diff --git a/src/lib/game/types.ts b/src/lib/game/types.ts
index 10affe1..5993508 100755
--- a/src/lib/game/types.ts
+++ b/src/lib/game/types.ts
@@ -1,516 +1,14 @@
 // ─── Game Types ───────────────────────────────────────────────────────────────
-
-export type ElementCategory = 'base' | 'utility' | 'composite' | 'exotic';
-
-// Attunement body slots
-export type AttunementSlot = 'rightHand' | 'leftHand' | 'head' | 'back' | 'chest' | 'leftLeg' | 'rightLeg';
-
-// Attunement definition
-export interface AttunementDef {
-  id: string;
-  name: string;
-  desc: string;
-  slot: AttunementSlot;
-  icon: string;
-  color: string;
-  primaryManaType?: string;      // Primary mana type this attunement generates (null for Invoker)
-  rawManaRegen: number;          // Raw mana regeneration per hour granted by this attunement
-  conversionRate: number;        // Raw mana converted to primary type per hour
-  unlocked: boolean;             // Whether this is unlocked by default
-  unlockCondition?: string;      // Description of how to unlock (for future challenges)
-  capabilities: string[];        // What this attunement enables (e.g., 'enchanting', 'pacts', 'golemCrafting')
-  skillCategories: string[];     // Skill categories this attunement provides access to
-}
-
-// Attunement instance state (tracks player's attunements)
-export interface AttunementState {
-  id: string;
-  active: boolean;               // Whether this attunement is currently active
-  level: number;                 // Attunement level (for future progression)
-  experience: number;            // Progress toward next level
-}
-
-export interface ElementDef {
-  name: string;
-  sym: string;
-  color: string;
-  glow: string;
-  cat: ElementCategory;
-  recipe?: string[];
-}
-
-export interface ElementState {
-  current: number;
-  max: number;
-  unlocked: boolean;
-}
-
-// Boon types that guardians can grant
-export interface GuardianBoon {
-  type: 'maxMana' | 'manaRegen' | 'castingSpeed' | 'elementalDamage' | 'rawDamage' | 
-        'critChance' | 'critDamage' | 'spellEfficiency' | 'manaGain' | 'insightGain' | 
-        'studySpeed' | 'prestigeInsight';
-  value: number;
-  desc: string;
-}
-
-export interface GuardianDef {
-  name: string;
-  element: string;
-  hp: number;
-  pact: number;           // Pact multiplier when signed
-  color: string;
-  boons: GuardianBoon[];  // Bonuses granted when pact is signed
-  pactCost: number;       // Mana cost to perform pact ritual
-  pactTime: number;       // Hours required for pact ritual
-  uniquePerk: string;     // Description of unique perk
-  armor?: number;         // Damage reduction (0-1, e.g., 0.2 = 20% reduction)
-}
-
-// Spell cost can be raw mana or elemental mana
-export interface SpellCost {
-  type: 'raw' | 'element';  // 'raw' for raw mana, 'element' for specific elemental mana
-  element?: string;          // Required if type is 'element'
-  amount: number;            // Amount of mana required
-}
-
-export interface SpellDef {
-  name: string;
-  elem: string;              // Element type for damage calculations
-  dmg: number;
-  cost: SpellCost;           // Changed from number to SpellCost object
-  tier: number;
-  unlock: number;            // Mana cost to start studying
-  studyTime?: number;        // Hours needed to study (optional, defaults based on tier)
-  castSpeed?: number;        // Casts per hour (default 1, higher = faster)
-  desc?: string;             // Optional spell description
-  effects?: SpellEffect[];   // Optional special effects
-  isAoe?: boolean;           // AOE spell that hits multiple enemies
-  aoeTargets?: number;       // Number of enemies hit by AOE
-  isWeaponEnchant?: boolean; // Can be used as weapon enchantment (magic swords)
-}
-
-export interface SpellEffect {
-  type: 'burn' | 'freeze' | 'stun' | 'pierce' | 'multicast' | 'shield' | 'buff' | 'chain' | 'aoe' | 'armor_pierce';
-  value: number;            // Effect potency
-  duration?: number;        // Duration in hours for timed effects
-  targets?: number;         // For AOE: number of targets
-  chance?: number;          // For chance-based effects (e.g., stun chance)
-}
-
-export interface SpellState {
-  learned: boolean;
-  level: number;
-  studyProgress?: number;   // Hours studied so far (for in-progress spells)
-}
-
-// ─── Room and Enemy Types ─────────────────────────────────────────────────────
-
-export type RoomType = 'combat' | 'puzzle' | 'swarm' | 'speed' | 'guardian';
-
-export interface EnemyState {
-  id: string;
-  hp: number;
-  maxHP: number;
-  armor: number;            // Damage reduction (0-1)
-  dodgeChance: number;      // For speed rooms (0-1)
-  element: string;
-}
-
-export interface FloorState {
-  roomType: RoomType;
-  enemies: EnemyState[];      // For swarm rooms, multiple enemies
-  puzzleProgress?: number;    // For puzzle rooms (0-1)
-  puzzleRequired?: number;    // Total progress needed
-  puzzleId?: string;          // Which puzzle type
-  puzzleAttunements?: string[]; // Which attunements speed up this puzzle
-}
-
-export interface SkillDef {
-  name: string;
-  desc: string;
-  cat: string;
-  attunement?: string;  // Which attunement this skill belongs to (null = core)
-  max: number;
-  base: number;             // Mana cost to start studying
-  req?: Record<string, number>;  // Skill prerequisites
-  attunementReq?: Record<string, number>;  // Attunement level requirements (attunement id -> min level)
-  studyTime: number;        // Hours needed to study
-  level?: number;           // Current level (optional, for UI display)
-  tier?: number;            // Skill tier (1-5)
-  tierUp?: string;          // Skill ID this evolves into at max level
-  baseSkill?: string;       // Original skill ID this evolved from
-  tierMultiplier?: number;  // Multiplier for each tier (default 2)
-}
-
-// Skill upgrade choices at milestones (level 5 and level 10)
-export interface SkillUpgradeDef {
-  id: string;
-  name: string;
-  desc: string;
-  skillId: string;          // Which skill this upgrade belongs to
-  milestone: 5 | 10;        // Level at which this upgrade is available
-  effect: SkillUpgradeEffect;
-}
-
-export interface SkillUpgradeEffect {
-  type: 'multiplier' | 'bonus' | 'special';
-  stat?: string;            // Stat to modify
-  value?: number;           // Multiplier or bonus value
-  specialId?: string;       // Special effect identifier
-  specialDesc?: string;     // Description of special effect
-}
-
-// Skill evolution system - 5-Tier Continuous Talent Tree
-// Each skill with max level 10 follows this structure:
-// - 5 Tiers (T1-T5)
-// - Each tier has L5 and L10 milestone perk choices
-// - 3 paths per tier (A, B, C columns) representing different playstyles
-// - T3 L10 and T5 L10 have Elite Perks (game-changing mechanics)
-
-export interface SkillEvolutionPath {
-  baseSkillId: string;      // Starting skill ID
-  tiers: SkillTierDef[];    // 5 tiers of evolution
-}
-
-export interface SkillTierDef {
-  tier: number;             // Tier number (1-5)
-  skillId: string;          // Skill ID for this tier
-  name: string;
-  multiplier: number;       // Base effect multiplier for this tier
-  // Perk choices organized by milestone and path (A, B, C)
-  l5Perks: SkillPerkChoice[];   // 3 choices (one per path) at level 5
-  l10Perks: SkillPerkChoice[];  // 3 choices (one per path) at level 10
-}
-
-// Perk choice at a milestone - belongs to a specific path (A, B, or C)
-export interface SkillPerkChoice {
-  id: string;
-  name: string;
-  desc: string;
-  path: 'A' | 'B' | 'C';   // Which path this perk belongs to
-  isElite?: boolean;        // True for T3 L10 and T5 L10 perks
-  effect: SkillUpgradeEffect;
-  // For path compounding - if player stays on same path, bonuses compound
-  pathCompoundBonus?: number; // Exponential bonus for staying on same path
-}
-
-export interface SkillUpgradeChoice {
-  id: string;
-  name: string;
-  desc: string;
-  milestone: 5 | 10;        // Level at which this upgrade is available
-  effect: SkillUpgradeEffect;
-}
-
-export interface PrestigeDef {
-  name: string;
-  desc: string;
-  max: number;
-  cost: number;
-}
-
-// Legacy EquipmentDef for backward compatibility
-export interface EquipmentDef {
-  id: string;
-  name: string;
-  slot: 'mainHand' | 'offHand' | 'head' | 'body' | 'hands' | 'accessory';
-  rarity: 'common' | 'uncommon' | 'rare' | 'epic' | 'legendary' | 'mythic';
-  stats: Record<string, number>;
-  durability: number;
-  maxDurability: number;
-  element?: string;
-}
-
-// Equipment Instance (actual equipped item with enchantments)
-export interface EquipmentInstance {
-  instanceId: string;          // Unique ID for this specific item
-  typeId: string;              // Reference to EquipmentType (e.g., 'basicStaff')
-  name: string;                // Display name (defaults to type name)
-  enchantments: AppliedEnchantment[];
-  usedCapacity: number;        // Currently used capacity
-  totalCapacity: number;       // Base capacity + bonuses
-  rarity: 'common' | 'uncommon' | 'rare' | 'epic' | 'legendary' | 'mythic';
-  quality: number;             // 0-100, affects capacity efficiency
-  weaponMana?: number;         // Current mana stored in weapon (for weapon enchantments)
-  weaponManaMax?: number;      // Max mana the weapon can store
-  weaponManaRegen?: number;    // Mana regen per hour for weapon
-  weaponManaType?: string;     // Type of mana the weapon stores
-  activeWeaponEnchant?: string; // Active weapon enchantment (for magic swords)
-}
-
-export interface AppliedEnchantment {
-  effectId: string;            // Reference to EnchantmentEffectDef
-  stacks: number;              // Number of times this effect is applied
-  actualCost: number;          // Actual capacity cost (after efficiency)
-}
-
-// Enchantment Design (saved design for later application)
-export interface EnchantmentDesign {
-  id: string;
-  name: string;
-  equipmentType: string;       // Which equipment type this is designed for
-  effects: DesignEffect[];
-  totalCapacityUsed: number;
-  designTime: number;          // Hours required to design
-  created: number;             // Timestamp
-}
-
-export interface DesignEffect {
-  effectId: string;
-  stacks: number;
-  capacityCost: number;
-}
-
-// Crafting Progress States
-export interface DesignProgress {
-  designId: string;
-  progress: number;            // Hours spent designing
-  required: number;            // Total hours needed
-  // Design data stored during progress
-  name: string;
-  equipmentType: string;
-  effects: DesignEffect[];
-}
-
-export interface PreparationProgress {
-  equipmentInstanceId: string;
-  progress: number;            // Hours spent preparing
-  required: number;            // Total hours needed
-  manaCostPaid: number;        // Mana cost already paid
-}
-
-export interface ApplicationProgress {
-  equipmentInstanceId: string;
-  designId: string;
-  progress: number;            // Hours spent applying
-  required: number;            // Total hours needed
-  manaPerHour: number;         // Mana cost per hour
-  paused: boolean;
-  manaSpent: number;           // Total mana spent so far
-}
-
-// Equipment crafting progress (from blueprints)
-export interface EquipmentCraftingProgress {
-  blueprintId: string;
-  equipmentTypeId: string;
-  progress: number;            // Hours spent crafting
-  required: number;            // Total hours needed
-  manaSpent: number;           // Total mana spent so far
-}
-
-// Equipment spell state (for multi-spell casting)
-export interface EquipmentSpellState {
-  spellId: string;
-  sourceEquipment: string;     // Equipment instance ID
-  castProgress: number;        // 0-1 progress toward next cast
-}
-
-export interface BlueprintDef {
-  id: string;
-  name: string;
-  tier: number;
-  slot: string;
-  stats: Record<string, number>;
-  studyTime: number;
-  craftTime: number;
-  craftCost: number;
-  discovered: boolean;
-  learned: boolean;
-}
-
-// Loot inventory for materials and blueprints
-export interface LootInventory {
-  materials: Record<string, number>;  // materialId -> count
-  blueprints: string[];               // blueprint IDs discovered
-}
-
-// Achievement definitions
-export interface AchievementDef {
-  id: string;
-  name: string;
-  desc: string;
-  category: string;
-  requirement: {
-    type: string;
-    value: number;
-    subType?: string;
-  };
-  reward: {
-    insight?: number;
-    manaBonus?: number;
-    damageBonus?: number;
-    regenBonus?: number;
-    title?: string;
-    unlockEffect?: string;
-  };
-  hidden?: boolean;
-}
-
-// Achievement state tracks unlocked achievements and progress
-export interface AchievementState {
-  unlocked: string[];              // IDs of unlocked achievements
-  progress: Record<string, number>; // Progress toward achievement requirements
-}
-
-export type GameAction = 'meditate' | 'climb' | 'study' | 'craft' | 'repair' | 'convert' | 'design' | 'prepare' | 'enchant';
-
-export interface ScheduleBlock {
-  id: string;
-  action: GameAction;
-  startHour: number;
-  endHour: number;
-  enabled: boolean;
-  target?: string;          // spell id, blueprint id, skill id, element id
-}
-
-export interface StudyTarget {
-  type: 'skill' | 'spell' | 'blueprint';
-  id: string;
-  progress: number;         // Hours studied
-  required: number;         // Total hours needed
-}
-
-// ─── Golemancy Types ───────────────────────────────────────────────────────────
-
-export interface SummonedGolem {
-  golemId: string;          // Reference to GOLEMS_DEF
-  summonedFloor: number;    // Floor when golem was summoned
-  attackProgress: number;   // Progress toward next attack (0-1)
-}
-
-export interface GolemancyState {
-  enabledGolems: string[];      // Golem IDs the player wants active
-  summonedGolems: SummonedGolem[]; // Currently summoned golems on this floor
-  lastSummonFloor: number;      // Floor golems were last summoned on
-}
-
-export interface GameState {
-  // Time
-  day: number;
-  hour: number;
-  loopCount: number;
-  gameOver: boolean;
-  victory: boolean;
-  paused: boolean;
-
-  // Raw Mana
-  rawMana: number;
-  meditateTicks: number;
-  totalManaGathered: number;
-
-  // Attunements (class-like system)
-  attunements: Record<string, AttunementState>;  // attunement id -> state
-
-  // Elements
-  elements: Record<string, ElementState>;
-
-  // Spire
-  currentFloor: number;
-  floorHP: number;
-  floorMaxHP: number;
-  maxFloorReached: number;
-  signedPacts: number[];
-  activeSpell: string;
-  currentAction: GameAction;
-  castProgress: number;      // Progress towards next spell cast (0-1)
-  
-  // Room system for special floors
-  currentRoom: FloorState;   // Current room state (swarm, puzzle, speed, etc.)
-
-  // Spells
-  spells: Record<string, SpellState>;
-
-  // Skills
-  skills: Record<string, number>;
-  skillProgress: Record<string, number>;  // Saved study progress for skills
-  skillUpgrades: Record<string, string[]>; // Selected upgrade IDs per skill
-  skillTiers: Record<string, number>;      // Current tier for each base skill
-
-  // Equipment System (new instance-based system)
-  equippedInstances: Record<string, string | null>;  // slot -> instanceId
-  equipmentInstances: Record<string, EquipmentInstance>;  // instanceId -> instance
-  enchantmentDesigns: EnchantmentDesign[];  // Saved enchantment designs
-  
-  // Crafting Progress
-  designProgress: DesignProgress | null;
-  preparationProgress: PreparationProgress | null;
-  applicationProgress: ApplicationProgress | null;
-  equipmentCraftingProgress: EquipmentCraftingProgress | null;
-
-  // Unlocked enchantment effects for designing
-  unlockedEffects: string[];  // Effect IDs that have been researched
-
-  // Equipment spell states for multi-casting
-  equipmentSpellStates: EquipmentSpellState[];
-
-  // Legacy Equipment (for backward compatibility)
-  equipment: Record<string, EquipmentDef | null>;
-  inventory: EquipmentDef[];
-
-  // Blueprints
-  blueprints: Record<string, BlueprintDef>;
-
-  // Loot Inventory
-  lootInventory: LootInventory;
-
-  // Schedule
-  schedule: ScheduleBlock[];
-  autoSchedule: boolean;
-  studyQueue: string[];
-  craftQueue: string[];
-
-  // Current Study Target
-  currentStudyTarget: StudyTarget | null;
-  
-  // Parallel Study Target (for Parallel Mind milestone upgrade)
-  parallelStudyTarget: StudyTarget | null;
-
-  // Golemancy (summoned golems)
-  golemancy: GolemancyState;
-
-  // Achievements
-  achievements: AchievementState;
-
-  // Stats tracking
-  totalSpellsCast: number;
-  totalDamageDealt: number;
-  totalCraftsCompleted: number;
-
-  // Prestige
-  insight: number;
-  totalInsight: number;
-  prestigeUpgrades: Record<string, number>;
-  memorySlots: number;
-  memories: string[];
-
-  // Incursion
-  incursionStrength: number;
-  containmentWards: number;
-
-  // Log
-  log: string[];
-
-  // Loop insight (earned at end of current loop)
-  loopInsight: number;
-}
-
-// Action types for the store
-export type GameActionType =
-  | { type: 'TICK' }
-  | { type: 'GATHER_MANA' }
-  | { type: 'SET_ACTION'; action: GameAction }
-  | { type: 'SET_SPELL'; spellId: string }
-  | { type: 'LEARN_SPELL'; spellId: string }
-  | { type: 'START_STUDYING_SKILL'; skillId: string }
-  | { type: 'START_STUDYING_SPELL'; spellId: string }
-  | { type: 'CANCEL_STUDY' }
-  | { type: 'CONVERT_MANA'; element: string; amount: number }
-  | { type: 'UNLOCK_ELEMENT'; element: string }
-  | { type: 'CRAFT_COMPOSITE'; target: string }
-  | { type: 'DO_PRESTIGE'; id: string }
-  | { type: 'START_NEW_LOOP' }
-  | { type: 'TOGGLE_PAUSE' }
-  | { type: 'RESET_GAME' }
-  | { type: 'SELECT_SKILL_UPGRADE'; skillId: string; upgradeId: string }
-  | { type: 'TIER_UP_SKILL'; skillId: string };
+// This file now re-exports types from domain-specific files in the types/ directory.
+// All type definitions have been moved to:
+//   - types/elements.ts - element-related types
+//   - types/attunements.ts - attunement-related types  
+//   - types/spells.ts - spell-related types
+//   - types/skills.ts - skill-related types
+//   - types/equipment.ts - equipment-related types
+//   - types/game.ts - core game state types
+// 
+// Import from this file (types.ts) to maintain backward compatibility,
+// or import directly from the domain-specific files.
+
+export * from './types/index';
diff --git a/src/lib/game/types/attunements.ts b/src/lib/game/types/attunements.ts
new file mode 100644
index 0000000..aabc992
--- /dev/null
+++ b/src/lib/game/types/attunements.ts
@@ -0,0 +1,51 @@
+// ─── Attunement Types ───────────────────────────────────────────────────────
+
+// Attunement body slots
+export type AttunementSlot = 'rightHand' | 'leftHand' | 'head' | 'back' | 'chest' | 'leftLeg' | 'rightLeg';
+
+// Attunement definition
+export interface AttunementDef {
+  id: string;
+  name: string;
+  desc: string;
+  slot: AttunementSlot;
+  icon: string;
+  color: string;
+  primaryManaType?: string;      // Primary mana type this attunement generates (null for Invoker)
+  rawManaRegen: number;          // Raw mana regeneration per hour granted by this attunement
+  conversionRate: number;        // Raw mana converted to primary type per hour
+  unlocked: boolean;             // Whether this is unlocked by default
+  unlockCondition?: string;      // Description of how to unlock (for future challenges)
+  capabilities: string[];        // What this attunement enables (e.g., 'enchanting', 'pacts', 'golemCrafting')
+  skillCategories: string[];     // Skill categories this attunement provides access to
+}
+
+// Attunement instance state (tracks player's attunements)
+export interface AttunementState {
+  id: string;
+  active: boolean;               // Whether this attunement is currently active
+  level: number;                 // Attunement level (for future progression)
+  experience: number;            // Progress toward next level
+}
+
+// Boon types that guardians can grant
+export interface GuardianBoon {
+  type: 'maxMana' | 'manaRegen' | 'castingSpeed' | 'elementalDamage' | 'rawDamage' | 
+        'critChance' | 'critDamage' | 'spellEfficiency' | 'manaGain' | 'insightGain' | 
+        'studySpeed' | 'prestigeInsight';
+  value: number;
+  desc: string;
+}
+
+export interface GuardianDef {
+  name: string;
+  element: string;
+  hp: number;
+  pact: number;           // Pact multiplier when signed
+  color: string;
+  boons: GuardianBoon[];  // Bonuses granted when pact is signed
+  pactCost: number;       // Mana cost to perform pact ritual
+  pactTime: number;       // Hours required for pact ritual
+  uniquePerk: string;     // Description of unique perk
+  armor?: number;         // Damage reduction (0-1, e.g., 0.2 = 20% reduction)
+}
diff --git a/src/lib/game/types/elements.ts b/src/lib/game/types/elements.ts
new file mode 100644
index 0000000..ba917a8
--- /dev/null
+++ b/src/lib/game/types/elements.ts
@@ -0,0 +1,18 @@
+// ─── Element Types ───────────────────────────────────────────────────────────
+
+export type ElementCategory = 'base' | 'utility' | 'composite' | 'exotic';
+
+export interface ElementDef {
+  name: string;
+  sym: string;
+  color: string;
+  glow: string;
+  cat: ElementCategory;
+  recipe?: string[];
+}
+
+export interface ElementState {
+  current: number;
+  max: number;
+  unlocked: boolean;
+}
diff --git a/src/lib/game/types/equipment.ts b/src/lib/game/types/equipment.ts
new file mode 100644
index 0000000..b9edae5
--- /dev/null
+++ b/src/lib/game/types/equipment.ts
@@ -0,0 +1,116 @@
+// ─── Equipment Types ───────────────────────────────────────────────────────
+
+// Legacy EquipmentDef for backward compatibility
+export interface EquipmentDef {
+  id: string;
+  name: string;
+  slot: 'mainHand' | 'offHand' | 'head' | 'body' | 'hands' | 'accessory';
+  rarity: 'common' | 'uncommon' | 'rare' | 'epic' | 'legendary' | 'mythic';
+  stats: Record<string, number>;
+  durability: number;
+  maxDurability: number;
+  element?: string;
+}
+
+// Equipment Instance (actual equipped item with enchantments)
+export interface EquipmentInstance {
+  instanceId: string;          // Unique ID for this specific item
+  typeId: string;              // Reference to EquipmentType (e.g., 'basicStaff')
+  name: string;                // Display name (defaults to type name)
+  enchantments: AppliedEnchantment[];
+  usedCapacity: number;        // Currently used capacity
+  totalCapacity: number;       // Base capacity + bonuses
+  rarity: 'common' | 'uncommon' | 'rare' | 'epic' | 'legendary' | 'mythic';
+  quality: number;             // 0-100, affects capacity efficiency
+  weaponMana?: number;         // Current mana stored in weapon (for weapon enchantments)
+  weaponManaMax?: number;      // Max mana the weapon can store
+  weaponManaRegen?: number;    // Mana regen per hour for weapon
+  weaponManaType?: string;     // Type of mana the weapon stores
+  activeWeaponEnchant?: string; // Active weapon enchantment (for magic swords)
+}
+
+export interface AppliedEnchantment {
+  effectId: string;            // Reference to EnchantmentEffectDef
+  stacks: number;              // Number of times this effect is applied
+  actualCost: number;          // Actual capacity cost (after efficiency)
+}
+
+// Enchantment Design (saved design for later application)
+export interface EnchantmentDesign {
+  id: string;
+  name: string;
+  equipmentType: string;       // Which equipment type this is designed for
+  effects: DesignEffect[];
+  totalCapacityUsed: number;
+  designTime: number;          // Hours required to design
+  created: number;             // Timestamp
+}
+
+export interface DesignEffect {
+  effectId: string;
+  stacks: number;
+  capacityCost: number;
+}
+
+// Crafting Progress States
+export interface DesignProgress {
+  designId: string;
+  progress: number;            // Hours spent designing
+  required: number;            // Total hours needed
+  // Design data stored during progress
+  name: string;
+  equipmentType: string;
+  effects: DesignEffect[];
+}
+
+export interface PreparationProgress {
+  equipmentInstanceId: string;
+  progress: number;            // Hours spent preparing
+  required: number;            // Total hours needed
+  manaCostPaid: number;        // Mana cost already paid
+}
+
+export interface ApplicationProgress {
+  equipmentInstanceId: string;
+  designId: string;
+  progress: number;            // Hours spent applying
+  required: number;            // Total hours needed
+  manaPerHour: number;         // Mana cost per hour
+  paused: boolean;
+  manaSpent: number;           // Total mana spent so far
+}
+
+// Equipment crafting progress (from blueprints)
+export interface EquipmentCraftingProgress {
+  blueprintId: string;
+  equipmentTypeId: string;
+  progress: number;            // Hours spent crafting
+  required: number;            // Total hours needed
+  manaSpent: number;           // Total mana spent so far
+}
+
+// Equipment spell state (for multi-spell casting)
+export interface EquipmentSpellState {
+  spellId: string;
+  sourceEquipment: string;     // Equipment instance ID
+  castProgress: number;        // 0-1 progress toward next cast
+}
+
+export interface BlueprintDef {
+  id: string;
+  name: string;
+  tier: number;
+  slot: string;
+  stats: Record<string, number>;
+  studyTime: number;
+  craftTime: number;
+  craftCost: number;
+  discovered: boolean;
+  learned: boolean;
+}
+
+// Loot inventory for materials and blueprints
+export interface LootInventory {
+  materials: Record<string, number>;  // materialId -> count
+  blueprints: string[];               // blueprint IDs discovered
+}
diff --git a/src/lib/game/types/game.ts b/src/lib/game/types/game.ts
new file mode 100644
index 0000000..8fa16fe
--- /dev/null
+++ b/src/lib/game/types/game.ts
@@ -0,0 +1,224 @@
+// ─── Core Game State Types ───────────────────────────────────────────────
+
+import type { AttunementState } from './attunements';
+import type { ElementState } from './elements';
+import type { SpellState } from './spells';
+import type { EquipmentInstance, EnchantmentDesign, DesignProgress, PreparationProgress, ApplicationProgress, EquipmentCraftingProgress, EquipmentDef, BlueprintDef, LootInventory, EquipmentSpellState } from './equipment';
+
+// ─── Room and Enemy Types ─────────────────────────────────────────────────────
+
+export type RoomType = 'combat' | 'puzzle' | 'swarm' | 'speed' | 'guardian';
+
+export interface EnemyState {
+  id: string;
+  hp: number;
+  maxHP: number;
+  armor: number;            // Damage reduction (0-1)
+  dodgeChance: number;      // For speed rooms (0-1)
+  element: string;
+}
+
+export interface FloorState {
+  roomType: RoomType;
+  enemies: EnemyState[];      // For swarm rooms, multiple enemies
+  puzzleProgress?: number;    // For puzzle rooms (0-1)
+  puzzleRequired?: number;    // Total progress needed
+  puzzleId?: string;          // Which puzzle type
+  puzzleAttunements?: string[]; // Which attunements speed up this puzzle
+}
+
+// ─── Achievement Types ─────────────────────────────────────────────────────
+
+export interface AchievementDef {
+  id: string;
+  name: string;
+  desc: string;
+  category: string;
+  requirement: {
+    type: string;
+    value: number;
+    subType?: string;
+  };
+  reward: {
+    insight?: number;
+    manaBonus?: number;
+    damageBonus?: number;
+    regenBonus?: number;
+    title?: string;
+    unlockEffect?: string;
+  };
+  hidden?: boolean;
+}
+
+// Achievement state tracks unlocked achievements and progress
+export interface AchievementState {
+  unlocked: string[];              // IDs of unlocked achievements
+  progress: Record<string, number>; // Progress toward achievement requirements
+}
+
+// ─── Game Actions and Scheduling ─────────────────────────────────────────
+
+export type GameAction = 'meditate' | 'climb' | 'study' | 'craft' | 'repair' | 'convert' | 'design' | 'prepare' | 'enchant';
+
+export interface ScheduleBlock {
+  id: string;
+  action: GameAction;
+  startHour: number;
+  endHour: number;
+  enabled: boolean;
+  target?: string;          // spell id, blueprint id, skill id, element id
+}
+
+export interface StudyTarget {
+  type: 'skill' | 'spell' | 'blueprint';
+  id: string;
+  progress: number;         // Hours studied
+  required: number;         // Total hours needed
+}
+
+// ─── Golemancy Types ─────────────────────────────────────────────────────────
+
+export interface SummonedGolem {
+  golemId: string;          // Reference to GOLEMS_DEF
+  summonedFloor: number;    // Floor when golem was summoned
+  attackProgress: number;   // Progress toward next attack (0-1)
+}
+
+export interface GolemancyState {
+  enabledGolems: string[];      // Golem IDs the player wants active
+  summonedGolems: SummonedGolem[]; // Currently summoned golems on this floor
+  lastSummonFloor: number;      // Floor golems were last summoned on
+}
+
+// ─── Main Game State ─────────────────────────────────────────────────────
+
+export interface GameState {
+  // Time
+  day: number;
+  hour: number;
+  loopCount: number;
+  gameOver: boolean;
+  victory: boolean;
+  paused: boolean;
+
+  // Raw Mana
+  rawMana: number;
+  meditateTicks: number;
+  totalManaGathered: number;
+
+  // Attunements (class-like system)
+  attunements: Record<string, AttunementState>;  // attunement id -> state
+
+  // Elements
+  elements: Record<string, ElementState>;
+
+  // Spire
+  currentFloor: number;
+  floorHP: number;
+  floorMaxHP: number;
+  maxFloorReached: number;
+  signedPacts: number[];
+  activeSpell: string;
+  currentAction: GameAction;
+  castProgress: number;      // Progress towards next spell cast (0-1)
+  
+  // Room system for special floors
+  currentRoom: FloorState;   // Current room state (swarm, puzzle, speed, etc.)
+
+  // Spells
+  spells: Record<string, SpellState>;
+
+  // Skills
+  skills: Record<string, number>;
+  skillProgress: Record<string, number>;  // Saved study progress for skills
+  skillUpgrades: Record<string, string[]>; // Selected upgrade IDs per skill
+  skillTiers: Record<string, number>;      // Current tier for each base skill
+
+  // Equipment System (new instance-based system)
+  equippedInstances: Record<string, string | null>;  // slot -> instanceId
+  equipmentInstances: Record<string, EquipmentInstance>;  // instanceId -> instance
+  enchantmentDesigns: EnchantmentDesign[];  // Saved enchantment designs
+  
+  // Crafting Progress
+  designProgress: DesignProgress | null;
+  preparationProgress: PreparationProgress | null;
+  applicationProgress: ApplicationProgress | null;
+  equipmentCraftingProgress: EquipmentCraftingProgress | null;
+
+  // Unlocked enchantment effects for designing
+  unlockedEffects: string[];  // Effect IDs that have been researched
+
+  // Equipment spell states for multi-casting
+  equipmentSpellStates: EquipmentSpellState[];
+
+  // Legacy Equipment (for backward compatibility)
+  equipment: Record<string, EquipmentDef | null>;
+  inventory: EquipmentDef[];
+
+  // Blueprints
+  blueprints: Record<string, BlueprintDef>;
+
+  // Loot Inventory
+  lootInventory: LootInventory;
+
+  // Schedule
+  schedule: ScheduleBlock[];
+  autoSchedule: boolean;
+  studyQueue: string[];
+  craftQueue: string[];
+
+  // Current Study Target
+  currentStudyTarget: StudyTarget | null;
+  
+  // Parallel Study Target (for Parallel Mind milestone upgrade)
+  parallelStudyTarget: StudyTarget | null;
+
+  // Golemancy (summoned golems)
+  golemancy: GolemancyState;
+
+  // Achievements
+  achievements: AchievementState;
+
+  // Stats tracking
+  totalSpellsCast: number;
+  totalDamageDealt: number;
+  totalCraftsCompleted: number;
+
+  // Prestige
+  insight: number;
+  totalInsight: number;
+  prestigeUpgrades: Record<string, number>;
+  memorySlots: number;
+  memories: string[];
+
+  // Incursion
+  incursionStrength: number;
+  containmentWards: number;
+
+  // Log
+  log: string[];
+
+  // Loop insight (earned at end of current loop)
+  loopInsight: number;
+}
+
+// ─── Action Types for Store ─────────────────────────────────────────────
+
+export type GameActionType =
+  | { type: 'TICK' }
+  | { type: 'GATHER_MANA' }
+  | { type: 'SET_ACTION'; action: GameAction }
+  | { type: 'SET_SPELL'; spellId: string }
+  | { type: 'LEARN_SPELL'; spellId: string }
+  | { type: 'START_STUDYING_SKILL'; skillId: string }
+  | { type: 'START_STUDYING_SPELL'; spellId: string }
+  | { type: 'CANCEL_STUDY' }
+  | { type: 'CONVERT_MANA'; element: string; amount: number }
+  | { type: 'UNLOCK_ELEMENT'; element: string }
+  | { type: 'CRAFT_COMPOSITE'; target: string }
+  | { type: 'DO_PRESTIGE'; id: string }
+  | { type: 'START_NEW_LOOP' }
+  | { type: 'TOGGLE_PAUSE' }
+  | { type: 'RESET_GAME' }
+  | { type: 'SELECT_SKILL_UPGRADE'; skillId: string; upgradeId: string }
+  | { type: 'TIER_UP_SKILL'; skillId: string };
diff --git a/src/lib/game/types/index.ts b/src/lib/game/types/index.ts
new file mode 100644
index 0000000..4261a1f
--- /dev/null
+++ b/src/lib/game/types/index.ts
@@ -0,0 +1,56 @@
+// ─── Game Types Index ──────────────────────────────────────────────────────
+
+// Re-export all types from domain-specific files
+
+// Element types
+export type { ElementCategory, ElementDef, ElementState } from './elements';
+
+// Attunement types
+export type { AttunementSlot, AttunementDef, AttunementState, GuardianBoon, GuardianDef } from './attunements';
+
+// Spell types
+export type { SpellCost, SpellDef, SpellEffect, SpellState } from './spells';
+
+// Skill types
+export type { 
+  SkillDef, 
+  SkillUpgradeDef, 
+  SkillUpgradeEffect, 
+  SkillEvolutionPath, 
+  SkillTierDef, 
+  SkillPerkChoice, 
+  SkillUpgradeChoice,
+  PrestigeDef 
+} from './skills';
+
+// Equipment types
+export type { 
+  EquipmentDef, 
+  EquipmentInstance, 
+  AppliedEnchantment, 
+  EnchantmentDesign, 
+  DesignEffect, 
+  DesignProgress, 
+  PreparationProgress, 
+  ApplicationProgress, 
+  EquipmentCraftingProgress, 
+  EquipmentSpellState, 
+  BlueprintDef, 
+  LootInventory 
+} from './equipment';
+
+// Game state types
+export type { 
+  RoomType, 
+  EnemyState, 
+  FloorState, 
+  AchievementDef, 
+  AchievementState, 
+  GameAction, 
+  ScheduleBlock, 
+  StudyTarget, 
+  SummonedGolem, 
+  GolemancyState, 
+  GameState, 
+  GameActionType 
+} from './game';
diff --git a/src/lib/game/types/skills.ts b/src/lib/game/types/skills.ts
new file mode 100644
index 0000000..f736d04
--- /dev/null
+++ b/src/lib/game/types/skills.ts
@@ -0,0 +1,85 @@
+// ─── Skill Types ───────────────────────────────────────────────────────────
+
+export interface SkillDef {
+  name: string;
+  desc: string;
+  cat: string;
+  attunement?: string;  // Which attunement this skill belongs to (null = core)
+  max: number;
+  base: number;             // Mana cost to start studying
+  req?: Record<string, number>;  // Skill prerequisites
+  attunementReq?: Record<string, number>;  // Attunement level requirements (attunement id -> min level)
+  studyTime: number;        // Hours needed to study
+  level?: number;           // Current level (optional, for UI display)
+  tier?: number;            // Skill tier (1-5)
+  tierUp?: string;          // Skill ID this evolves into at max level
+  baseSkill?: string;       // Original skill ID this evolved from
+  tierMultiplier?: number;  // Multiplier for each tier (default 2)
+}
+
+// Skill upgrade choices at milestones (level 5 and level 10)
+export interface SkillUpgradeDef {
+  id: string;
+  name: string;
+  desc: string;
+  skillId: string;          // Which skill this upgrade belongs to
+  milestone: 5 | 10;        // Level at which this upgrade is available
+  effect: SkillUpgradeEffect;
+}
+
+export interface SkillUpgradeEffect {
+  type: 'multiplier' | 'bonus' | 'special';
+  stat?: string;            // Stat to modify
+  value?: number;           // Multiplier or bonus value
+  specialId?: string;       // Special effect identifier
+  specialDesc?: string;     // Description of special effect
+}
+
+// Skill evolution system - 5-Tier Continuous Talent Tree
+// Each skill with max level 10 follows this structure:
+// - 5 Tiers (T1-T5)
+// - Each tier has L5 and L10 milestone perk choices
+// - 3 paths per tier (A, B, C columns) representing different playstyles
+// - T3 L10 and T5 L10 have Elite Perks (game-changing mechanics)
+
+export interface SkillEvolutionPath {
+  baseSkillId: string;      // Starting skill ID
+  tiers: SkillTierDef[];    // 5 tiers of evolution
+}
+
+export interface SkillTierDef {
+  tier: number;             // Tier number (1-5)
+  skillId: string;          // Skill ID for this tier
+  name: string;
+  multiplier: number;       // Base effect multiplier for this tier
+  // Perk choices organized by milestone and path (A, B, C)
+  l5Perks: SkillPerkChoice[];   // 3 choices (one per path) at level 5
+  l10Perks: SkillPerkChoice[];  // 3 choices (one per path) at level 10
+}
+
+// Perk choice at a milestone - belongs to a specific path (A, B, or C)
+export interface SkillPerkChoice {
+  id: string;
+  name: string;
+  desc: string;
+  path: 'A' | 'B' | 'C';   // Which path this perk belongs to
+  isElite?: boolean;        // True for T3 L10 and T5 L10 perks
+  effect: SkillUpgradeEffect;
+  // For path compounding - if player stays on same path, bonuses compound
+  pathCompoundBonus?: number; // Exponential bonus for staying on same path
+}
+
+export interface SkillUpgradeChoice {
+  id: string;
+  name: string;
+  desc: string;
+  milestone: 5 | 10;        // Level at which this upgrade is available
+  effect: SkillUpgradeEffect;
+}
+
+export interface PrestigeDef {
+  name: string;
+  desc: string;
+  max: number;
+  cost: number;
+}
diff --git a/src/lib/game/types/spells.ts b/src/lib/game/types/spells.ts
new file mode 100644
index 0000000..d7ec35d
--- /dev/null
+++ b/src/lib/game/types/spells.ts
@@ -0,0 +1,38 @@
+// ─── Spell Types ────────────────────────────────────────────────────────────
+
+// Spell cost can be raw mana or elemental mana
+export interface SpellCost {
+  type: 'raw' | 'element';  // 'raw' for raw mana, 'element' for specific elemental mana
+  element?: string;          // Required if type is 'element'
+  amount: number;            // Amount of mana required
+}
+
+export interface SpellDef {
+  name: string;
+  elem: string;              // Element type for damage calculations
+  dmg: number;
+  cost: SpellCost;           // Changed from number to SpellCost object
+  tier: number;
+  unlock: number;            // Mana cost to start studying
+  studyTime?: number;        // Hours needed to study (optional, defaults based on tier)
+  castSpeed?: number;        // Casts per hour (default 1, higher = faster)
+  desc?: string;             // Optional spell description
+  effects?: SpellEffect[];   // Optional special effects
+  isAoe?: boolean;           // AOE spell that hits multiple enemies
+  aoeTargets?: number;       // Number of enemies hit by AOE
+  isWeaponEnchant?: boolean; // Can be used as weapon enchantment (magic swords)
+}
+
+export interface SpellEffect {
+  type: 'burn' | 'freeze' | 'stun' | 'pierce' | 'multicast' | 'shield' | 'buff' | 'chain' | 'aoe' | 'armor_pierce';
+  value: number;            // Effect potency
+  duration?: number;        // Duration in hours for timed effects
+  targets?: number;         // For AOE: number of targets
+  chance?: number;          // For chance-based effects (e.g., stun chance)
+}
+
+export interface SpellState {
+  learned: boolean;
+  level: number;
+  studyProgress?: number;   // Hours studied so far (for in-progress spells)
+}