  getCrisisPlayerDamage,
+  getCrisisTint,
+  CHEMICAL_PLAGUE,
+} from '../src/run/crisis';
+
+// ─── Escalation Effects ──────────────────────────────────────────
+
+describe('Escalation Effects', () => {
+  it('at 0 escalation, all multipliers are 1.0', () => {
+    const fx = getEscalationEffects(0);
+    expect(fx.creatureSpeedMultiplier).toBe(1.0);
+    expect(fx.creatureAggroRange).toBe(1.0);
+    expect(fx.creatureAttackMultiplier).toBe(1.0);
+    expect(fx.reactionInstability).toBe(0);
+    expect(fx.environmentalDamage).toBe(0);
+  });
+
+  it('at 0.5 escalation, effects are moderate', () => {
+    const fx = getEscalationEffects(0.5);
+    expect(fx.creatureSpeedMultiplier).toBeGreaterThan(1.0);
+    expect(fx.creatureSpeedMultiplier).toBeLessThan(2.0);
+    expect(fx.creatureAggroRange).toBeGreaterThan(1.0);
+    expect(fx.creatureAttackMultiplier).toBeGreaterThan(1.0);
+    expect(fx.reactionInstability).toBeGreaterThan(0);
+  });
+
+  it('at 1.0 escalation, effects are maximal', () => {
+    const fx = getEscalationEffects(1.0);
+    expect(fx.creatureSpeedMultiplier).toBe(1.5);
+    expect(fx.creatureAggroRange).toBe(1.8);
+    expect(fx.creatureAttackMultiplier).toBe(1.6);
+    expect(fx.reactionInstability).toBe(0.3);
+    expect(fx.environmentalDamage).toBeGreaterThan(0);
+  });
+
+  it('escalation clamps values correctly', () => {
+    const fx = getEscalationEffects(2.0); // over max
+    expect(fx.creatureSpeedMultiplier).toBe(1.5);
+
+    const fxNeg = getEscalationEffects(-1.0); // under min
+    expect(fxNeg.creatureSpeedMultiplier).toBe(1.0);
+  });
+});
+
+// ─── Crisis Damage ───────────────────────────────────────────────
+
+describe('Crisis Player Damage', () => {
+  it('no damage below 30% progress', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.2;
+    expect(getCrisisPlayerDamage(crisis, 1000)).toBe(0);
+  });
+
+  it('damage increases with progress above 30%', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.5;
+    const dmg = getCrisisPlayerDamage(crisis, 1000);
+    expect(dmg).toBeGreaterThan(0);
+  });
+
+  it('damage scales with delta time', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.8;
+    const dmg1 = getCrisisPlayerDamage(crisis, 1000);
+    const dmg2 = getCrisisPlayerDamage(crisis, 2000);
+    expect(dmg2).toBeCloseTo(dmg1 * 2, 1);
+  });
+
+  it('no damage when resolved', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.8;
+    crisis.resolved = true;
+    expect(getCrisisPlayerDamage(crisis, 1000)).toBe(0);
+  });
+});
+
+describe('Crisis Visual Tint', () => {
+  it('returns no tint at 0 progress', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0;
+    const tint = getCrisisTint(crisis);
+    expect(tint.alpha).toBe(0);
+  });
+
+  it('returns tint at high progress', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.8;
+    const tint = getCrisisTint(crisis);
+    expect(tint.alpha).toBeGreaterThan(0);
+    expect(tint.color).toBeDefined();
+  });
+
+  it('returns no tint when resolved', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.8;
+    crisis.resolved = true;
+    const tint = getCrisisTint(crisis);
+    expect(tint.alpha).toBe(0);
+  });
+});
+
+// ─── Escalation-Phase Integration ────────────────────────────────
+
+describe('Escalation Integration', () => {
+  let state: RunState;
+
+  beforeEach(() => {
+    state = createRunState(1, 'alchemist');
+    state.phase = RunPhase.Escalation;
+  });
+
+  it('escalation grows steadily over time', () => {
+    // Simulate 30 seconds
+    for (let i = 0; i < 30; i++) {
+      updateEscalation(state, 1000);
+    }
+    expect(state.escalation).toBeCloseTo(ESCALATION_RATE * 30, 2);
+  });
+
+  it('effects scale linearly with escalation', () => {
+    updateEscalation(state, 100_000); // ~100 seconds
+    const fx = getEscalationEffects(state.escalation);
+    expect(fx.creatureSpeedMultiplier).toBeGreaterThan(1.0);
+    expect(fx.creatureAggroRange).toBeGreaterThan(1.0);
+  });
+
+  it('full escalation cycle reaches crisis threshold', () => {
+    // Simulate until threshold
+    for (let i = 0; i < 200; i++) {
+      updateEscalation(state, 1000);
+    }
+    expect(state.escalation).toBeGreaterThanOrEqual(CHEMICAL_PLAGUE.triggerThreshold);
+  });
+});

tests/great-cycle.test.ts

@@ -0,0 +1,469 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import type { MetaState, RunState, GreatCycleState, RunTrace } from '../src/run/types';
+import {
+  CYCLE_THEMES,
+  CYCLE_THEME_NAMES,
+  CYCLE_THEME_NAMES_RU,
+  RUNS_PER_CYCLE,
+  RunPhase,
+} from '../src/run/types';
+import {
+  createGreatCycleState,
+  getCycleTheme,
+  createRunTrace,
+  recordRunAndAdvanceCycle,
+  performGreatRenewal,
+  getCycleWorldModifiers,
+  getTracesForBiome,
+  getDeathTraces,
+  isLastRunInCycle,
+  getCycleSummary,
+} from '../src/run/cycle';
+import { createMetaState, applyRunResults } from '../src/run/meta';
+import { createRunState, recordDiscovery } from '../src/run/state';
+import narrativeData from '../src/data/cycle-narrative.json';
+
+// ─── Great Cycle Initialization ──────────────────────────────────
+
+describe('Great Cycle Initialization', () => {
+  it('should create initial cycle state at cycle 1, run 1', () => {
+    const state = createGreatCycleState();
+    expect(state.cycleNumber).toBe(1);
+    expect(state.runInCycle).toBe(1);
+    expect(state.theme).toBe('awakening');
+    expect(state.currentCycleTraces).toEqual([]);
+    expect(state.previousCycleTraces).toEqual([]);
+    expect(state.renewalsCompleted).toBe(0);
+    expect(state.myceliumMaturation).toBe(0);
+  });
+
+  it('MetaState should include greatCycle on creation', () => {
+    const meta = createMetaState();
+    expect(meta.greatCycle).toBeDefined();
+    expect(meta.greatCycle.cycleNumber).toBe(1);
+    expect(meta.greatCycle.runInCycle).toBe(1);
+    expect(meta.greatCycle.theme).toBe('awakening');
+  });
+});
+
+// ─── Cycle Theme Resolution ─────────────────────────────────────
+
+describe('Cycle Theme Resolution', () => {
+  it('should have 6 predefined themes', () => {
+    expect(CYCLE_THEMES.length).toBe(6);
+  });
+
+  it('should return correct theme for each cycle number', () => {
+    expect(getCycleTheme(1)).toBe('awakening');
+    expect(getCycleTheme(2)).toBe('doubt');
+    expect(getCycleTheme(3)).toBe('realization');
+    expect(getCycleTheme(4)).toBe('attempt');
+    expect(getCycleTheme(5)).toBe('acceptance');
+    expect(getCycleTheme(6)).toBe('synthesis');
+  });
+
+  it('cycles beyond 6 should use synthesis theme', () => {
+    expect(getCycleTheme(7)).toBe('synthesis');
+    expect(getCycleTheme(10)).toBe('synthesis');
+    expect(getCycleTheme(100)).toBe('synthesis');
+  });
+
+  it('invalid cycle numbers default to awakening', () => {
+    expect(getCycleTheme(0)).toBe('awakening');
+    expect(getCycleTheme(-1)).toBe('awakening');
+  });
+
+  it('all themes have Russian and English names', () => {
+    for (const theme of CYCLE_THEMES) {
+      expect(CYCLE_THEME_NAMES[theme]).toBeDefined();
+      expect(CYCLE_THEME_NAMES[theme].length).toBeGreaterThan(0);
+      expect(CYCLE_THEME_NAMES_RU[theme]).toBeDefined();
+      expect(CYCLE_THEME_NAMES_RU[theme].length).toBeGreaterThan(0);
+    }
+  });
+});
+
+// ─── Run Trace Recording ─────────────────────────────────────────
+
+describe('Run Trace Recording', () => {
+  let meta: MetaState;
+
+  beforeEach(() => {
+    meta = createMetaState();
+  });
+
+  function makeCompletedRun(overrides?: Partial<RunState>): RunState {
+    const run = createRunState(1, 'alchemist', 'catalytic-wastes', 42);
+    run.phase = RunPhase.Resolution;
+    run.elapsed = 120000;
+    run.crisisResolved = true;
+    run.deathPosition = { tileX: 30, tileY: 40 };
+    recordDiscovery(run, 'element', 'Na');
+    recordDiscovery(run, 'element', 'O');
+    recordDiscovery(run, 'reaction', 'Na+Cl');
+    if (overrides) Object.assign(run, overrides);
+    return run;
+  }
+
+  it('should create a trace from completed run', () => {
+    const run = makeCompletedRun();
+    const trace = createRunTrace(run, meta.greatCycle);
+    expect(trace.runId).toBe(1);
+    expect(trace.runInCycle).toBe(1);
+    expect(trace.schoolId).toBe('alchemist');
+    expect(trace.biomeId).toBe('catalytic-wastes');
+    expect(trace.deathPosition).toEqual({ tileX: 30, tileY: 40 });
+    expect(trace.phaseReached).toBe(RunPhase.Resolution);
+    expect(trace.crisisResolved).toBe(true);
+    expect(trace.discoveryCount).toBe(3);
+    expect(trace.keyElements).toEqual(['Na', 'O']);
+    expect(trace.duration).toBe(120000);
+    expect(trace.worldSeed).toBe(42);
+  });
+
+  it('should limit key elements to 5', () => {
+    const run = makeCompletedRun();
+    for (const sym of ['H', 'C', 'Fe', 'Cu', 'Zn', 'Au', 'Hg']) {
+      recordDiscovery(run, 'element', sym);
+    }
+    const trace = createRunTrace(run, meta.greatCycle);
+    expect(trace.keyElements.length).toBeLessThanOrEqual(5);
+  });
+
+  it('should handle null death position (boss victory)', () => {
+    const run = makeCompletedRun({ deathPosition: null });
+    const trace = createRunTrace(run, meta.greatCycle);
+    expect(trace.deathPosition).toBeNull();
+  });
+});
+
+// ─── Cycle Advancement ───────────────────────────────────────────
+
+describe('Cycle Advancement', () => {
+  let meta: MetaState;
+
+  beforeEach(() => {
+    meta = createMetaState();
+  });
+
+  function runAndRecord(runId: number, biome: string = 'catalytic-wastes'): boolean {
+    const run = createRunState(runId, 'alchemist', biome, runId * 100);
+    run.phase = RunPhase.Resolution;
+    run.elapsed = 60000;
+    run.deathPosition = { tileX: 10, tileY: 20 };
+    recordDiscovery(run, 'element', 'Na');
+    return applyRunResults(meta, run);
+  }
+
+  it('should advance runInCycle after each run', () => {
+    expect(meta.greatCycle.runInCycle).toBe(1);
+    runAndRecord(1);
+    expect(meta.greatCycle.runInCycle).toBe(2);
+    runAndRecord(2);
+    expect(meta.greatCycle.runInCycle).toBe(3);
+  });
+
+  it('should stay in cycle 1 for first 6 runs', () => {
+    for (let i = 1; i <= 6; i++) {
+      runAndRecord(i);
+      expect(meta.greatCycle.cycleNumber).toBe(1);
+      expect(meta.greatCycle.theme).toBe('awakening');
+    }
+  });
+
+  it('should trigger Great Renewal on 7th run', () => {
+    for (let i = 1; i <= 6; i++) {
+      const isRenewal = runAndRecord(i);
+      expect(isRenewal).toBe(false);
+    }
+    const isRenewal = runAndRecord(7);
+    expect(isRenewal).toBe(true);
+  });
+
+  it('after renewal should advance to cycle 2', () => {
+    for (let i = 1; i <= 7; i++) runAndRecord(i);
+    expect(meta.greatCycle.cycleNumber).toBe(2);
+    expect(meta.greatCycle.runInCycle).toBe(1);
+    expect(meta.greatCycle.theme).toBe('doubt');
+  });
+
+  it('should accumulate traces within a cycle', () => {
+    runAndRecord(1);
+    runAndRecord(2);
+    runAndRecord(3);
+    expect(meta.greatCycle.currentCycleTraces.length).toBe(3);
+  });
+
+  it('should move current traces to previous on renewal', () => {
+    for (let i = 1; i <= 7; i++) runAndRecord(i);
+    // After renewal: previous has 7 traces, current is empty
+    expect(meta.greatCycle.previousCycleTraces.length).toBe(7);
+    expect(meta.greatCycle.currentCycleTraces.length).toBe(0);
+  });
+
+  it('should track renewals completed', () => {
+    expect(meta.greatCycle.renewalsCompleted).toBe(0);
+    for (let i = 1; i <= 7; i++) runAndRecord(i);
+    expect(meta.greatCycle.renewalsCompleted).toBe(1);
+    for (let i = 8; i <= 14; i++) runAndRecord(i);
+    expect(meta.greatCycle.renewalsCompleted).toBe(2);
+  });
+
+  it('should increment mycelium maturation on renewal', () => {
+    expect(meta.greatCycle.myceliumMaturation).toBe(0);
+    for (let i = 1; i <= 7; i++) runAndRecord(i);
+    expect(meta.greatCycle.myceliumMaturation).toBeGreaterThan(0);
+    expect(meta.greatCycle.myceliumMaturation).toBeLessThanOrEqual(1.0);
+  });
+
+  it('mycelium maturation caps at 1.0', () => {
+    // Simulate many cycles
+    for (let cycle = 0; cycle < 20; cycle++) {
+      for (let run = 1; run <= 7; run++) {
+        runAndRecord(cycle * 7 + run);
+      }
+    }
+    expect(meta.greatCycle.myceliumMaturation).toBeLessThanOrEqual(1.0);
+  });
+});
+
+// ─── Mycelium Strengthening on Renewal ───────────────────────────
+
+describe('Mycelium Strengthening on Renewal', () => {
+  it('should strengthen all Mycelium nodes during renewal', () => {
+    const meta = createMetaState();
+    // Seed some mycelium nodes
+    meta.mycelium.nodes = [
+      { id: 'element:Na', type: 'element', knowledgeId: 'Na', depositedOnRun: 1, strength: 0.3 },
+      { id: 'element:O', type: 'element', knowledgeId: 'O', depositedOnRun: 1, strength: 0.5 },
+    ];
+
+    const oldStrengths = meta.mycelium.nodes.map(n => n.strength);
+    performGreatRenewal(meta);
+
+    for (let i = 0; i < meta.mycelium.nodes.length; i++) {
+      expect(meta.mycelium.nodes[i].strength).toBeGreaterThan(oldStrengths[i]);
+    }
+  });
+
+  it('strength should not exceed 1.0', () => {
+    const meta = createMetaState();
+    meta.mycelium.nodes = [
+      { id: 'element:Na', type: 'element', knowledgeId: 'Na', depositedOnRun: 1, strength: 0.95 },
+    ];
+    performGreatRenewal(meta);
+    expect(meta.mycelium.nodes[0].strength).toBeLessThanOrEqual(1.0);
+  });
+});
+
+// ─── World Modifiers ─────────────────────────────────────────────
+
+describe('Cycle World Modifiers', () => {
+  it('cycle 1 should have baseline modifiers (~1.0)', () => {
+    const mods = getCycleWorldModifiers(1);
+    expect(mods.elevationScaleMultiplier).toBeCloseTo(1.0, 1);
+    expect(mods.detailScaleMultiplier).toBeCloseTo(1.0, 1);
+    expect(mods.resourceDensityMultiplier).toBeCloseTo(1.0, 1);
+    expect(mods.creatureSpawnMultiplier).toBeCloseTo(1.0, 1);
+    expect(mods.escalationRateMultiplier).toBeCloseTo(1.0, 1);
+  });
+
+  it('higher cycles should have higher modifiers', () => {
+    const mod1 = getCycleWorldModifiers(1);
+    const mod3 = getCycleWorldModifiers(3);
+    const mod6 = getCycleWorldModifiers(6);
+
+    expect(mod3.elevationScaleMultiplier).toBeGreaterThan(mod1.elevationScaleMultiplier);
+    expect(mod6.escalationRateMultiplier).toBeGreaterThan(mod3.escalationRateMultiplier);
+    expect(mod6.creatureSpawnMultiplier).toBeGreaterThan(mod1.creatureSpawnMultiplier);
+  });
+
+  it('modifiers should cap at cycle 6', () => {
+    const mod6 = getCycleWorldModifiers(6);
+    const mod10 = getCycleWorldModifiers(10);
+
+    expect(mod10.elevationScaleMultiplier).toBeCloseTo(mod6.elevationScaleMultiplier, 2);
+  });
+});
+
+// ─── Trace Queries ───────────────────────────────────────────────
+
+describe('Trace Queries', () => {
+  let cycle: GreatCycleState;
+
+  beforeEach(() => {
+    cycle = createGreatCycleState();
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', { tileX: 10, tileY: 20 }),
+      makeTrace(2, 'kinetic-mountains', { tileX: 30, tileY: 40 }),
+      makeTrace(3, 'catalytic-wastes', null),
+    ];
+    cycle.previousCycleTraces = [
+      makeTrace(4, 'catalytic-wastes', { tileX: 50, tileY: 60 }),
+    ];
+  });
+
+  function makeTrace(
+    runId: number,
+    biomeId: string,
+    deathPos: { tileX: number; tileY: number } | null,
+  ): RunTrace {
+    return {
+      runId,
+      runInCycle: runId,
+      schoolId: 'alchemist',
+      biomeId,
+      deathPosition: deathPos,
+      phaseReached: RunPhase.Resolution,
+      crisisResolved: false,
+      discoveryCount: 5,
+      keyElements: ['Na'],
+      duration: 60000,
+      worldSeed: runId * 100,
+    };
+  }
+
+  it('should filter traces by biome (current + previous)', () => {
+    const wastesTraces = getTracesForBiome(cycle, 'catalytic-wastes');
+    expect(wastesTraces.length).toBe(3); // 2 current + 1 previous
+  });
+
+  it('should return empty for biome with no traces', () => {
+    const forestTraces = getTracesForBiome(cycle, 'verdant-forests');
+    expect(forestTraces.length).toBe(0);
+  });
+
+  it('should filter death traces (non-null death position)', () => {
+    const allTraces = getTracesForBiome(cycle, 'catalytic-wastes');
+    const deathTraces = getDeathTraces(allTraces);
+    expect(deathTraces.length).toBe(2); // run 1 and run 4 have death positions
+  });
+
+  it('isLastRunInCycle should detect 7th run', () => {
+    cycle.runInCycle = 6;
+    expect(isLastRunInCycle(cycle)).toBe(false);
+    cycle.runInCycle = 7;
+    expect(isLastRunInCycle(cycle)).toBe(true);
+  });
+});
+
+// ─── Cycle Summary ───────────────────────────────────────────────
+
+describe('Cycle Summary', () => {
+  it('should return formatted summary', () => {
+    const cycle = createGreatCycleState();
+    cycle.runInCycle = 3;
+    const summary = getCycleSummary(cycle);
+    expect(summary.cycleNumber).toBe(1);
+    expect(summary.runInCycle).toBe(3);
+    expect(summary.totalRuns).toBe(7);
+    expect(summary.theme).toBe('awakening');
+    expect(summary.isLastRun).toBe(false);
+  });
+
+  it('should indicate last run', () => {
+    const cycle = createGreatCycleState();
+    cycle.runInCycle = 7;
+    const summary = getCycleSummary(cycle);
+    expect(summary.isLastRun).toBe(true);
+  });
+});
+
+// ─── Cycle Narrative Data ────────────────────────────────────────
+
+describe('Cycle Narrative Data', () => {
+  it('should have narrative for all 6 themes', () => {
+    const themes = narrativeData.themes;
+    expect(Object.keys(themes).length).toBe(6);
+    expect(themes.awakening).toBeDefined();
+    expect(themes.doubt).toBeDefined();
+    expect(themes.realization).toBeDefined();
+    expect(themes.attempt).toBeDefined();
+    expect(themes.acceptance).toBeDefined();
+    expect(themes.synthesis).toBeDefined();
+  });
+
+  it('each theme should have Russian text', () => {
+    for (const [, theme] of Object.entries(narrativeData.themes)) {
+      expect(theme.nameRu).toBeDefined();
+      expect(theme.nameRu.length).toBeGreaterThan(0);
+      expect(theme.descriptionRu).toBeDefined();
+      expect(theme.cradleQuoteRu).toBeDefined();
+      expect(theme.loreFrag.length).toBeGreaterThan(0);
+      for (const frag of theme.loreFrag) {
+        expect(frag.textRu).toBeDefined();
+        expect(frag.textRu.length).toBeGreaterThan(0);
+      }
+    }
+  });
+
+  it('should have renewal messages', () => {
+    expect(narrativeData.renewalMessages.length).toBeGreaterThan(0);
+    for (const msg of narrativeData.renewalMessages) {
+      expect(msg.textRu).toBeDefined();
+    }
+  });
+
+  it('should have trace messages for death and discovery sites', () => {
+    expect(narrativeData.traceMessages.death_site.length).toBeGreaterThan(0);
+    expect(narrativeData.traceMessages.discovery_site.length).toBeGreaterThan(0);
+  });
+});
+
+// ─── Full Integration: 2 Complete Cycles ─────────────────────────
+
+describe('Full Integration: 2 Complete Cycles', () => {
+  it('should progress through 2 cycles correctly', () => {
+    const meta = createMetaState();
+    let renewalCount = 0;
+
+    for (let i = 1; i <= 14; i++) {
+      const run = createRunState(i, 'alchemist', 'catalytic-wastes', i * 100);
+      run.phase = RunPhase.Crisis;
+      run.elapsed = 90000;
+      run.deathPosition = { tileX: i * 5, tileY: i * 3 };
+      recordDiscovery(run, 'element', `E${i}`);
+
+      const isRenewal = applyRunResults(meta, run);
+      if (isRenewal) renewalCount++;
+    }
+
+    expect(renewalCount).toBe(2);
+    expect(meta.greatCycle.cycleNumber).toBe(3);
+    expect(meta.greatCycle.theme).toBe('realization');
+    expect(meta.greatCycle.runInCycle).toBe(1);
+    expect(meta.greatCycle.renewalsCompleted).toBe(2);
+    expect(meta.greatCycle.previousCycleTraces.length).toBe(7);
+    expect(meta.greatCycle.currentCycleTraces.length).toBe(0);
+    expect(meta.totalRuns).toBe(14);
+  });
+});
+
+// ─── RunState Extended Fields ────────────────────────────────────
+
+describe('RunState Extended Fields', () => {
+  it('should include biomeId and worldSeed', () => {
+    const run = createRunState(1, 'alchemist', 'kinetic-mountains', 12345);
+    expect(run.biomeId).toBe('kinetic-mountains');
+    expect(run.worldSeed).toBe(12345);
+    expect(run.deathPosition).toBeNull();
+  });
+
+  it('should default biomeId to catalytic-wastes', () => {
+    const run = createRunState(1, 'alchemist');
+    expect(run.biomeId).toBe('catalytic-wastes');
+  });
+
+  it('RunSummary should include biomeId and cycleNumber', () => {
+    const meta = createMetaState();
+    const run = createRunState(1, 'alchemist', 'verdant-forests', 999);
+    run.phase = RunPhase.Exploration;
+    run.elapsed = 30000;
+    recordDiscovery(run, 'element', 'H');
+    applyRunResults(meta, run);
+
+    const lastSummary = meta.runHistory[meta.runHistory.length - 1];
+    expect(lastSummary.biomeId).toBe('verdant-forests');
+    expect(lastSummary.cycleNumber).toBe(1);
+  });
+});

tests/interaction.test.ts

@@ -0,0 +1,191 @@
+/**
+ * Resource Interaction Tests — Phase 4.3
+ *
+ * Tests: resource element picking, proximity detection,
+ * collection into inventory, resource depletion.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { createWorld, addEntity, addComponent, query } from 'bitecs';
+import { Position, Resource, PlayerTag } from '../src/ecs/components';
+import { Inventory } from '../src/player/inventory';
+import {
+  pickResourceElement,
+  interactionSystem,
+  type ResourceInfo,
+  type InteractionResult,
+  MINERAL_ELEMENTS,
+  GEYSER_ELEMENTS,
+} from '../src/player/interaction';
+
+// === Helpers ===
+
+function createTestWorld() {
+  const world = createWorld();
+  const resourceData = new Map<number, ResourceInfo>();
+  const inventory = new Inventory();
+  return { world, resourceData, inventory };
+}
+
+function addPlayer(world: ReturnType<typeof createWorld>, x: number, y: number): number {
+  const eid = addEntity(world);
+  addComponent(world, eid, Position);
+  addComponent(world, eid, PlayerTag);
+  Position.x[eid] = x;
+  Position.y[eid] = y;
+  return eid;
+}
+
+function addResource(
+  world: ReturnType<typeof createWorld>,
+  resourceData: Map<number, ResourceInfo>,
+  x: number,
+  y: number,
+  itemId: string,
+  quantity: number,
+  range = 40,
+): number {
+  const eid = addEntity(world);
+  addComponent(world, eid, Position);
+  addComponent(world, eid, Resource);
+  Position.x[eid] = x;
+  Position.y[eid] = y;
+  Resource.quantity[eid] = quantity;
+  Resource.interactRange[eid] = range;
+  resourceData.set(eid, { itemId, tileX: Math.floor(x / 32), tileY: Math.floor(y / 32) });
+  return eid;
+}
+
+// === pickResourceElement ===
+
+describe('pickResourceElement', () => {
+  it('always returns element from provided list', () => {
+    for (let x = 0; x < 20; x++) {
+      for (let y = 0; y < 20; y++) {
+        const el = pickResourceElement(x, y, 12345, MINERAL_ELEMENTS);
+        expect(MINERAL_ELEMENTS).toContain(el);
+      }
+    }
+  });
+
+  it('is deterministic (same inputs → same output)', () => {
+    const a = pickResourceElement(5, 10, 42, MINERAL_ELEMENTS);
+    const b = pickResourceElement(5, 10, 42, MINERAL_ELEMENTS);
+    expect(a).toBe(b);
+  });
+
+  it('varies with different positions', () => {
+    const results = new Set<string>();
+    for (let i = 0; i < 100; i++) {
+      results.add(pickResourceElement(i, i * 7, 42, MINERAL_ELEMENTS));
+    }
+    // Should use more than one element (statistical certainty)
+    expect(results.size).toBeGreaterThan(1);
+  });
+
+  it('works with geyser elements', () => {
+    const el = pickResourceElement(3, 7, 42, GEYSER_ELEMENTS);
+    expect(GEYSER_ELEMENTS).toContain(el);
+  });
+});
+
+// === Interaction System ===
+
+describe('interactionSystem — collection', () => {
+  it('collects element when in range and pressing E', () => {
+    const { world, resourceData, inventory } = createTestWorld();
+    addPlayer(world, 100, 100);
+    addResource(world, resourceData, 120, 100, 'Fe', 5);
+
+    const result = interactionSystem(world, true, inventory, resourceData);
+
+    expect(result).not.toBeNull();
+    expect(result!.type).toBe('collected');
+    expect(result!.itemId).toBe('Fe');
+    expect(inventory.getCount('Fe')).toBe(1);
+  });
+
+  it('does nothing when E is not pressed', () => {
+    const { world, resourceData, inventory } = createTestWorld();
+    addPlayer(world, 100, 100);
+    addResource(world, resourceData, 120, 100, 'Fe', 5);
+
+    const result = interactionSystem(world, false, inventory, resourceData);
+
+    expect(result).toBeNull();
+    expect(inventory.getCount('Fe')).toBe(0);
+  });
+
+  it('does nothing when no resources in range', () => {
+    const { world, resourceData, inventory } = createTestWorld();
+    addPlayer(world, 100, 100);
+    addResource(world, resourceData, 500, 500, 'Fe', 5); // far away
+
+    const result = interactionSystem(world, true, inventory, resourceData);
+
+    expect(result).not.toBeNull();
+    expect(result!.type).toBe('nothing_nearby');
+  });
+
+  it('picks closest resource when multiple in range', () => {
+    const { world, resourceData, inventory } = createTestWorld();
+    addPlayer(world, 100, 100);
+    addResource(world, resourceData, 130, 100, 'Cu', 3); // 30px away
+    addResource(world, resourceData, 115, 100, 'Fe', 5); // 15px away (closer)
+
+    const result = interactionSystem(world, true, inventory, resourceData);
+
+    expect(result!.itemId).toBe('Fe'); // picked closer one
+  });
+
+  it('decrements resource quantity on collection', () => {
+    const { world, resourceData, inventory } = createTestWorld();
+    addPlayer(world, 100, 100);
+    const resEid = addResource(world, resourceData, 120, 100, 'Fe', 3);
+
+    interactionSystem(world, true, inventory, resourceData);
+
+    expect(Resource.quantity[resEid]).toBe(2);
+  });
+});
+
+describe('interactionSystem — depletion', () => {
+  it('depletes resource when quantity reaches 0', () => {
+    const { world, resourceData, inventory } = createTestWorld();
+    addPlayer(world, 100, 100);
+    addResource(world, resourceData, 120, 100, 'Fe', 1);
+
+    const result = interactionSystem(world, true, inventory, resourceData);
+
+    expect(result!.type).toBe('depleted');
+    expect(result!.itemId).toBe('Fe');
+    expect(resourceData.size).toBe(0);
+  });
+
+  it('removes entity from world on depletion', () => {
+    const { world, resourceData, inventory } = createTestWorld();
+    addPlayer(world, 100, 100);
+    addResource(world, resourceData, 120, 100, 'Fe', 1);
+
+    interactionSystem(world, true, inventory, resourceData);
+
+    const remaining = query(world, [Resource]);
+    expect(remaining.length).toBe(0);
+  });
+});
+
+describe('interactionSystem — inventory full', () => {
+  it('reports inventory_full when cannot add', () => {
+    const { world, resourceData } = createTestWorld();
+    const inventory = new Inventory(1, 1); // very small
+    inventory.addItem('H', 1); // fills it up
+
+    addPlayer(world, 100, 100);
+    addResource(world, resourceData, 120, 100, 'Fe', 5);
+
+    const result = interactionSystem(world, true, inventory, resourceData);
+
+    expect(result!.type).toBe('inventory_full');
+    expect(Resource.quantity[query(world, [Resource])[0]]).toBe(5); // not consumed
+  });
+});

tests/inventory.test.ts

@@ -0,0 +1,244 @@
+/**
+ * Inventory System Tests — Phase 4.2
+ *
+ * Weight-based inventory with element stacking,
+ * mass limits, and slot limits.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { Inventory, getItemMass } from '../src/player/inventory';
+
+// === Item Mass Lookup ===
+
+describe('getItemMass', () => {
+  it('returns atomic mass for elements', () => {
+    expect(getItemMass('H')).toBeCloseTo(1.008);
+    expect(getItemMass('Na')).toBeCloseTo(22.99);
+    expect(getItemMass('Fe')).toBeCloseTo(55.845);
+    expect(getItemMass('O')).toBeCloseTo(15.999);
+  });
+
+  it('returns molecular mass for compounds', () => {
+    expect(getItemMass('NaCl')).toBeCloseTo(58.44);
+    expect(getItemMass('H2O')).toBeCloseTo(18.015);
+    expect(getItemMass('CO2')).toBeCloseTo(44.01);
+  });
+
+  it('returns 0 for unknown items', () => {
+    expect(getItemMass('UNKNOWN')).toBe(0);
+    expect(getItemMass('')).toBe(0);
+  });
+});
+
+// === Inventory Core ===
+
+describe('Inventory — creation', () => {
+  it('starts empty', () => {
+    const inv = new Inventory();
+    expect(inv.isEmpty()).toBe(true);
+    expect(inv.getItems()).toEqual([]);
+    expect(inv.getTotalWeight()).toBe(0);
+    expect(inv.slotCount).toBe(0);
+  });
+
+  it('respects custom limits', () => {
+    const inv = new Inventory(100, 5);
+    expect(inv.maxWeight).toBe(100);
+    expect(inv.maxSlots).toBe(5);
+  });
+});
+
+describe('Inventory — adding items', () => {
+  it('adds elements', () => {
+    const inv = new Inventory();
+    const added = inv.addItem('H', 3);
+    expect(added).toBe(3);
+    expect(inv.getCount('H')).toBe(3);
+    expect(inv.isEmpty()).toBe(false);
+    expect(inv.slotCount).toBe(1);
+  });
+
+  it('adds compounds', () => {
+    const inv = new Inventory();
+    const added = inv.addItem('NaCl', 1);
+    expect(added).toBe(1);
+    expect(inv.getCount('NaCl')).toBe(1);
+  });
+
+  it('stacks same elements', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 2);
+    inv.addItem('Na', 3);
+    expect(inv.getCount('Na')).toBe(5);
+    expect(inv.slotCount).toBe(1);
+  });
+
+  it('stacking does not consume new slot', () => {
+    const inv = new Inventory(10000, 3);
+    inv.addItem('H', 1);
+    inv.addItem('O', 1);
+    inv.addItem('Na', 1);
+    const added = inv.addItem('H', 5);
+    expect(added).toBe(5);
+    expect(inv.getCount('H')).toBe(6);
+    expect(inv.slotCount).toBe(3);
+  });
+
+  it('returns 0 for unknown items', () => {
+    const inv = new Inventory();
+    expect(inv.addItem('UNKNOWN', 1)).toBe(0);
+    expect(inv.isEmpty()).toBe(true);
+  });
+
+  it('returns 0 for zero/negative count', () => {
+    const inv = new Inventory();
+    expect(inv.addItem('H', 0)).toBe(0);
+    expect(inv.addItem('H', -1)).toBe(0);
+  });
+});
+
+describe('Inventory — removing items', () => {
+  it('removes items', () => {
+    const inv = new Inventory();
+    inv.addItem('H', 5);
+    const removed = inv.removeItem('H', 3);
+    expect(removed).toBe(3);
+    expect(inv.getCount('H')).toBe(2);
+  });
+
+  it('cleans up slot when count reaches zero', () => {
+    const inv = new Inventory();
+    inv.addItem('H', 3);
+    inv.removeItem('H', 3);
+    expect(inv.getCount('H')).toBe(0);
+    expect(inv.slotCount).toBe(0);
+    expect(inv.isEmpty()).toBe(true);
+  });
+
+  it('removes only what is available', () => {
+    const inv = new Inventory();
+    inv.addItem('H', 2);
+    const removed = inv.removeItem('H', 5);
+    expect(removed).toBe(2);
+    expect(inv.getCount('H')).toBe(0);
+  });
+
+  it('returns 0 for non-existent item', () => {
+    const inv = new Inventory();
+    expect(inv.removeItem('H', 1)).toBe(0);
+  });
+
+  it('returns 0 for zero/negative count', () => {
+    const inv = new Inventory();
+    inv.addItem('H', 5);
+    expect(inv.removeItem('H', 0)).toBe(0);
+    expect(inv.removeItem('H', -1)).toBe(0);
+  });
+});
+
+describe('Inventory — weight system', () => {
+  it('calculates total weight from atomic masses', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 2); // 22.99 * 2 = 45.98
+    expect(inv.getTotalWeight()).toBeCloseTo(22.99 * 2);
+  });
+
+  it('calculates mixed element + compound weight', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 1); // 22.99
+    inv.addItem('NaCl', 1); // 58.44
+    expect(inv.getTotalWeight()).toBeCloseTo(22.99 + 58.44);
+  });
+
+  it('limits additions by weight', () => {
+    const inv = new Inventory(100); // 100 AMU limit
+    // Na mass = 22.99 → max 4 fit (4 * 22.99 = 91.96)
+    const added = inv.addItem('Na', 10);
+    expect(added).toBe(4);
+    expect(inv.getCount('Na')).toBe(4);
+    expect(inv.getTotalWeight()).toBeCloseTo(22.99 * 4);
+  });
+
+  it('weight frees up after removal', () => {
+    const inv = new Inventory(100);
+    inv.addItem('Na', 4); // 91.96
+    inv.removeItem('Na', 2); // now 45.98 used, ~54 free
+    const added = inv.addItem('Na', 3); // 2 more fit (45.98 + 2*22.99 = 91.96)
+    expect(added).toBe(2);
+    expect(inv.getCount('Na')).toBe(4);
+  });
+
+  it('getItemWeight returns stack weight', () => {
+    const inv = new Inventory();
+    inv.addItem('Na', 3);
+    expect(inv.getItemWeight('Na')).toBeCloseTo(22.99 * 3);
+  });
+
+  it('getItemWeight returns 0 for absent item', () => {
+    const inv = new Inventory();
+    expect(inv.getItemWeight('H')).toBe(0);
+  });
+});
+
+describe('Inventory — slot limits', () => {
+  it('respects max slots', () => {
+    const inv = new Inventory(10000, 3);
+    inv.addItem('H', 1);
+    inv.addItem('O', 1);
+    inv.addItem('Na', 1);
+    const added = inv.addItem('Fe', 1); // 4th slot
+    expect(added).toBe(0);
+    expect(inv.slotCount).toBe(3);
+    expect(inv.hasItem('Fe')).toBe(false);
+  });
+
+  it('frees slot after full removal', () => {
+    const inv = new Inventory(10000, 2);
+    inv.addItem('H', 1);
+    inv.addItem('O', 1);
+    expect(inv.addItem('Na', 1)).toBe(0); // full
+    inv.removeItem('O', 1); // free a slot
+    expect(inv.addItem('Na', 1)).toBe(1); // now fits
+    expect(inv.slotCount).toBe(2);
+  });
+});
+
+describe('Inventory — queries', () => {
+  it('hasItem checks against count', () => {
+    const inv = new Inventory();
+    inv.addItem('H', 3);
+    expect(inv.hasItem('H', 1)).toBe(true);
+    expect(inv.hasItem('H', 3)).toBe(true);
+    expect(inv.hasItem('H', 4)).toBe(false);
+    expect(inv.hasItem('O')).toBe(false);
+  });
+
+  it('getItems returns all items', () => {
+    const inv = new Inventory();
+    inv.addItem('H', 3);
+    inv.addItem('Na', 2);
+    const items = inv.getItems();
+    expect(items).toHaveLength(2);
+    expect(items).toContainEqual({ id: 'H', count: 3 });
+    expect(items).toContainEqual({ id: 'Na', count: 2 });
+  });
+
+  it('getCount returns 0 for absent item', () => {
+    const inv = new Inventory();
+    expect(inv.getCount('H')).toBe(0);
+  });
+});
+
+describe('Inventory — clear', () => {
+  it('removes everything', () => {
+    const inv = new Inventory();
+    inv.addItem('H', 3);
+    inv.addItem('Na', 2);
+    inv.addItem('NaCl', 1);
+    inv.clear();
+    expect(inv.isEmpty()).toBe(true);
+    expect(inv.getTotalWeight()).toBe(0);
+    expect(inv.slotCount).toBe(0);
+    expect(inv.getItems()).toEqual([]);
+  });
+});

tests/mycelium.test.ts

@@ -0,0 +1,537 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import type { MyceliumGraphData, MetaState, RunState } from '../src/run/types';
+import { RunPhase } from '../src/run/types';
+import { createMetaState } from '../src/run/meta';
+import {
+  createMyceliumGraph,
+  depositKnowledge,
+  getNode,
+  getEdge,
+  getNodesByType,
+  getConnectedNodes,
+  getGraphStats,
+} from '../src/mycelium/graph';
+import {
+  extractMemoryFlashes,
+  generateFlashText,
+} from '../src/mycelium/knowledge';
+import {
+  createMycosisState,
+  updateMycosis,
+  getMycosisVisuals,
+} from '../src/mycelium/mycosis';
+import {
+  getAvailableBonuses,
+  purchaseBonus,
+  canAffordBonus,
+} from '../src/mycelium/shop';
+import {
+  spawnFungalNodes,
+} from '../src/mycelium/nodes';
+import type { MycosisState, MemoryFlash, FungalNodeInfo } from '../src/mycelium/types';
+import { MYCOSIS_CONFIG } from '../src/mycelium/types';
+
+// ─── Test helpers ────────────────────────────────────────────────
+
+function createTestRunState(runId: number = 1): RunState {
+  return {
+    runId,
+    schoolId: 'alchemist',
+    phase: RunPhase.Exploration,
+    phaseTimer: 0,
+    elapsed: 60000,
+    escalation: 0,
+    crisisActive: false,
+    crisisResolved: false,
+    discoveries: {
+      elements: new Set(['Na', 'Cl', 'H', 'O']),
+      reactions: new Set(['Na+Cl']),
+      compounds: new Set(['NaCl']),
+      creatures: new Set(['crystallid']),
+    },
+    alive: true,
+  };
+}
+
+function createTestMeta(): MetaState {
+  const meta = createMetaState();
+  meta.totalRuns = 2;
+  meta.spores = 100;
+  meta.mycelium = createMyceliumGraph();
+  return meta;
+}
+
+// ─── Mycelium Graph Tests ────────────────────────────────────────
+
+describe('Mycelium Graph', () => {
+  let graph: MyceliumGraphData;
+
+  beforeEach(() => {
+    graph = createMyceliumGraph();
+  });
+
+  it('should create an empty graph', () => {
+    expect(graph.nodes).toHaveLength(0);
+    expect(graph.edges).toHaveLength(0);
+    expect(graph.totalDeposits).toBe(0);
+    expect(graph.totalExtractions).toBe(0);
+  });
+
+  it('should deposit element knowledge from a run', () => {
+    const run = createTestRunState(1);
+    const result = depositKnowledge(graph, run);
+
+    expect(result.newNodes).toBeGreaterThan(0);
+    // Should have nodes for elements + reactions + compounds + creatures
+    expect(graph.nodes.length).toBeGreaterThanOrEqual(4);
+    expect(graph.totalDeposits).toBe(1);
+  });
+
+  it('should create nodes for all discovery types', () => {
+    const run = createTestRunState(1);
+    depositKnowledge(graph, run);
+
+    // 4 elements (Na, Cl, H, O) + 1 reaction + 1 compound + 1 creature = 7
+    expect(graph.nodes).toHaveLength(7);
+
+    const elementNodes = getNodesByType(graph, 'element');
+    expect(elementNodes).toHaveLength(4);
+
+    const reactionNodes = getNodesByType(graph, 'reaction');
+    expect(reactionNodes).toHaveLength(1);
+
+    const compoundNodes = getNodesByType(graph, 'compound');
+    expect(compoundNodes).toHaveLength(1);
+
+    const creatureNodes = getNodesByType(graph, 'creature');
+    expect(creatureNodes).toHaveLength(1);
+  });
+
+  it('should create edges between related discoveries', () => {
+    const run = createTestRunState(1);
+    depositKnowledge(graph, run);
+
+    // Elements that form a reaction should be connected to the reaction
+    // Na + Cl → NaCl: edges Na→reaction, Cl→reaction, reaction→compound
+    expect(graph.edges.length).toBeGreaterThan(0);
+  });
+
+  it('should strengthen existing nodes on re-deposit', () => {
+    const run1 = createTestRunState(1);
+    depositKnowledge(graph, run1);
+
+    const naNode = getNode(graph, 'element:Na');
+    expect(naNode).toBeDefined();
+    const initialStrength = naNode!.strength;
+
+    // Second deposit with same discoveries should strengthen
+    const run2 = createTestRunState(2);
+    run2.discoveries.elements = new Set(['Na']); // Only Na
+    run2.discoveries.reactions = new Set();
+    run2.discoveries.compounds = new Set();
+    run2.discoveries.creatures = new Set();
+    const result = depositKnowledge(graph, run2);
+
+    expect(result.strengthened).toBe(1);
+    expect(result.newNodes).toBe(0);
+
+    const naNodeAfter = getNode(graph, 'element:Na');
+    expect(naNodeAfter!.strength).toBeGreaterThan(initialStrength);
+  });
+
+  it('should cap node strength at 1.0', () => {
+    const run = createTestRunState(1);
+    run.discoveries.elements = new Set(['Na']);
+    run.discoveries.reactions = new Set();
+    run.discoveries.compounds = new Set();
+    run.discoveries.creatures = new Set();
+
+    // Deposit many times
+    for (let i = 0; i < 20; i++) {
+      depositKnowledge(graph, run);
+    }
+
+    const naNode = getNode(graph, 'element:Na');
+    expect(naNode!.strength).toBeLessThanOrEqual(1.0);
+  });
+
+  it('should look up nodes by ID', () => {
+    const run = createTestRunState(1);
+    depositKnowledge(graph, run);
+
+    const node = getNode(graph, 'element:Na');
+    expect(node).toBeDefined();
+    expect(node!.type).toBe('element');
+    expect(node!.knowledgeId).toBe('Na');
+
+    const missing = getNode(graph, 'element:Au');
+    expect(missing).toBeUndefined();
+  });
+
+  it('should look up edges between nodes', () => {
+    const run = createTestRunState(1);
+    depositKnowledge(graph, run);
+
+    // There should be edges from Na and Cl to the Na+Cl reaction
+    const naEdge = getEdge(graph, 'element:Na', 'reaction:Na+Cl');
+    // Edge may exist in either direction — check both
+    const naEdgeReverse = getEdge(graph, 'reaction:Na+Cl', 'element:Na');
+    expect(naEdge ?? naEdgeReverse).toBeDefined();
+  });
+
+  it('should return connected nodes', () => {
+    const run = createTestRunState(1);
+    depositKnowledge(graph, run);
+
+    // Na should be connected to the Na+Cl reaction
+    const connected = getConnectedNodes(graph, 'element:Na');
+    expect(connected.length).toBeGreaterThan(0);
+  });
+
+  it('should report graph statistics', () => {
+    const run = createTestRunState(1);
+    depositKnowledge(graph, run);
+
+    const stats = getGraphStats(graph);
+    expect(stats.nodeCount).toBe(7);
+    expect(stats.edgeCount).toBeGreaterThan(0);
+    expect(stats.totalDeposits).toBe(1);
+    expect(stats.averageStrength).toBeGreaterThan(0);
+    expect(stats.averageStrength).toBeLessThanOrEqual(1);
+  });
+});
+
+// ─── Knowledge System Tests ──────────────────────────────────────
+
+describe('Knowledge System', () => {
+  let graph: MyceliumGraphData;
+
+  beforeEach(() => {
+    graph = createMyceliumGraph();
+    const run = createTestRunState(1);
+    depositKnowledge(graph, run);
+  });
+
+  it('should extract memory flashes from populated graph', () => {
+    const flashes = extractMemoryFlashes(graph, 3);
+    expect(flashes.length).toBeGreaterThan(0);
+    expect(flashes.length).toBeLessThanOrEqual(3);
+  });
+
+  it('should return empty flashes from empty graph', () => {
+    const emptyGraph = createMyceliumGraph();
+    const flashes = extractMemoryFlashes(emptyGraph, 3);
+    expect(flashes).toHaveLength(0);
+  });
+
+  it('should generate flash text for element hints', () => {
+    const flash = generateFlashText('element', 'Na');
+    expect(flash.type).toBe('element_hint');
+    expect(flash.text.length).toBeGreaterThan(0);
+    expect(flash.textRu.length).toBeGreaterThan(0);
+    // Should contain the element name somewhere
+    expect(flash.text).toContain('Na');
+    expect(flash.textRu).toContain('Na');
+  });
+
+  it('should generate flash text for reaction hints', () => {
+    const flash = generateFlashText('reaction', 'Na+Cl');
+    expect(flash.type).toBe('reaction_hint');
+    expect(flash.text.length).toBeGreaterThan(0);
+  });
+
+  it('should generate flash text for creature hints', () => {
+    const flash = generateFlashText('creature', 'crystallid');
+    expect(flash.type).toBe('creature_hint');
+    expect(flash.text.length).toBeGreaterThan(0);
+  });
+
+  it('should increment extraction counter', () => {
+    expect(graph.totalExtractions).toBe(0);
+    extractMemoryFlashes(graph, 3);
+    expect(graph.totalExtractions).toBe(1);
+  });
+
+  it('should prefer stronger nodes for flashes', () => {
+    // Strengthen Na by depositing multiple times
+    for (let i = 0; i < 5; i++) {
+      const run = createTestRunState(i + 2);
+      run.discoveries.elements = new Set(['Na']);
+      run.discoveries.reactions = new Set();
+      run.discoveries.compounds = new Set();
+      run.discoveries.creatures = new Set();
+      depositKnowledge(graph, run);
+    }
+
+    // Extract many flashes — Na should appear frequently
+    let naCount = 0;
+    for (let i = 0; i < 10; i++) {
+      const flashes = extractMemoryFlashes(graph, 3);
+      for (const f of flashes) {
+        if (f.text.includes('Na') || f.textRu.includes('Na')) naCount++;
+      }
+    }
+    // Na should appear at least once in 10 rounds of 3 flashes
+    expect(naCount).toBeGreaterThan(0);
+  });
+});
+
+// ─── Mycosis Tests ───────────────────────────────────────────────
+
+describe('Mycosis', () => {
+  let state: MycosisState;
+
+  beforeEach(() => {
+    state = createMycosisState();
+  });
+
+  it('should create initial mycosis state at zero', () => {
+    expect(state.level).toBe(0);
+    expect(state.exposure).toBe(0);
+    expect(state.revealing).toBe(false);
+  });
+
+  it('should increase level when near a fungal node', () => {
+    updateMycosis(state, 1000, true); // 1 second near a node
+    expect(state.level).toBeGreaterThan(0);
+    expect(state.exposure).toBe(1000);
+  });
+
+  it('should decrease level when away from nodes', () => {
+    // Build up some mycosis
+    updateMycosis(state, 5000, true);
+    const peakLevel = state.level;
+
+    // Move away
+    updateMycosis(state, 2000, false);
+    expect(state.level).toBeLessThan(peakLevel);
+  });
+
+  it('should not go below zero', () => {
+    updateMycosis(state, 10000, false);
+    expect(state.level).toBe(0);
+  });
+
+  it('should not exceed max level', () => {
+    updateMycosis(state, 100000, true); // Very long exposure
+    expect(state.level).toBeLessThanOrEqual(MYCOSIS_CONFIG.maxLevel);
+  });
+
+  it('should start revealing at threshold', () => {
+    // Build up to reveal threshold
+    const timeToThreshold = MYCOSIS_CONFIG.revealThreshold / MYCOSIS_CONFIG.buildRate * 1000;
+    updateMycosis(state, timeToThreshold + 1000, true);
+    expect(state.revealing).toBe(true);
+  });
+
+  it('should stop revealing when level drops below threshold', () => {
+    // Build up past threshold
+    const timeToThreshold = MYCOSIS_CONFIG.revealThreshold / MYCOSIS_CONFIG.buildRate * 1000;
+    updateMycosis(state, timeToThreshold + 2000, true);
+    expect(state.revealing).toBe(true);
+
+    // Let it decay
+    const decayTime = (state.level - MYCOSIS_CONFIG.revealThreshold + 0.1) / MYCOSIS_CONFIG.decayRate * 1000;
+    updateMycosis(state, decayTime + 1000, false);
+    expect(state.revealing).toBe(false);
+  });
+
+  it('should return visual parameters based on level', () => {
+    updateMycosis(state, 5000, true);
+
+    const visuals = getMycosisVisuals(state);
+    expect(visuals.tintColor).toBe(MYCOSIS_CONFIG.tintColor);
+    expect(visuals.tintAlpha).toBeGreaterThan(0);
+    expect(visuals.tintAlpha).toBeLessThanOrEqual(MYCOSIS_CONFIG.maxTintAlpha);
+    expect(visuals.distortionStrength).toBeGreaterThanOrEqual(0);
+  });
+
+  it('should have zero visuals when mycosis is zero', () => {
+    const visuals = getMycosisVisuals(state);
+    expect(visuals.tintAlpha).toBe(0);
+    expect(visuals.distortionStrength).toBe(0);
+  });
+});
+
+// ─── Spore Shop Tests ────────────────────────────────────────────
+
+describe('Spore Shop', () => {
+  it('should list available bonuses', () => {
+    const bonuses = getAvailableBonuses();
+    expect(bonuses.length).toBeGreaterThan(0);
+
+    // Each bonus should have required fields
+    for (const bonus of bonuses) {
+      expect(bonus.id).toBeTruthy();
+      expect(bonus.nameRu).toBeTruthy();
+      expect(bonus.cost).toBeGreaterThan(0);
+      expect(bonus.effect).toBeDefined();
+    }
+  });
+
+  it('should check affordability correctly', () => {
+    const meta = createTestMeta();
+    meta.spores = 15;
+
+    const bonuses = getAvailableBonuses();
+    const cheapBonus = bonuses.find(b => b.cost <= 15);
+    const expensiveBonus = bonuses.find(b => b.cost > 15);
+
+    if (cheapBonus) {
+      expect(canAffordBonus(meta, cheapBonus.id)).toBe(true);
+    }
+    if (expensiveBonus) {
+      expect(canAffordBonus(meta, expensiveBonus.id)).toBe(false);
+    }
+  });
+
+  it('should deduct spores on purchase', () => {
+    const meta = createTestMeta();
+    const initialSpores = meta.spores;
+
+    const bonuses = getAvailableBonuses();
+    const bonus = bonuses[0];
+    const result = purchaseBonus(meta, bonus.id);
+
+    expect(result).not.toBeNull();
+    expect(meta.spores).toBe(initialSpores - bonus.cost);
+  });
+
+  it('should return the purchased effect', () => {
+    const meta = createTestMeta();
+    const bonuses = getAvailableBonuses();
+    const bonus = bonuses.find(b => b.effect.type === 'extra_health');
+    expect(bonus).toBeDefined();
+
+    const result = purchaseBonus(meta, bonus!.id);
+    expect(result).not.toBeNull();
+    expect(result!.type).toBe('extra_health');
+  });
+
+  it('should fail to purchase with insufficient spores', () => {
+    const meta = createTestMeta();
+    meta.spores = 0;
+
+    const bonuses = getAvailableBonuses();
+    const result = purchaseBonus(meta, bonuses[0].id);
+    expect(result).toBeNull();
+    expect(meta.spores).toBe(0); // unchanged
+  });
+
+  it('should not allow non-repeatable bonuses to be purchased twice', () => {
+    const meta = createTestMeta();
+    meta.spores = 200;
+
+    const bonuses = getAvailableBonuses();
+    const nonRepeatable = bonuses.find(b => !b.repeatable);
+    if (!nonRepeatable) return; // skip if all are repeatable
+
+    const result1 = purchaseBonus(meta, nonRepeatable.id);
+    expect(result1).not.toBeNull();
+
+    const result2 = purchaseBonus(meta, nonRepeatable.id);
+    expect(result2).toBeNull();
+  });
+});
+
+// ─── Fungal Node Spawning Tests ──────────────────────────────────
+
+describe('Fungal Node Spawning', () => {
+  // Build a simple 20x20 grid with walkable ground
+  const biome = {
+    id: 'test',
+    name: 'Test',
+    nameRu: 'Тест',
+    description: '',
+    descriptionRu: '',
+    tileSize: 16,
+    mapWidth: 20,
+    mapHeight: 20,
+    tiles: [
+      { id: 0, name: 'ground', nameRu: 'земля', color: '#555', walkable: true, damage: 0, interactive: false, resource: false },
+      { id: 1, name: 'acid-deep', nameRu: 'кислота', color: '#0f0', walkable: false, damage: 5, interactive: false, resource: false },
+      { id: 2, name: 'scorched-earth', nameRu: 'выжженная', color: '#333', walkable: true, damage: 0, interactive: false, resource: false },
+    ],
+    generation: {
+      elevationScale: 0.1,
+      detailScale: 0.2,
+      elevationRules: [{ below: 0.5, tileId: 0 }],
+      geyserThreshold: 0.9,
+      mineralThreshold: 0.8,
+      geyserOnTile: 0,
+      mineralOnTiles: [0],
+    },
+  };
+
+  function createTestGrid(): number[][] {
+    const grid: number[][] = [];
+    for (let y = 0; y < 20; y++) {
+      const row: number[] = [];
+      for (let x = 0; x < 20; x++) {
+        // Mostly ground, some acid
+        row.push(x === 0 && y === 0 ? 1 : 0);
+      }
+      grid.push(row);
+    }
+    return grid;
+  }
+
+  it('should spawn fungal nodes on walkable tiles', async () => {
+    const { createWorld } = await import('bitecs');
+    const world = createWorld();
+    const grid = createTestGrid();
+
+    const nodeData = spawnFungalNodes(world, grid, biome, 42);
+    expect(nodeData.size).toBeGreaterThan(0);
+  });
+
+  it('should not spawn on non-walkable tiles', async () => {
+    const { createWorld } = await import('bitecs');
+    const world = createWorld();
+
+    // Make grid entirely non-walkable
+    const grid: number[][] = [];
+    for (let y = 0; y < 20; y++) {
+      grid.push(Array(20).fill(1)); // all acid
+    }
+
+    const nodeData = spawnFungalNodes(world, grid, biome, 42);
+    expect(nodeData.size).toBe(0);
+  });
+
+  it('should use deterministic placement based on seed', async () => {
+    const { createWorld } = await import('bitecs');
+    const grid = createTestGrid();
+
+    const world1 = createWorld();
+    const data1 = spawnFungalNodes(world1, grid, biome, 42);
+
+    const world2 = createWorld();
+    const data2 = spawnFungalNodes(world2, grid, biome, 42);
+
+    // Same seed → same positions
+    const positions1 = [...data1.values()].map(d => `${d.tileX},${d.tileY}`).sort();
+    const positions2 = [...data2.values()].map(d => `${d.tileX},${d.tileY}`).sort();
+    expect(positions1).toEqual(positions2);
+  });
+
+  it('should maintain minimum spacing between nodes', async () => {
+    const { createWorld } = await import('bitecs');
+    const world = createWorld();
+    const grid = createTestGrid();
+
+    const nodeData = spawnFungalNodes(world, grid, biome, 42);
+    const positions = [...nodeData.values()].map(d => ({ x: d.tileX, y: d.tileY }));
+
+    // No two nodes should be closer than minSpacing
+    // (on a 20x20 grid with spacing 8, there can be only a few nodes)
+    for (let i = 0; i < positions.length; i++) {
+      for (let j = i + 1; j < positions.length; j++) {
+        const dx = positions[i].x - positions[j].x;
+        const dy = positions[i].y - positions[j].y;
+        const dist = Math.sqrt(dx * dx + dy * dy);
+        expect(dist).toBeGreaterThanOrEqual(7); // slight tolerance
+      }
+    }
+  });
+});

tests/player.test.ts

@@ -0,0 +1,409 @@
+/**
+ * Player Systems Tests — Phase 4.1
+ *
+ * Tests pure logic functions: input → velocity, tile collision,
+ * spawn position finding, and player entity creation.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { createWorld, addEntity, addComponent, query } from 'bitecs';
+import { Position, Velocity, PlayerTag, Health, SpriteRef } from '../src/ecs/components';
+import { calculatePlayerVelocity, playerInputSystem } from '../src/player/input';
+import { PLAYER_SPEED, PLAYER_COLLISION_RADIUS } from '../src/player/types';
+import {
+  isTileWalkable,
+  isAreaWalkable,
+  resolveCollision,
+  buildWalkableSet,
+  tileCollisionSystem,
+} from '../src/player/collision';
+import { findSpawnPosition } from '../src/player/spawn';
+import { createPlayerEntity } from '../src/player/factory';
+import type { InputState } from '../src/player/types';
+
+// === Helpers ===
+
+function makeInput(moveX = 0, moveY = 0, interact = false): InputState {
+  return { moveX, moveY, interact };
+}
+
+// === Input: calculatePlayerVelocity ===
+
+describe('calculatePlayerVelocity', () => {
+  it('moves right when moveX = 1', () => {
+    const v = calculatePlayerVelocity(makeInput(1, 0), PLAYER_SPEED);
+    expect(v.vx).toBe(PLAYER_SPEED);
+    expect(v.vy).toBe(0);
+  });
+
+  it('moves left when moveX = -1', () => {
+    const v = calculatePlayerVelocity(makeInput(-1, 0), PLAYER_SPEED);
+    expect(v.vx).toBe(-PLAYER_SPEED);
+    expect(v.vy).toBe(0);
+  });
+
+  it('moves down when moveY = 1', () => {
+    const v = calculatePlayerVelocity(makeInput(0, 1), PLAYER_SPEED);
+    expect(v.vx).toBe(0);
+    expect(v.vy).toBe(PLAYER_SPEED);
+  });
+
+  it('moves up when moveY = -1', () => {
+    const v = calculatePlayerVelocity(makeInput(0, -1), PLAYER_SPEED);
+    expect(v.vx).toBe(0);
+    expect(v.vy).toBe(-PLAYER_SPEED);
+  });
+
+  it('stops when no input', () => {
+    const v = calculatePlayerVelocity(makeInput(0, 0), PLAYER_SPEED);
+    expect(v.vx).toBe(0);
+    expect(v.vy).toBe(0);
+  });
+
+  it('normalizes diagonal movement to same speed', () => {
+    const v = calculatePlayerVelocity(makeInput(1, 1), PLAYER_SPEED);
+    const mag = Math.sqrt(v.vx * v.vx + v.vy * v.vy);
+    expect(mag).toBeCloseTo(PLAYER_SPEED);
+  });
+
+  it('normalizes all four diagonal directions', () => {
+    for (const [mx, my] of [[-1, -1], [-1, 1], [1, -1], [1, 1]]) {
+      const v = calculatePlayerVelocity(makeInput(mx, my), PLAYER_SPEED);
+      const mag = Math.sqrt(v.vx * v.vx + v.vy * v.vy);
+      expect(mag).toBeCloseTo(PLAYER_SPEED);
+    }
+  });
+
+  it('diagonal components are equal in magnitude', () => {
+    const v = calculatePlayerVelocity(makeInput(1, -1), PLAYER_SPEED);
+    expect(Math.abs(v.vx)).toBeCloseTo(Math.abs(v.vy));
+  });
+});
+
+// === Input: playerInputSystem ===
+
+describe('playerInputSystem', () => {
+  it('sets player velocity from input', () => {
+    const world = createWorld();
+    const eid = addEntity(world);
+    addComponent(world, eid, Position);
+    addComponent(world, eid, Velocity);
+    addComponent(world, eid, PlayerTag);
+
+    playerInputSystem(world, makeInput(1, 0));
+
+    expect(Velocity.vx[eid]).toBe(PLAYER_SPEED);
+    expect(Velocity.vy[eid]).toBe(0);
+  });
+
+  it('does not affect non-player entities', () => {
+    const world = createWorld();
+
+    // Player
+    const player = addEntity(world);
+    addComponent(world, player, Position);
+    addComponent(world, player, Velocity);
+    addComponent(world, player, PlayerTag);
+
+    // Non-player with existing velocity
+    const other = addEntity(world);
+    addComponent(world, other, Position);
+    addComponent(world, other, Velocity);
+    Velocity.vx[other] = 50;
+    Velocity.vy[other] = -30;
+
+    playerInputSystem(world, makeInput(0, 1));
+
+    expect(Velocity.vx[player]).toBe(0);
+    expect(Velocity.vy[player]).toBe(PLAYER_SPEED);
+    // Non-player unchanged
+    expect(Velocity.vx[other]).toBe(50);
+    expect(Velocity.vy[other]).toBe(-30);
+  });
+
+  it('stops player when input is zero', () => {
+    const world = createWorld();
+    const eid = addEntity(world);
+    addComponent(world, eid, Position);
+    addComponent(world, eid, Velocity);
+    addComponent(world, eid, PlayerTag);
+    Velocity.vx[eid] = 999;
+    Velocity.vy[eid] = 999;
+
+    playerInputSystem(world, makeInput(0, 0));
+
+    expect(Velocity.vx[eid]).toBe(0);
+    expect(Velocity.vy[eid]).toBe(0);
+  });
+});
+
+// === Collision: isTileWalkable ===
+
+describe('isTileWalkable', () => {
+  const grid = [[0, 0, 0], [0, 3, 0], [0, 0, 0]];
+  const walkable = new Set([0]);
+  const ts = 32;
+
+  it('returns true for walkable tile', () => {
+    expect(isTileWalkable(16, 16, grid, ts, walkable)).toBe(true);
+  });
+
+  it('returns false for non-walkable tile', () => {
+    expect(isTileWalkable(48, 48, grid, ts, walkable)).toBe(false);
+  });
+
+  it('returns false for negative coordinates', () => {
+    expect(isTileWalkable(-1, 16, grid, ts, walkable)).toBe(false);
+    expect(isTileWalkable(16, -1, grid, ts, walkable)).toBe(false);
+  });
+
+  it('returns false for out-of-bounds coordinates', () => {
+    expect(isTileWalkable(96, 16, grid, ts, walkable)).toBe(false);
+    expect(isTileWalkable(16, 96, grid, ts, walkable)).toBe(false);
+  });
+
+  it('handles tile edge boundaries', () => {
+    expect(isTileWalkable(31.9, 16, grid, ts, walkable)).toBe(true); // still tile 0
+    expect(isTileWalkable(32, 16, grid, ts, walkable)).toBe(true); // tile 1 column, row 0 = walkable
+  });
+});
+
+// === Collision: isAreaWalkable ===
+
+describe('isAreaWalkable', () => {
+  const grid = [[0, 0, 0], [0, 3, 0], [0, 0, 0]];
+  const walkable = new Set([0]);
+  const ts = 32;
+  const r = 6;
+
+  it('returns true when area is fully on walkable tiles', () => {
+    expect(isAreaWalkable(16, 16, r, grid, ts, walkable)).toBe(true);
+  });
+
+  it('returns false when area overlaps non-walkable tile', () => {
+    // (26, 26) with r=6 → corner at (32, 32) enters tile (1,1) which is non-walkable
+    expect(isAreaWalkable(26, 26, r, grid, ts, walkable)).toBe(false);
+  });
+
+  it('returns true when near wall but not overlapping', () => {
+    // (24, 16) with r=6 → rightmost point at 30, still in tile 0 column
+    expect(isAreaWalkable(24, 16, r, grid, ts, walkable)).toBe(true);
+  });
+});
+
+// === Collision: resolveCollision ===
+
+describe('resolveCollision', () => {
+  const ts = 32;
+  const r = 6;
+  const walkable = new Set([0]);
+
+  it('allows movement to valid position', () => {
+    const grid = [[0, 0, 0], [0, 0, 0], [0, 0, 0]];
+    const result = resolveCollision(48, 48, 16, 16, r, grid, ts, walkable);
+    expect(result).toEqual({ x: 48, y: 48 });
+  });
+
+  it('blocks movement into non-walkable tile (slides X when Y row is clear)', () => {
+    // Center tile non-walkable but row 0 at X=48 is walkable → slides X
+    const grid = [[0, 0, 0], [0, 3, 0], [0, 0, 0]];
+    const result = resolveCollision(48, 48, 16, 16, r, grid, ts, walkable);
+    expect(result).toEqual({ x: 48, y: 16 }); // slides along X
+  });
+
+  it('fully blocks when both axes lead to non-walkable', () => {
+    // "+" shaped wall: column 1 and row 1 are non-walkable
+    const grid = [[0, 3, 0], [3, 3, 3], [0, 3, 0]];
+    const result = resolveCollision(48, 48, 16, 16, r, grid, ts, walkable);
+    expect(result).toEqual({ x: 16, y: 16 }); // can't move at all
+  });
+
+  it('wall-slides along X when Y is blocked', () => {
+    // Top row is wall, rows 1-2 walkable
+    const grid = [[3, 3, 3], [0, 0, 0], [0, 0, 0]];
+    // From (48, 48) try to go to (60, 22) — Y into wall, X along wall
+    // Full: blocked (y-r=16 hits row 0)
+    // X-only: (60, 48) → all in row 1 → valid
+    const result = resolveCollision(60, 22, 48, 48, r, grid, ts, walkable);
+    expect(result).toEqual({ x: 60, y: 48 });
+  });
+
+  it('wall-slides along Y when X is blocked', () => {
+    // Left column is wall, columns 1-2 walkable
+    const grid = [[3, 0, 0], [3, 0, 0], [3, 0, 0]];
+    // From (48, 48) try to go to (22, 60) — X into wall, Y along wall
+    // Full: blocked (x-r=16 hits col 0)
+    // X-only: (22, 48) → blocked
+    // Y-only: (48, 60) → all in col 1 → valid
+    const result = resolveCollision(22, 60, 48, 48, r, grid, ts, walkable);
+    expect(result).toEqual({ x: 48, y: 60 });
+  });
+
+  it('reverts completely when both axes blocked', () => {
+    // Only center tile walkable, rest walls
+    const grid = [[3, 3, 3], [3, 0, 3], [3, 3, 3]];
+    // From (48, 48) try to go to (80, 80) — off walkable area
+    const result = resolveCollision(80, 80, 48, 48, r, grid, ts, walkable);
+    expect(result).toEqual({ x: 48, y: 48 });
+  });
+
+  it('blocks out-of-bounds movement', () => {
+    const grid = [[0, 0], [0, 0]];
+    const result = resolveCollision(-5, 16, 16, 16, r, grid, ts, walkable);
+    expect(result).toEqual({ x: 16, y: 16 });
+  });
+});
+
+// === Collision: tileCollisionSystem ===
+
+describe('tileCollisionSystem', () => {
+  it('corrects player position after invalid movement', () => {
+    const world = createWorld();
+    const eid = addEntity(world);
+    addComponent(world, eid, Position);
+    addComponent(world, eid, Velocity);
+    addComponent(world, eid, PlayerTag);
+
+    // Player at (48, 48) with velocity that would move into wall
+    // After movementSystem: Position was updated. We simulate the post-movement state.
+    Velocity.vx[eid] = 150; // moving right
+    Velocity.vy[eid] = 0;
+    // After 0.2s movement: moved 30px right to x=78 which is in tile (2,1)
+    Position.x[eid] = 78;
+    Position.y[eid] = 48;
+
+    // Grid where tile (2,1) is non-walkable
+    const grid = [[0, 0, 3], [0, 0, 3], [0, 0, 3]];
+    const walkable = new Set([0]);
+
+    tileCollisionSystem(world, 200, grid, 32, walkable);
+
+    // Should revert X (back to 48)
+    expect(Position.x[eid]).toBe(48);
+    expect(Position.y[eid]).toBe(48);
+  });
+});
+
+// === Collision: buildWalkableSet ===
+
+describe('buildWalkableSet', () => {
+  it('includes walkable tiles', () => {
+    const tiles = [
+      { id: 0, walkable: true },
+      { id: 1, walkable: true },
+      { id: 3, walkable: false },
+    ];
+    const set = buildWalkableSet(tiles);
+    expect(set.has(0)).toBe(true);
+    expect(set.has(1)).toBe(true);
+    expect(set.has(3)).toBe(false);
+  });
+
+  it('returns empty set when no walkable tiles', () => {
+    const tiles = [{ id: 0, walkable: false }];
+    const set = buildWalkableSet(tiles);
+    expect(set.size).toBe(0);
+  });
+});
+
+// === Spawn Position ===
+
+describe('findSpawnPosition', () => {
+  const walkable = new Set([0]);
+  const ts = 32;
+
+  it('finds walkable spawn position', () => {
+    const grid = [[3, 3, 3], [3, 0, 3], [3, 3, 3]];
+    const pos = findSpawnPosition(grid, ts, walkable);
+    expect(pos).not.toBeNull();
+    const tx = Math.floor(pos!.x / ts);
+    const ty = Math.floor(pos!.y / ts);
+    expect(walkable.has(grid[ty][tx])).toBe(true);
+  });
+
+  it('prefers center of map', () => {
+    const grid = [
+      [0, 0, 0, 0, 0],
+      [0, 0, 0, 0, 0],
+      [0, 0, 0, 0, 0],
+      [0, 0, 0, 0, 0],
+      [0, 0, 0, 0, 0],
+    ];
+    const pos = findSpawnPosition(grid, ts, walkable);
+    expect(pos).not.toBeNull();
+    const tx = Math.floor(pos!.x / ts);
+    const ty = Math.floor(pos!.y / ts);
+    expect(tx).toBe(2);
+    expect(ty).toBe(2);
+  });
+
+  it('returns null for fully non-walkable grid', () => {
+    const grid = [[3, 3], [3, 3]];
+    const pos = findSpawnPosition(grid, ts, walkable);
+    expect(pos).toBeNull();
+  });
+
+  it('spirals outward to find walkable tile', () => {
+    // Center (2,2) is non-walkable, but neighbors are
+    const grid = [
+      [0, 0, 0, 0, 0],
+      [0, 3, 3, 3, 0],
+      [0, 3, 3, 3, 0],
+      [0, 3, 3, 3, 0],
+      [0, 0, 0, 0, 0],
+    ];
+    const pos = findSpawnPosition(grid, ts, walkable);
+    expect(pos).not.toBeNull();
+    // Should find one of the ring-1 tiles (first walkable on spiral)
+    const tx = Math.floor(pos!.x / ts);
+    const ty = Math.floor(pos!.y / ts);
+    expect(walkable.has(grid[ty][tx])).toBe(true);
+  });
+
+  it('returns center of tile in pixels', () => {
+    const grid = [[0]];
+    const pos = findSpawnPosition(grid, ts, walkable);
+    expect(pos).toEqual({ x: 16, y: 16 }); // center of tile (0,0) = (16, 16)
+  });
+});
+
+// === Player Entity Factory ===
+
+describe('createPlayerEntity', () => {
+  it('creates entity with correct position', () => {
+    const world = createWorld();
+    const eid = createPlayerEntity(world, 100, 200);
+    expect(Position.x[eid]).toBe(100);
+    expect(Position.y[eid]).toBe(200);
+  });
+
+  it('creates entity with health', () => {
+    const world = createWorld();
+    const eid = createPlayerEntity(world, 0, 0);
+    expect(Health.current[eid]).toBeGreaterThan(0);
+    expect(Health.max[eid]).toBeGreaterThan(0);
+    expect(Health.current[eid]).toBe(Health.max[eid]);
+  });
+
+  it('creates entity with sprite', () => {
+    const world = createWorld();
+    const eid = createPlayerEntity(world, 0, 0);
+    expect(SpriteRef.color[eid]).toBeDefined();
+    expect(SpriteRef.radius[eid]).toBeGreaterThan(0);
+  });
+
+  it('creates entity queryable with PlayerTag', () => {
+    const world = createWorld();
+    const eid = createPlayerEntity(world, 50, 50);
+    const players = query(world, [PlayerTag]);
+    expect(players).toContain(eid);
+    expect(players.length).toBe(1);
+  });
+
+  it('creates entity with velocity component', () => {
+    const world = createWorld();
+    const eid = createPlayerEntity(world, 0, 0);
+    expect(Velocity.vx[eid]).toBe(0);
+    expect(Velocity.vy[eid]).toBe(0);
+  });
+});

tests/projectile.test.ts

@@ -0,0 +1,188 @@
+/**
+ * Projectile System Tests — Phase 4.5
+ *
+ * Tests: projectile creation, direction calculation,
+ * lifetime expiry, tile collision removal.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { createWorld, addEntity, addComponent, query } from 'bitecs';
+import { Position, Velocity, Projectile, SpriteRef } from '../src/ecs/components';
+import {
+  launchProjectile,
+  projectileSystem,
+  calculateDirection,
+  type ProjectileData,
+  PROJECTILE_SPEED,
+  PROJECTILE_LIFETIME,
+} from '../src/player/projectile';
+
+// === Direction Calculation ===
+
+describe('calculateDirection', () => {
+  it('normalizes direction vector', () => {
+    const d = calculateDirection(0, 0, 100, 0);
+    expect(d.dx).toBeCloseTo(1);
+    expect(d.dy).toBeCloseTo(0);
+  });
+
+  it('handles diagonal direction', () => {
+    const d = calculateDirection(0, 0, 100, 100);
+    const mag = Math.sqrt(d.dx * d.dx + d.dy * d.dy);
+    expect(mag).toBeCloseTo(1);
+  });
+
+  it('handles negative direction', () => {
+    const d = calculateDirection(100, 100, 0, 0);
+    expect(d.dx).toBeCloseTo(-1 / Math.SQRT2);
+    expect(d.dy).toBeCloseTo(-1 / Math.SQRT2);
+  });
+
+  it('returns zero for same position', () => {
+    const d = calculateDirection(50, 50, 50, 50);
+    expect(d.dx).toBe(1); // default to right
+    expect(d.dy).toBe(0);
+  });
+});
+
+// === Launch Projectile ===
+
+describe('launchProjectile', () => {
+  it('creates entity at source position', () => {
+    const world = createWorld();
+    const projData = new Map<number, ProjectileData>();
+
+    const eid = launchProjectile(world, projData, 100, 200, 200, 200, 'Na');
+
+    expect(Position.x[eid]).toBe(100);
+    expect(Position.y[eid]).toBe(200);
+  });
+
+  it('sets velocity toward target', () => {
+    const world = createWorld();
+    const projData = new Map<number, ProjectileData>();
+
+    const eid = launchProjectile(world, projData, 0, 0, 100, 0, 'Na');
+
+    expect(Velocity.vx[eid]).toBeCloseTo(PROJECTILE_SPEED);
+    expect(Velocity.vy[eid]).toBeCloseTo(0);
+  });
+
+  it('stores chemical data', () => {
+    const world = createWorld();
+    const projData = new Map<number, ProjectileData>();
+
+    const eid = launchProjectile(world, projData, 0, 0, 100, 0, 'Na');
+
+    expect(projData.get(eid)).toBeDefined();
+    expect(projData.get(eid)!.itemId).toBe('Na');
+  });
+
+  it('sets lifetime', () => {
+    const world = createWorld();
+    const projData = new Map<number, ProjectileData>();
+
+    const eid = launchProjectile(world, projData, 0, 0, 100, 0, 'Na');
+
+    expect(Projectile.lifetime[eid]).toBe(PROJECTILE_LIFETIME);
+  });
+
+  it('sets sprite with element color', () => {
+    const world = createWorld();
+    const projData = new Map<number, ProjectileData>();
+
+    const eid = launchProjectile(world, projData, 0, 0, 100, 0, 'Na');
+
+    expect(SpriteRef.radius[eid]).toBeGreaterThan(0);
+    expect(SpriteRef.color[eid]).toBeDefined();
+  });
+});
+
+// === Projectile System ===
+
+describe('projectileSystem', () => {
+  it('decrements lifetime', () => {
+    const world = createWorld();
+    const eid = addEntity(world);
+    addComponent(world, eid, Position);
+    addComponent(world, eid, Velocity);
+    addComponent(world, eid, Projectile);
+    Position.x[eid] = 48;
+    Position.y[eid] = 48;
+    Velocity.vx[eid] = 100;
+    Velocity.vy[eid] = 0;
+    Projectile.lifetime[eid] = 1000;
+
+    const grid = [[0, 0, 0], [0, 0, 0], [0, 0, 0]];
+    const walkable = new Set([0]);
+    const projData = new Map<number, ProjectileData>();
+    projData.set(eid, { itemId: 'Na' });
+
+    projectileSystem(world, 100, grid, 32, walkable, projData);
+
+    expect(Projectile.lifetime[eid]).toBe(900);
+  });
+
+  it('removes expired projectiles', () => {
+    const world = createWorld();
+    const eid = addEntity(world);
+    addComponent(world, eid, Position);
+    addComponent(world, eid, Velocity);
+    addComponent(world, eid, Projectile);
+    Position.x[eid] = 48;
+    Position.y[eid] = 48;
+    Projectile.lifetime[eid] = 50;
+
+    const grid = [[0, 0, 0], [0, 0, 0], [0, 0, 0]];
+    const walkable = new Set([0]);
+    const projData = new Map<number, ProjectileData>();
+    projData.set(eid, { itemId: 'Na' });
+
+    projectileSystem(world, 100, grid, 32, walkable, projData);
+
+    expect(query(world, [Projectile]).length).toBe(0);
+    expect(projData.size).toBe(0);
+  });
+
+  it('removes projectiles on non-walkable tile', () => {
+    const world = createWorld();
+    const eid = addEntity(world);
+    addComponent(world, eid, Position);
+    addComponent(world, eid, Velocity);
+    addComponent(world, eid, Projectile);
+    // Position on non-walkable tile (1,1) = tile 3
+    Position.x[eid] = 48;
+    Position.y[eid] = 48;
+    Projectile.lifetime[eid] = 5000;
+
+    const grid = [[0, 0, 0], [0, 3, 0], [0, 0, 0]];
+    const walkable = new Set([0]);
+    const projData = new Map<number, ProjectileData>();
+    projData.set(eid, { itemId: 'Na' });
+
+    projectileSystem(world, 16, grid, 32, walkable, projData);
+
+    expect(query(world, [Projectile]).length).toBe(0);
+  });
+
+  it('keeps valid projectiles alive', () => {
+    const world = createWorld();
+    const eid = addEntity(world);
+    addComponent(world, eid, Position);
+    addComponent(world, eid, Velocity);
+    addComponent(world, eid, Projectile);
+    Position.x[eid] = 48;
+    Position.y[eid] = 48;
+    Projectile.lifetime[eid] = 5000;
+
+    const grid = [[0, 0, 0], [0, 0, 0], [0, 0, 0]];
+    const walkable = new Set([0]);
+    const projData = new Map<number, ProjectileData>();
+    projData.set(eid, { itemId: 'Na' });
+
+    projectileSystem(world, 16, grid, 32, walkable, projData);
+
+    expect(query(world, [Projectile]).length).toBe(1);
+    expect(projData.size).toBe(1);
+  });
+});

tests/quickslots.test.ts

@@ -0,0 +1,131 @@
+/**
+ * Quick Slots Tests — Phase 4.6
+ *
+ * Tests: slot assignment, active selection, key switching.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { QuickSlots, SLOT_COUNT } from '../src/player/quickslots';
+
+describe('QuickSlots — creation', () => {
+  it('starts with all slots empty', () => {
+    const qs = new QuickSlots();
+    for (let i = 0; i < SLOT_COUNT; i++) {
+      expect(qs.getSlot(i)).toBeNull();
+    }
+  });
+
+  it('starts with slot 0 active', () => {
+    const qs = new QuickSlots();
+    expect(qs.activeIndex).toBe(0);
+  });
+
+  it('has 4 slots', () => {
+    expect(SLOT_COUNT).toBe(4);
+    const qs = new QuickSlots();
+    expect(qs.getAll()).toHaveLength(4);
+  });
+});
+
+describe('QuickSlots — assignment', () => {
+  it('assigns item to slot', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    expect(qs.getSlot(0)).toBe('Na');
+  });
+
+  it('replaces existing item in slot', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    qs.assign(0, 'Fe');
+    expect(qs.getSlot(0)).toBe('Fe');
+  });
+
+  it('clears slot with null', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    qs.assign(0, null);
+    expect(qs.getSlot(0)).toBeNull();
+  });
+
+  it('ignores invalid index', () => {
+    const qs = new QuickSlots();
+    qs.assign(-1, 'Na');
+    qs.assign(4, 'Na');
+    // No crash, no change
+    expect(qs.getAll()).toEqual([null, null, null, null]);
+  });
+});
+
+describe('QuickSlots — active slot', () => {
+  it('returns active slot item', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    expect(qs.getActive()).toBe('Na');
+  });
+
+  it('returns null for empty active slot', () => {
+    const qs = new QuickSlots();
+    expect(qs.getActive()).toBeNull();
+  });
+
+  it('switches active slot', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    qs.assign(1, 'Fe');
+    qs.assign(2, 'Cu');
+
+    qs.setActive(1);
+    expect(qs.activeIndex).toBe(1);
+    expect(qs.getActive()).toBe('Fe');
+
+    qs.setActive(2);
+    expect(qs.getActive()).toBe('Cu');
+  });
+
+  it('clamps active index to valid range', () => {
+    const qs = new QuickSlots();
+    qs.setActive(-1);
+    expect(qs.activeIndex).toBe(0);
+
+    qs.setActive(10);
+    expect(qs.activeIndex).toBe(3);
+  });
+});
+
+describe('QuickSlots — getAll', () => {
+  it('returns snapshot of all slots', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    qs.assign(2, 'Fe');
+    expect(qs.getAll()).toEqual(['Na', null, 'Fe', null]);
+  });
+});
+
+describe('QuickSlots — auto-assign', () => {
+  it('assigns to first empty slot', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    const index = qs.autoAssign('Fe');
+    expect(index).toBe(1);
+    expect(qs.getSlot(1)).toBe('Fe');
+  });
+
+  it('returns -1 when all slots full', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    qs.assign(1, 'Fe');
+    qs.assign(2, 'Cu');
+    qs.assign(3, 'S');
+    const index = qs.autoAssign('H');
+    expect(index).toBe(-1);
+  });
+
+  it('does not duplicate item already in a slot', () => {
+    const qs = new QuickSlots();
+    qs.assign(0, 'Na');
+    const index = qs.autoAssign('Na');
+    expect(index).toBe(-1); // already assigned
+    expect(qs.getAll().filter(s => s === 'Na')).toHaveLength(1);
+  });
+});

tests/run-cycle.test.ts

@@ -0,0 +1,627 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import schoolsData from '../src/data/schools.json';
+import elementsData from '../src/data/elements.json';
+import type { SchoolData, RunState, MetaState, CrisisConfig } from '../src/run/types';
+import {
+  RunPhase,
+  RUN_PHASE_NAMES,
+  BODY_COMPOSITION,
+  SPORE_REWARDS,
+  PHASE_DURATIONS,
+  ESCALATION_RATE,
+} from '../src/run/types';
+import {
+  createRunState,
+  advancePhase,
+  updateEscalation,
+  recordDiscovery,
+  calculateSpores,
+} from '../src/run/state';
+import {
+  createMetaState,
+  applyRunResults,
+  isSchoolUnlocked,
+  getCodexEntries,
+  getCodexCount,
+  checkSchoolUnlocks,
+  getSchoolBonuses,
+} from '../src/run/meta';
+import {
+  createCrisisState,
+  applyCrisisDamage,
+  attemptNeutralize,
+  isCrisisResolved,
+  CHEMICAL_PLAGUE,
+} from '../src/run/crisis';
+
+// ─── School Data ─────────────────────────────────────────────────
+
+describe('School Data', () => {
+  const schools = schoolsData as SchoolData[];
+
+  it('should have exactly 4 schools', () => {
+    expect(schools.length).toBe(4);
+  });
+
+  it('Alchemist has correct starting elements', () => {
+    const alchemist = schools.find(s => s.id === 'alchemist');
+    expect(alchemist).toBeDefined();
+    expect(alchemist!.startingElements).toEqual(['H', 'O', 'C', 'Na', 'S', 'Fe']);
+  });
+
+  it('Mechanic has correct starting elements', () => {
+    const mechanic = schools.find(s => s.id === 'mechanic');
+    expect(mechanic).toBeDefined();
+    expect(mechanic!.startingElements).toEqual(['Fe', 'Cu', 'Sn', 'Si', 'C']);
+  });
+
+  it('Naturalist has correct starting elements', () => {
+    const naturalist = schools.find(s => s.id === 'naturalist');
+    expect(naturalist).toBeDefined();
+    expect(naturalist!.startingElements).toEqual(['C', 'N', 'O', 'P', 'K']);
+  });
+
+  it('Navigator has correct starting elements', () => {
+    const navigator = schools.find(s => s.id === 'navigator');
+    expect(navigator).toBeDefined();
+    expect(navigator!.startingElements).toEqual(['Si', 'Fe', 'C', 'H', 'O']);
+  });
+
+  it('all starting elements exist in element registry', () => {
+    const symbols = new Set(elementsData.map(e => e.symbol));
+    for (const school of schools) {
+      for (const elem of school.startingElements) {
+        expect(symbols.has(elem), `Element ${elem} not found in registry`).toBe(true);
+      }
+    }
+  });
+
+  it('starting quantities match starting elements', () => {
+    for (const school of schools) {
+      for (const elem of school.startingElements) {
+        expect(
+          school.startingQuantities[elem],
+          `Missing quantity for ${elem} in school ${school.id}`,
+        ).toBeGreaterThan(0);
+      }
+    }
+  });
+
+  it('each school has bilingual fields', () => {
+    for (const school of schools) {
+      expect(school.name.length).toBeGreaterThan(0);
+      expect(school.nameRu.length).toBeGreaterThan(0);
+      expect(school.description.length).toBeGreaterThan(0);
+      expect(school.descriptionRu.length).toBeGreaterThan(0);
+      expect(school.principle.length).toBeGreaterThan(0);
+      expect(school.principleRu.length).toBeGreaterThan(0);
+    }
+  });
+
+  it('each school has a valid hex color', () => {
+    for (const school of schools) {
+      expect(school.color).toMatch(/^#[0-9a-fA-F]{6}$/);
+    }
+  });
+
+  it('each school has unique id', () => {
+    const ids = schools.map(s => s.id);
+    expect(new Set(ids).size).toBe(ids.length);
+  });
+
+  it('each school has unique color', () => {
+    const colors = schools.map(s => s.color);
+    expect(new Set(colors).size).toBe(colors.length);
+  });
+
+  it('each school has bonuses defined', () => {
+    for (const school of schools) {
+      expect(school.bonuses).toBeDefined();
+      expect(Object.keys(school.bonuses).length).toBeGreaterThan(0);
+    }
+  });
+
+  it('locked schools have unlock conditions', () => {
+    for (const school of schools) {
+      if (school.id === 'alchemist') {
+        expect(school.unlockCondition).toBeUndefined();
+      } else {
+        expect(school.unlockCondition).toBeDefined();
+        expect(school.unlockCondition!.threshold).toBeGreaterThan(0);
+        expect(school.unlockCondition!.hint.length).toBeGreaterThan(0);
+        expect(school.unlockCondition!.hintRu.length).toBeGreaterThan(0);
+      }
+    }
+  });
+
+  it('each school has a real scientific principle', () => {
+    const alchemist = schools.find(s => s.id === 'alchemist')!;
+    expect(alchemist.principle).toBe('Chemical Equilibrium');
+
+    const mechanic = schools.find(s => s.id === 'mechanic')!;
+    expect(mechanic.principle).toBe('Lever & Moment of Force');
+
+    const naturalist = schools.find(s => s.id === 'naturalist')!;
+    expect(naturalist.principle).toBe('Photosynthesis');
+
+    const navigator = schools.find(s => s.id === 'navigator')!;
+    expect(navigator.principle).toBe('Angular Measurement');
+  });
+});
+
+// ─── Run State ───────────────────────────────────────────────────
+
+describe('Run State', () => {
+  let state: RunState;
+
+  beforeEach(() => {
+    state = createRunState(1, 'alchemist');
+  });
+
+  it('creates initial state in Awakening phase', () => {
+    expect(state.runId).toBe(1);
+    expect(state.schoolId).toBe('alchemist');
+    expect(state.phase).toBe(RunPhase.Awakening);
+    expect(state.elapsed).toBe(0);
+    expect(state.escalation).toBe(0);
+    expect(state.crisisActive).toBe(false);
+    expect(state.alive).toBe(true);
+  });
+
+  it('advances phases in order', () => {
+    advancePhase(state);
+    expect(state.phase).toBe(RunPhase.Exploration);
+
+    advancePhase(state);
+    expect(state.phase).toBe(RunPhase.Escalation);
+
+    advancePhase(state);
+    expect(state.phase).toBe(RunPhase.Crisis);
+
+    advancePhase(state);
+    expect(state.phase).toBe(RunPhase.Resolution);
+  });
+
+  it('does not advance past Resolution', () => {
+    state.phase = RunPhase.Resolution;
+    advancePhase(state);
+    expect(state.phase).toBe(RunPhase.Resolution);
+  });
+
+  it('resets phase timer on advance', () => {
+    state.phaseTimer = 5000;
+    advancePhase(state);
+    expect(state.phaseTimer).toBe(0);
+  });
+
+  it('records element discovery', () => {
+    recordDiscovery(state, 'element', 'Na');
+    expect(state.discoveries.elements.has('Na')).toBe(true);
+  });
+
+  it('records reaction discovery', () => {
+    recordDiscovery(state, 'reaction', 'Na+Cl');
+    expect(state.discoveries.reactions.has('Na+Cl')).toBe(true);
+  });
+
+  it('records compound discovery', () => {
+    recordDiscovery(state, 'compound', 'NaCl');
+    expect(state.discoveries.compounds.has('NaCl')).toBe(true);
+  });
+
+  it('records creature discovery', () => {
+    recordDiscovery(state, 'creature', 'crystallid');
+    expect(state.discoveries.creatures.has('crystallid')).toBe(true);
+  });
+
+  it('does not duplicate discoveries', () => {
+    recordDiscovery(state, 'element', 'Na');
+    recordDiscovery(state, 'element', 'Na');
+    expect(state.discoveries.elements.size).toBe(1);
+  });
+
+  it('calculates spores from discoveries', () => {
+    recordDiscovery(state, 'element', 'Na');
+    recordDiscovery(state, 'element', 'Cl');
+    recordDiscovery(state, 'reaction', 'Na+Cl');
+    recordDiscovery(state, 'compound', 'NaCl');
+    recordDiscovery(state, 'creature', 'crystallid');
+
+    const spores = calculateSpores(state);
+    const expected = 2 * SPORE_REWARDS.element
+      + 1 * SPORE_REWARDS.reaction
+      + 1 * SPORE_REWARDS.compound
+      + 1 * SPORE_REWARDS.creature;
+    expect(spores).toBe(expected);
+  });
+
+  it('adds crisis resolved bonus to spores', () => {
+    recordDiscovery(state, 'element', 'Na');
+    state.crisisResolved = true;
+    const spores = calculateSpores(state);
+    expect(spores).toBe(SPORE_REWARDS.element + SPORE_REWARDS.crisisResolved);
+  });
+});
+
+// ─── Escalation ──────────────────────────────────────────────────
+
+describe('Escalation', () => {
+  let state: RunState;
+
+  beforeEach(() => {
+    state = createRunState(1, 'alchemist');
+    state.phase = RunPhase.Escalation;
+  });
+
+  it('increases escalation over time', () => {
+    updateEscalation(state, 1000); // 1 second
+    expect(state.escalation).toBeCloseTo(ESCALATION_RATE);
+  });
+
+  it('clamps escalation to 1.0', () => {
+    updateEscalation(state, 300_000); // 5 minutes
+    expect(state.escalation).toBeLessThanOrEqual(1.0);
+  });
+
+  it('does not escalate during Exploration', () => {
+    state.phase = RunPhase.Exploration;
+    updateEscalation(state, 10_000);
+    expect(state.escalation).toBe(0);
+  });
+
+  it('continues escalation during Crisis', () => {
+    state.phase = RunPhase.Crisis;
+    state.escalation = 0.5;
+    updateEscalation(state, 1000);
+    expect(state.escalation).toBeGreaterThan(0.5);
+  });
+});
+
+// ─── Meta-Progression ────────────────────────────────────────────
+
+describe('Meta-Progression', () => {
+  let meta: MetaState;
+
+  beforeEach(() => {
+    meta = createMetaState();
+  });
+
+  it('creates empty meta state', () => {
+    expect(meta.spores).toBe(0);
+    expect(meta.codex).toEqual([]);
+    expect(meta.totalRuns).toBe(0);
+    expect(meta.totalDeaths).toBe(0);
+    expect(meta.unlockedSchools).toEqual(['alchemist']);
+  });
+
+  it('alchemist is unlocked by default', () => {
+    expect(isSchoolUnlocked(meta, 'alchemist')).toBe(true);
+  });
+
+  it('other schools are locked by default', () => {
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(false);
+  });
+
+  it('applies run results — adds spores', () => {
+    const run = createRunState(1, 'alchemist');
+    recordDiscovery(run, 'element', 'Na');
+    recordDiscovery(run, 'element', 'Cl');
+
+    applyRunResults(meta, run);
+    expect(meta.spores).toBe(2 * SPORE_REWARDS.element);
+    expect(meta.totalRuns).toBe(1);
+    expect(meta.totalDeaths).toBe(1);
+  });
+
+  it('applies run results — adds codex entries', () => {
+    const run = createRunState(1, 'alchemist');
+    recordDiscovery(run, 'element', 'Na');
+    recordDiscovery(run, 'reaction', 'Na+Cl');
+
+    applyRunResults(meta, run);
+    expect(meta.codex.length).toBe(2);
+    expect(getCodexEntries(meta, 'element')).toHaveLength(1);
+    expect(getCodexEntries(meta, 'reaction')).toHaveLength(1);
+  });
+
+  it('does not duplicate codex entries across runs', () => {
+    const run1 = createRunState(1, 'alchemist');
+    recordDiscovery(run1, 'element', 'Na');
+    applyRunResults(meta, run1);
+
+    const run2 = createRunState(2, 'alchemist');
+    recordDiscovery(run2, 'element', 'Na');
+    applyRunResults(meta, run2);
+
+    expect(getCodexCount(meta)).toBe(1);
+  });
+
+  it('accumulates spores across runs', () => {
+    const run1 = createRunState(1, 'alchemist');
+    recordDiscovery(run1, 'element', 'Na');
+    applyRunResults(meta, run1);
+
+    const run2 = createRunState(2, 'alchemist');
+    recordDiscovery(run2, 'element', 'Cl');
+    applyRunResults(meta, run2);
+
+    expect(meta.spores).toBe(2 * SPORE_REWARDS.element);
+    expect(meta.totalRuns).toBe(2);
+  });
+
+  it('stores run history summaries', () => {
+    const run = createRunState(1, 'alchemist');
+    run.phase = RunPhase.Escalation;
+    run.elapsed = 120_000;
+    recordDiscovery(run, 'element', 'Na');
+    recordDiscovery(run, 'compound', 'NaCl');
+
+    applyRunResults(meta, run);
+    expect(meta.runHistory).toHaveLength(1);
+    expect(meta.runHistory[0].schoolId).toBe('alchemist');
+    expect(meta.runHistory[0].discoveries).toBe(2);
+    expect(meta.runHistory[0].duration).toBe(120_000);
+  });
+});
+
+// ─── Crisis: Chemical Plague ─────────────────────────────────────
+
+describe('Crisis: Chemical Plague', () => {
+  it('defines chemical plague config', () => {
+    expect(CHEMICAL_PLAGUE.type).toBe('chemical-plague');
+    expect(CHEMICAL_PLAGUE.neutralizer).toBeDefined();
+    expect(CHEMICAL_PLAGUE.neutralizeAmount).toBeGreaterThan(0);
+  });
+
+  it('creates crisis state', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    expect(crisis.active).toBe(true);
+    expect(crisis.progress).toBe(0);
+    expect(crisis.resolved).toBe(false);
+  });
+
+  it('applies crisis damage over time', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    applyCrisisDamage(crisis, 1000);
+    expect(crisis.progress).toBeGreaterThan(0);
+  });
+
+  it('crisis progress clamps at 1.0', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    applyCrisisDamage(crisis, 999_999);
+    expect(crisis.progress).toBeLessThanOrEqual(1.0);
+  });
+
+  it('neutralize reduces progress', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.5;
+    const result = attemptNeutralize(crisis, CHEMICAL_PLAGUE.neutralizer, 1);
+    expect(result).toBe(true);
+    expect(crisis.progress).toBeLessThan(0.5);
+  });
+
+  it('wrong compound does not neutralize', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.5;
+    const result = attemptNeutralize(crisis, 'WrongCompound', 1);
+    expect(result).toBe(false);
+    expect(crisis.progress).toBe(0.5);
+  });
+
+  it('sufficient neutralization resolves crisis', () => {
+    const crisis = createCrisisState(CHEMICAL_PLAGUE);
+    crisis.progress = 0.1;
+    attemptNeutralize(crisis, CHEMICAL_PLAGUE.neutralizer, CHEMICAL_PLAGUE.neutralizeAmount);
+    expect(isCrisisResolved(crisis)).toBe(true);
+    expect(crisis.resolved).toBe(true);
+  });
+});
+
+// ─── School Unlock System ────────────────────────────────────────
+
+describe('School Unlock System', () => {
+  let meta: MetaState;
+
+  beforeEach(() => {
+    meta = createMetaState();
+  });
+
+  it('only alchemist is unlocked at start', () => {
+    expect(meta.unlockedSchools).toEqual(['alchemist']);
+  });
+
+  it('mechanic unlocks after discovering 10 elements', () => {
+    const run = createRunState(1, 'alchemist');
+    for (const sym of ['H', 'O', 'C', 'Na', 'S', 'Fe', 'Cu', 'Si', 'Sn', 'N']) {
+      recordDiscovery(run, 'element', sym);
+    }
+    applyRunResults(meta, run);
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(true);
+  });
+
+  it('mechanic does NOT unlock with fewer than 10 elements', () => {
+    const run = createRunState(1, 'alchemist');
+    for (const sym of ['H', 'O', 'C', 'Na', 'S']) {
+      recordDiscovery(run, 'element', sym);
+    }
+    applyRunResults(meta, run);
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(false);
+  });
+
+  it('naturalist unlocks after discovering 3 creatures', () => {
+    const run = createRunState(1, 'alchemist');
+    recordDiscovery(run, 'creature', 'crystallid');
+    recordDiscovery(run, 'creature', 'acidophile');
+    recordDiscovery(run, 'creature', 'reagent');
+    applyRunResults(meta, run);
+    expect(isSchoolUnlocked(meta, 'naturalist')).toBe(true);
+  });
+
+  it('naturalist does NOT unlock with fewer than 3 creatures', () => {
+    const run = createRunState(1, 'alchemist');
+    recordDiscovery(run, 'creature', 'crystallid');
+    recordDiscovery(run, 'creature', 'acidophile');
+    applyRunResults(meta, run);
+    expect(isSchoolUnlocked(meta, 'naturalist')).toBe(false);
+  });
+
+  it('navigator unlocks after 3 completed runs', () => {
+    for (let i = 1; i <= 3; i++) {
+      const run = createRunState(i, 'alchemist');
+      recordDiscovery(run, 'element', `elem${i}`);
+      applyRunResults(meta, run);
+    }
+    expect(isSchoolUnlocked(meta, 'navigator')).toBe(true);
+  });
+
+  it('navigator does NOT unlock with only 2 runs', () => {
+    for (let i = 1; i <= 2; i++) {
+      const run = createRunState(i, 'alchemist');
+      recordDiscovery(run, 'element', `elem${i}`);
+      applyRunResults(meta, run);
+    }
+    expect(isSchoolUnlocked(meta, 'navigator')).toBe(false);
+  });
+
+  it('unlocks persist across subsequent runs', () => {
+    // Unlock mechanic with 10 element discoveries
+    const run1 = createRunState(1, 'alchemist');
+    for (const sym of ['H', 'O', 'C', 'Na', 'S', 'Fe', 'Cu', 'Si', 'Sn', 'N']) {
+      recordDiscovery(run1, 'element', sym);
+    }
+    applyRunResults(meta, run1);
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(true);
+
+    // Next run with no discoveries — mechanic still unlocked
+    const run2 = createRunState(2, 'alchemist');
+    applyRunResults(meta, run2);
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(true);
+  });
+
+  it('multiple schools can unlock in the same run', () => {
+    const run = createRunState(1, 'alchemist');
+    // 10 elements → mechanic
+    for (const sym of ['H', 'O', 'C', 'Na', 'S', 'Fe', 'Cu', 'Si', 'Sn', 'N']) {
+      recordDiscovery(run, 'element', sym);
+    }
+    // 3 creatures → naturalist
+    recordDiscovery(run, 'creature', 'crystallid');
+    recordDiscovery(run, 'creature', 'acidophile');
+    recordDiscovery(run, 'creature', 'reagent');
+
+    applyRunResults(meta, run);
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(true);
+    expect(isSchoolUnlocked(meta, 'naturalist')).toBe(true);
+  });
+
+  it('cumulative codex entries across runs unlock schools', () => {
+    // Run 1: discover 6 elements
+    const run1 = createRunState(1, 'alchemist');
+    for (const sym of ['H', 'O', 'C', 'Na', 'S', 'Fe']) {
+      recordDiscovery(run1, 'element', sym);
+    }
+    applyRunResults(meta, run1);
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(false);
+
+    // Run 2: discover 4 more → total 10
+    const run2 = createRunState(2, 'alchemist');
+    for (const sym of ['Cu', 'Si', 'Sn', 'N']) {
+      recordDiscovery(run2, 'element', sym);
+    }
+    applyRunResults(meta, run2);
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(true);
+  });
+
+  it('checkSchoolUnlocks can be called standalone', () => {
+    // Manually populate codex with 10 elements
+    for (let i = 0; i < 10; i++) {
+      meta.codex.push({ id: `elem${i}`, type: 'element', discoveredOnRun: 1 });
+    }
+    checkSchoolUnlocks(meta);
+    expect(isSchoolUnlocked(meta, 'mechanic')).toBe(true);
+  });
+});
+
+// ─── School Bonuses ──────────────────────────────────────────────
+
+describe('School Bonuses', () => {
+  it('alchemist has reaction efficiency bonus', () => {
+    const bonus = getSchoolBonuses('alchemist');
+    expect(bonus.reactionEfficiency).toBe(1.25);
+    expect(bonus.projectileDamage).toBe(1.0);
+    expect(bonus.movementSpeed).toBe(1.0);
+    expect(bonus.creatureAggroRange).toBe(1.0);
+  });
+
+  it('mechanic has projectile damage bonus', () => {
+    const bonus = getSchoolBonuses('mechanic');
+    expect(bonus.projectileDamage).toBe(1.3);
+    expect(bonus.movementSpeed).toBe(1.0);
+  });
+
+  it('naturalist has creature aggro reduction', () => {
+    const bonus = getSchoolBonuses('naturalist');
+    expect(bonus.creatureAggroRange).toBe(0.6);
+    expect(bonus.projectileDamage).toBe(1.0);
+  });
+
+  it('navigator has movement speed bonus', () => {
+    const bonus = getSchoolBonuses('navigator');
+    expect(bonus.movementSpeed).toBe(1.2);
+    expect(bonus.creatureAggroRange).toBe(1.0);
+  });
+
+  it('unknown school returns all-default bonuses', () => {
+    const bonus = getSchoolBonuses('nonexistent');
+    expect(bonus.projectileDamage).toBe(1.0);
+    expect(bonus.movementSpeed).toBe(1.0);
+    expect(bonus.creatureAggroRange).toBe(1.0);
+    expect(bonus.reactionEfficiency).toBe(1.0);
+  });
+});
+
+// ─── Body Composition ────────────────────────────────────────────
+
+describe('Body Composition', () => {
+  it('fractions sum to approximately 1.0', () => {
+    const sum = BODY_COMPOSITION.reduce((acc, e) => acc + e.fraction, 0);
+    // Allow some margin since we simplified (real body has trace elements)
+    expect(sum).toBeGreaterThan(0.85);
+    expect(sum).toBeLessThanOrEqual(1.0);
+  });
+
+  it('all body elements exist in element registry', () => {
+    const symbols = new Set(elementsData.map(e => e.symbol));
+    for (const entry of BODY_COMPOSITION) {
+      expect(symbols.has(entry.symbol), `${entry.symbol} not in registry`).toBe(true);
+    }
+  });
+
+  it('oxygen is the largest fraction', () => {
+    const oxygen = BODY_COMPOSITION.find(e => e.symbol === 'O');
+    expect(oxygen).toBeDefined();
+    expect(oxygen!.fraction).toBe(0.65);
+  });
+});
+
+// ─── Run Phase Names ─────────────────────────────────────────────
+
+describe('Run Phase Names', () => {
+  it('has names for all phases', () => {
+    expect(RUN_PHASE_NAMES[RunPhase.Awakening]).toBe('Awakening');
+    expect(RUN_PHASE_NAMES[RunPhase.Exploration]).toBe('Exploration');
+    expect(RUN_PHASE_NAMES[RunPhase.Escalation]).toBe('Escalation');
+    expect(RUN_PHASE_NAMES[RunPhase.Crisis]).toBe('Crisis');
+    expect(RUN_PHASE_NAMES[RunPhase.Resolution]).toBe('Resolution');
+  });
+
+  it('phases are numbered 0-4', () => {
+    expect(RunPhase.Awakening).toBe(0);
+    expect(RunPhase.Resolution).toBe(4);
+  });
+
+  it('phase durations are defined', () => {
+    expect(PHASE_DURATIONS[RunPhase.Exploration]).toBeGreaterThan(0);
+    expect(PHASE_DURATIONS[RunPhase.Escalation]).toBeGreaterThan(0);
+  });
+});

tests/ui.test.ts

@@ -0,0 +1,73 @@
+/**
+ * Tests for UIScene helper functions and HUD state contract
+ */
+import { describe, it, expect } from 'vitest';
+import { ElementRegistry } from '../src/chemistry/elements';
+import { CompoundRegistry } from '../src/chemistry/compounds';
+import { QuickSlots, SLOT_COUNT } from '../src/player/quickslots';
+import { Inventory } from '../src/player/inventory';
+import { Health } from '../src/ecs/components';
+
+/** Mirror of UIScene's getItemDisplayColor for testability */
+function getItemDisplayColor(itemId: string): number {
+  const el = ElementRegistry.getBySymbol(itemId);
+  if (el) return parseInt(el.color.replace('#', ''), 16);
+  const comp = CompoundRegistry.getById(itemId);
+  if (comp) return parseInt(comp.color.replace('#', ''), 16);
+  return 0xffffff;
+}
+
+/** Mirror of UIScene's getItemDisplayName for testability */
+function getItemDisplayName(itemId: string): string {
+  const el = ElementRegistry.getBySymbol(itemId);
+  if (el) return el.symbol;
+  const comp = CompoundRegistry.getById(itemId);
+  if (comp) return comp.formula;
+  return itemId;
+}
+
+describe('HUD display helpers', () => {
+  it('getItemDisplayColor returns correct color for element', () => {
+    const color = getItemDisplayColor('Fe');
+    expect(color).toBeGreaterThan(0);
+    expect(color).not.toBe(0xffffff); // Not the fallback
+  });
+
+  it('getItemDisplayColor returns fallback for unknown item', () => {
+    expect(getItemDisplayColor('totally_unknown')).toBe(0xffffff);
+  });
+
+  it('getItemDisplayName returns symbol for element', () => {
+    expect(getItemDisplayName('Fe')).toBe('Fe');
+    expect(getItemDisplayName('Na')).toBe('Na');
+  });
+
+  it('getItemDisplayName returns formula for compound', () => {
+    const name = getItemDisplayName('H2O');
+    expect(name).toBe('H₂O');
+  });
+
+  it('getItemDisplayName returns raw id for unknown', () => {
+    expect(getItemDisplayName('xyz')).toBe('xyz');
+  });
+});
+
+describe('HUD registry state contract', () => {
+  it('QuickSlots.getAll returns array of length SLOT_COUNT', () => {
+    const qs = new QuickSlots();
+    expect(qs.getAll()).toHaveLength(SLOT_COUNT);
+  });
+
+  it('Inventory provides required state fields', () => {
+    const inv = new Inventory(500, 20);
+    expect(typeof inv.getTotalWeight()).toBe('number');
+    expect(typeof inv.maxWeight).toBe('number');
+    expect(typeof inv.slotCount).toBe('number');
+    expect(Array.isArray(inv.getItems())).toBe(true);
+  });
+
+  it('Health component arrays are accessible', () => {
+    expect(Array.isArray(Health.current)).toBe(true);
+    expect(Array.isArray(Health.max)).toBe(true);
+  });
+});

tests/world-traces.test.ts

@@ -0,0 +1,222 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import { createWorld } from 'bitecs';
+import type { GreatCycleState, RunTrace } from '../src/run/types';
+import { RunPhase } from '../src/run/types';
+import { createGreatCycleState } from '../src/run/cycle';
+import { Position, SpriteRef, WorldTrace, TraceType } from '../src/ecs/components';
+import { spawnWorldTraces, updateTraceGlow, type WorldTraceInfo } from '../src/world/traces';
+import biomeData from '../src/data/biomes.json';
+import type { BiomeData } from '../src/world/types';
+
+const biomes = biomeData as BiomeData[];
+const catalyticWastes = biomes.find(b => b.id === 'catalytic-wastes')!;
+
+function makeTrace(
+  runId: number,
+  biomeId: string,
+  deathPos: { tileX: number; tileY: number } | null,
+  discoveryCount: number = 5,
+): RunTrace {
+  return {
+    runId,
+    runInCycle: runId,
+    schoolId: 'alchemist',
+    biomeId,
+    deathPosition: deathPos,
+    phaseReached: RunPhase.Resolution,
+    crisisResolved: false,
+    discoveryCount,
+    keyElements: ['Na', 'O'],
+    duration: 60000,
+    worldSeed: runId * 1000 + 42,
+  };
+}
+
+// ─── World Trace Spawning ────────────────────────────────────────
+
+describe('World Trace Spawning', () => {
+  let world: ReturnType<typeof createWorld>;
+  let cycle: GreatCycleState;
+
+  beforeEach(() => {
+    world = createWorld();
+    cycle = createGreatCycleState();
+  });
+
+  it('should return empty for no traces', () => {
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    expect(result).toEqual([]);
+  });
+
+  it('should spawn death site markers', () => {
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', { tileX: 20, tileY: 30 }),
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    expect(result.length).toBe(1);
+    expect(result[0].traceType).toBe('death_site');
+    expect(result[0].sourceRunId).toBe(1);
+    expect(result[0].tileX).toBe(20);
+    expect(result[0].tileY).toBe(30);
+  });
+
+  it('death site entities should have correct ECS components', () => {
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', { tileX: 10, tileY: 15 }),
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    const eid = result[0].eid;
+
+    // Position at tile center
+    const tileSize = catalyticWastes.tileSize;
+    expect(Position.x[eid]).toBe(10 * tileSize + tileSize / 2);
+    expect(Position.y[eid]).toBe(15 * tileSize + tileSize / 2);
+
+    // Sprite
+    expect(SpriteRef.color[eid]).toBe(0x884444); // dark red for death site
+    expect(SpriteRef.radius[eid]).toBe(6);
+
+    // Trace component
+    expect(WorldTrace.traceType[eid]).toBe(TraceType.DeathSite);
+    expect(WorldTrace.sourceRunId[eid]).toBe(1);
+    expect(WorldTrace.interactRange[eid]).toBe(40);
+  });
+
+  it('should spawn discovery markers for runs without death sites', () => {
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', null, 5), // no death pos, 5 discoveries
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    expect(result.length).toBe(1);
+    expect(result[0].traceType).toBe('discovery_site');
+  });
+
+  it('should NOT spawn discovery markers for low discovery count', () => {
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', null, 2), // only 2 discoveries (< 3 threshold)
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    expect(result.length).toBe(0);
+  });
+
+  it('should prefer death marker over discovery marker for same run', () => {
+    // Run with both death position and discoveries
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', { tileX: 20, tileY: 30 }, 10),
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    // Should only have death_site, not both
+    expect(result.length).toBe(1);
+    expect(result[0].traceType).toBe('death_site');
+  });
+
+  it('should include traces from previous cycle', () => {
+    cycle.previousCycleTraces = [
+      makeTrace(5, 'catalytic-wastes', { tileX: 40, tileY: 50 }),
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    expect(result.length).toBe(1);
+    expect(result[0].sourceRunId).toBe(5);
+  });
+
+  it('should filter by biome', () => {
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', { tileX: 10, tileY: 20 }),
+      makeTrace(2, 'kinetic-mountains', { tileX: 30, tileY: 40 }),
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    expect(result.length).toBe(1);
+    expect(result[0].sourceRunId).toBe(1);
+  });
+
+  it('should clamp death positions to map bounds', () => {
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', { tileX: 9999, tileY: 9999 }),
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    expect(result[0].tileX).toBeLessThan(catalyticWastes.mapWidth);
+    expect(result[0].tileY).toBeLessThan(catalyticWastes.mapHeight);
+  });
+
+  it('should handle multiple traces from multiple runs', () => {
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', { tileX: 10, tileY: 10 }),
+      makeTrace(2, 'catalytic-wastes', { tileX: 30, tileY: 30 }),
+      makeTrace(3, 'catalytic-wastes', null, 8), // discovery only
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    expect(result.length).toBe(3);
+
+    const deathSites = result.filter(r => r.traceType === 'death_site');
+    const discoverySites = result.filter(r => r.traceType === 'discovery_site');
+    expect(deathSites.length).toBe(2);
+    expect(discoverySites.length).toBe(1);
+  });
+});
+
+// ─── Trace Glow Animation ────────────────────────────────────────
+
+describe('Trace Glow Animation', () => {
+  it('should advance glow phase over time', () => {
+    const world = createWorld();
+    const cycle = createGreatCycleState();
+    cycle.currentCycleTraces = [
+      makeTrace(1, 'catalytic-wastes', { tileX: 20, tileY: 30 }),
+    ];
+
+    const result = spawnWorldTraces(world, cycle, 'catalytic-wastes', catalyticWastes);
+    const initialPhase = WorldTrace.glowPhase[result[0].eid];
+
+    updateTraceGlow(result, 1000); // 1 second
+    const newPhase = WorldTrace.glowPhase[result[0].eid];
+
+    expect(newPhase).toBeGreaterThan(initialPhase);
+  });
+});
+
+// ─── Discovery Site Position Determinism ─────────────────────────
+
+describe('Discovery Site Position Determinism', () => {
+  it('same seed should produce same position', () => {
+    const world1 = createWorld();
+    const world2 = createWorld();
+    const cycle1 = createGreatCycleState();
+    const cycle2 = createGreatCycleState();
+
+    const trace = makeTrace(1, 'catalytic-wastes', null, 5);
+    cycle1.currentCycleTraces = [trace];
+    cycle2.currentCycleTraces = [{ ...trace }]; // same data
+
+    const result1 = spawnWorldTraces(world1, cycle1, 'catalytic-wastes', catalyticWastes);
+    const result2 = spawnWorldTraces(world2, cycle2, 'catalytic-wastes', catalyticWastes);
+
+    expect(result1[0].tileX).toBe(result2[0].tileX);
+    expect(result1[0].tileY).toBe(result2[0].tileY);
+  });
+
+  it('different seeds should produce different positions', () => {
+    const world1 = createWorld();
+    const world2 = createWorld();
+    const cycle1 = createGreatCycleState();
+    const cycle2 = createGreatCycleState();
+
+    cycle1.currentCycleTraces = [makeTrace(1, 'catalytic-wastes', null, 5)];
+    cycle2.currentCycleTraces = [makeTrace(99, 'catalytic-wastes', null, 5)]; // different seed
+
+    const result1 = spawnWorldTraces(world1, cycle1, 'catalytic-wastes', catalyticWastes);
+    const result2 = spawnWorldTraces(world2, cycle2, 'catalytic-wastes', catalyticWastes);
+
+    // Very unlikely to be at the same spot with different seeds
+    const sameSpot = result1[0].tileX === result2[0].tileX && result1[0].tileY === result2[0].tileY;
+    expect(sameSpot).toBe(false);
+  });
+});

tests/world.test.ts

@@ -4,8 +4,9 @@ import { createSeededNoise, sampleNoise } from '../src/world/noise';
 import { generateWorld } from '../src/world/generator';
 import type { BiomeData } from '../src/world/types';
 
+const allBiomes = biomeDataArray as BiomeData[];
 // Load the first biome — structural compatibility with BiomeData
-const biome = biomeDataArray[0] as BiomeData;
+const biome = allBiomes[0];
 
 // ─── Noise ──────────────────────────────────────────────────────
 
@@ -181,3 +182,139 @@ describe('World Generation', () => {
     }
   });
 });
+
+// ─── Multi-Biome Support (Phase 9) ──────────────────────────────
+
+describe('Multi-Biome Data', () => {
+  it('has 3 biomes loaded', () => {
+    expect(allBiomes).toHaveLength(3);
+  });
+
+  it('each biome has a unique id', () => {
+    const ids = allBiomes.map(b => b.id);
+    expect(new Set(ids).size).toBe(3);
+    expect(ids).toContain('catalytic-wastes');
+    expect(ids).toContain('kinetic-mountains');
+    expect(ids).toContain('verdant-forests');
+  });
+
+  it('each biome has 8 tile types with sequential IDs', () => {
+    for (const b of allBiomes) {
+      expect(b.tiles).toHaveLength(8);
+      b.tiles.forEach((tile, index) => {
+        expect(tile.id, `${b.id}: tile ${index}`).toBe(index);
+      });
+    }
+  });
+
+  it('each biome has an interactive tile and a resource tile', () => {
+    for (const b of allBiomes) {
+      const interactive = b.tiles.find(t => t.interactive);
+      const resource = b.tiles.find(t => t.resource);
+      expect(interactive, `${b.id}: no interactive tile`).toBeDefined();
+      expect(resource, `${b.id}: no resource tile`).toBeDefined();
+    }
+  });
+
+  it('each biome has valid elevation rules covering [0, 1]', () => {
+    for (const b of allBiomes) {
+      const rules = b.generation.elevationRules;
+      expect(rules.length).toBeGreaterThan(0);
+      expect(rules[rules.length - 1].below).toBe(1);
+      const validIds = new Set(b.tiles.map(t => t.id));
+      for (const rule of rules) {
+        expect(validIds.has(rule.tileId), `${b.id}: invalid tileId ${rule.tileId}`).toBe(true);
+      }
+    }
+  });
+});
+
+describe('Kinetic Mountains Generation', () => {
+  const mtns = allBiomes.find(b => b.id === 'kinetic-mountains')!;
+
+  it('generates correct-size grid', () => {
+    const world = generateWorld(mtns, 42);
+    expect(world.grid).toHaveLength(mtns.mapHeight);
+    expect(world.grid[0]).toHaveLength(mtns.mapWidth);
+  });
+
+  it('all tile IDs are valid', () => {
+    const world = generateWorld(mtns, 42);
+    const validIds = new Set(mtns.tiles.map(t => t.id));
+    for (const row of world.grid) {
+      for (const tileId of row) {
+        expect(validIds.has(tileId)).toBe(true);
+      }
+    }
+  });
+
+  it('has diverse tiles with no single type > 60%', () => {
+    const world = generateWorld(mtns, 42);
+    const counts = new Map<number, number>();
+    for (const row of world.grid) {
+      for (const t of row) counts.set(t, (counts.get(t) ?? 0) + 1);
+    }
+    const total = mtns.mapWidth * mtns.mapHeight;
+    expect(counts.size).toBeGreaterThanOrEqual(4);
+    for (const count of counts.values()) {
+      expect(count / total).toBeLessThan(0.6);
+    }
+  });
+
+  it('generates chasms (low elevation)', () => {
+    const world = generateWorld(mtns, 42);
+    const chasmId = mtns.tiles.find(t => t.name === 'chasm')?.id;
+    expect(world.grid.some(row => row.includes(chasmId!))).toBe(true);
+  });
+
+  it('generates ore deposits (resources)', () => {
+    const world = generateWorld(mtns, 42);
+    const oreId = mtns.tiles.find(t => t.resource)?.id;
+    expect(world.grid.some(row => row.includes(oreId!))).toBe(true);
+  });
+});
+
+describe('Verdant Forests Generation', () => {
+  const forest = allBiomes.find(b => b.id === 'verdant-forests')!;
+
+  it('generates correct-size grid', () => {
+    const world = generateWorld(forest, 42);
+    expect(world.grid).toHaveLength(forest.mapHeight);
+    expect(world.grid[0]).toHaveLength(forest.mapWidth);
+  });
+
+  it('all tile IDs are valid', () => {
+    const world = generateWorld(forest, 42);
+    const validIds = new Set(forest.tiles.map(t => t.id));
+    for (const row of world.grid) {
+      for (const tileId of row) {
+        expect(validIds.has(tileId)).toBe(true);
+      }
+    }
+  });
+
+  it('has diverse tiles with no single type > 60%', () => {
+    const world = generateWorld(forest, 42);
+    const counts = new Map<number, number>();
+    for (const row of world.grid) {
+      for (const t of row) counts.set(t, (counts.get(t) ?? 0) + 1);
+    }
+    const total = forest.mapWidth * forest.mapHeight;
+    expect(counts.size).toBeGreaterThanOrEqual(4);
+    for (const count of counts.values()) {
+      expect(count / total).toBeLessThan(0.6);
+    }
+  });
+
+  it('generates bogs (low elevation)', () => {
+    const world = generateWorld(forest, 42);
+    const bogId = forest.tiles.find(t => t.name === 'bog')?.id;
+    expect(world.grid.some(row => row.includes(bogId!))).toBe(true);
+  });
+
+  it('generates herb patches (resources)', () => {
+    const world = generateWorld(forest, 42);
+    const herbId = forest.tiles.find(t => t.resource)?.id;
+    expect(world.grid.some(row => row.includes(herbId!))).toBe(true);
+  });
+});