feat(backend): Integrate Derived Stats into combat, loot, and crafting mechanics

api/database.py

@@ -308,6 +308,16 @@ player_statistics = Table(
 )
 
 
+character_perks = Table(
+    "character_perks",
+    metadata,
+    Column("id", Integer, primary_key=True, autoincrement=True),
+    Column("character_id", Integer, ForeignKey("characters.id", ondelete="CASCADE"), nullable=False),
+    Column("perk_id", String(50), nullable=False),
+    Column("acquired_at", Float, nullable=False),
+    UniqueConstraint("character_id", "perk_id", name="uix_character_perk")
+)
+
 # ========================================================================
 # QUESTS AND TRADE TABLES
 # ========================================================================
@@ -2937,3 +2947,47 @@ async def acknowledge_pvp_combat(combat_id: int, player_id: int) -> bool:
             
         await session.commit()
         return True
+
+
+# ========================================================================
+# CHARACTER PERKS
+# ========================================================================
+
+async def get_character_perks(character_id: int) -> list:
+    """Get all perks owned by a character."""
+    async with DatabaseSession() as session:
+        stmt = select(character_perks).where(
+            character_perks.c.character_id == character_id
+        )
+        result = await session.execute(stmt)
+        return [dict(row._mapping) for row in result.fetchall()]
+
+
+async def add_character_perk(character_id: int, perk_id: str) -> bool:
+    """Add a perk to a character. Returns False if already owned."""
+    import time
+    async with DatabaseSession() as session:
+        try:
+            stmt = insert(character_perks).values(
+                character_id=character_id,
+                perk_id=perk_id,
+                acquired_at=time.time()
+            )
+            await session.execute(stmt)
+            await session.commit()
+            return True
+        except Exception:
+            return False
+
+
+async def remove_character_perk(character_id: int, perk_id: str) -> bool:
+    """Remove a perk from a character."""
+    async with DatabaseSession() as session:
+        stmt = delete(character_perks).where(
+            character_perks.c.character_id == character_id,
+            character_perks.c.perk_id == perk_id
+        )
+        result = await session.execute(stmt)
+        await session.commit()
+        return result.rowcount > 0
+

api/game_logic.py

@@ -208,12 +208,17 @@ async def interact_with_object(
     items_dropped = []
     damage_taken = outcome.damage_taken
     
-    # Calculate current capacity
+    # Calculate current capacity and fetch derived stats
     from api.services.helpers import calculate_player_capacity
+    from api.services.stats import calculate_derived_stats
     from api.items import items_manager as ITEMS_MANAGER
+    
     inventory = await db.get_inventory(player_id)
     current_weight, max_weight, current_volume, max_volume = await calculate_player_capacity(inventory, ITEMS_MANAGER)
     
+    stats = await calculate_derived_stats(player_id)
+    loot_quality = stats.get('loot_quality', 1.0)
+    
     # Add items to inventory (or drop if over capacity)
     for item_id, quantity in outcome.items_reward.items():
         item = items_manager.get_item(item_id)
@@ -258,7 +263,12 @@ async def interact_with_object(
                     await db.drop_item_to_world(item_id, 1, player['location_id'], unique_item_id=unique_item_id)
                     items_dropped.append(f"{emoji} {item_name}")
         else:
-            # Stackable items - process as before
+            # Stackable items - apply loot quality bonus for resources and consumables
+            if getattr(item, 'category', item.type) in ['resource', 'consumable'] and loot_quality > 1.0:
+                bonus_chance = loot_quality - 1.0
+                if random.random() < bonus_chance:
+                    quantity += 1
+                    
             item_weight = item.weight * quantity
             item_volume = item.volume * quantity
             
@@ -312,6 +322,15 @@ async def use_item(player_id: int, item_id: str, items_manager, locale: str = 'e
     if not player:
         return {"success": False, "message": "Player not found"}
     
+    # Get derived stats for item effectiveness
+    # In some paths redis_manager might not be injected, so we attempt to fetch it from websockets module if needed,
+    # or let stats service fetch without cache
+    from api.services.stats import calculate_derived_stats
+    import api.core.websockets as ws
+    redis_mgr = getattr(ws.manager, 'redis_manager', None)
+    stats = await calculate_derived_stats(player['id'], redis_mgr)
+    item_effectiveness = stats.get('item_effectiveness', 1.0)
+    
     # Check if player has the item
     inventory = await db.get_inventory(player_id)
     item_entry = None
@@ -385,7 +404,8 @@ async def use_item(player_id: int, item_id: str, items_manager, locale: str = 'e
 
     # 3. Direct Healing (Legacy/Instant)
     if 'hp_restore' in item.effects:
-        hp_restore = item.effects['hp_restore']
+        base_hp_restore = item.effects['hp_restore']
+        hp_restore = int(base_hp_restore * item_effectiveness)
         old_hp = player['hp']
         new_hp = min(player['max_hp'], old_hp + hp_restore)
         actual_restored = new_hp - old_hp
@@ -395,7 +415,8 @@ async def use_item(player_id: int, item_id: str, items_manager, locale: str = 'e
             effects_msg.append(f"+{actual_restored} HP")
     
     if 'stamina_restore' in item.effects:
-        stamina_restore = item.effects['stamina_restore']
+        base_stamina_restore = item.effects['stamina_restore']
+        stamina_restore = int(base_stamina_restore * item_effectiveness)
         old_stamina = player['stamina']
         new_stamina = min(player['max_stamina'], old_stamina + stamina_restore)
         actual_restored = new_stamina - old_stamina
@@ -532,6 +553,14 @@ async def check_and_apply_level_up(player_id: int) -> Dict[str, Any]:
             unspent_points=new_unspent_points
         )
         
+        # Invalidate cached derived stats (level affects max_hp, max_stamina, attack_power, etc.)
+        from api.services.stats import invalidate_stats_cache
+        try:
+            from api.core.websockets import manager as ws_manager
+            await invalidate_stats_cache(player_id, getattr(ws_manager, 'redis_manager', None))
+        except Exception:
+            pass
+        
         return {
             "leveled_up": True,
             "new_level": current_level,
@@ -588,7 +617,7 @@ def generate_npc_intent(npc_def, combat_state: dict) -> dict:
     return intent
 
 
-async def npc_attack(player_id: int, combat: dict, npc_def, reduce_armor_func) -> Tuple[List[dict], bool]:
+async def npc_attack(player_id: int, combat: dict, npc_def, reduce_armor_func, player_stats: dict = None) -> Tuple[List[dict], bool]:
     """
     Execute NPC turn based on PREVIOUS intent, then generate NEXT intent.
     Returns: (messages_list, player_defeated)
@@ -603,21 +632,38 @@ async def npc_attack(player_id: int, combat: dict, npc_def, reduce_armor_func) -
     npc_hp = combat['npc_hp']
     npc_max_hp = combat['npc_max_hp']
     npc_status_str = combat.get('npc_status_effects', '')
+    is_stunned = False
     
     if npc_status_str:
-        # Parse status: "bleeding:5:3" (name:dmg:ticks) or multiple "bleeding:5:3|burning:2:2"
+        # Parse status: "bleeding:5:3" (name:dmg:ticks) or "stun:1"
         # Handling multiple effects separated by |
         effects_list = npc_status_str.split('|')
         active_effects = []
         npc_damage_taken = 0
         npc_healing_received = 0
+        is_stunned = False
         
         for effect_str in effects_list:
             if not effect_str: continue
             try:
                 parts = effect_str.split(':')
+                name = parts[0]
+                
+                if name == 'stun' and len(parts) >= 2:
+                    ticks = int(parts[1])
+                    if ticks > 0:
+                        is_stunned = True
+                        messages.append(create_combat_message(
+                            "skill_effect", 
+                            origin="enemy", 
+                            message=f"💫 {npc_def.name} is stunned and cannot act!"
+                        ))
+                        ticks -= 1
+                        if ticks > 0:
+                            active_effects.append(f"stun:{ticks}")
+                    continue
+                
                 if len(parts) >= 3:
-                    name = parts[0]
                     dmg = int(parts[1])
                     ticks = int(parts[2])
                     
@@ -698,7 +744,7 @@ async def npc_attack(player_id: int, combat: dict, npc_def, reduce_armor_func) -
     actual_damage = 0
     
     # EXECUTE INTENT
-    if npc_hp > 0: # Only attack if alive
+    if npc_hp > 0 and not is_stunned: # Only attack if alive and not stunned
         if intent_type == 'defend':
             # NPC defends - heals 5% HP
             heal_amount = int(combat['npc_max_hp'] * 0.05)
@@ -765,28 +811,65 @@ async def npc_attack(player_id: int, combat: dict, npc_def, reduce_armor_func) -
                 # Remove defending effect after use
                 await db.remove_effect(player_id, 'defending')
                 
-            armor_absorbed, broken_armor = await reduce_armor_func(player_id, npc_damage)
-            actual_damage = max(1, npc_damage - armor_absorbed)
-            new_player_hp = max(0, player['hp'] - actual_damage)
-            
-            messages.append(create_combat_message(
-                "enemy_attack", 
-                origin="enemy", 
-                npc_name=npc_def.name, 
-                damage=npc_damage, 
-                armor_absorbed=armor_absorbed
-            ))
-                
-            if broken_armor:
-                for armor in broken_armor:
+            # Check for dodge
+            dodged = False
+            if player_stats and 'dodge_chance' in player_stats:
+                if random.random() < player_stats['dodge_chance']:
+                    dodged = True
                     messages.append(create_combat_message(
-                        "item_broken",
-                        origin="player",
-                        item_name=armor['name'],
-                        emoji=armor['emoji']
+                        "combat_dodge",
+                        origin="player"
                     ))
+                    # Prevent damage calculation
+                    actual_damage = 0
+                    new_player_hp = player['hp']
+
+            # Check for block (if shield is equipped)
+            blocked = False
+            if not dodged and player_stats and player_stats.get('has_shield', False):
+                if random.random() < player_stats.get('block_chance', 0):
+                    blocked = True
+                    messages.append(create_combat_message(
+                        "combat_block",
+                        origin="player"
+                    ))
+                    # Apply blocked effect (damage reduced significantly or nullified)
+                    npc_damage = max(1, int(npc_damage * 0.2)) # Block mitigates 80% damage
                     
-            await db.update_player(player_id, hp=new_player_hp)
+            if not dodged:
+                # Calculate armor durability loss based on PRE-reduction damage
+                armor_absorbed, broken_armor = await reduce_armor_func(player_id, npc_damage)
+                
+                # If player_stats provides a percentage reduction, apply it instead of raw absorption
+                if player_stats and player_stats.get('armor_reduction', 0) > 0:
+                    pct_reduction = player_stats['armor_reduction']
+                    actual_damage = max(1, int(npc_damage * (1 - pct_reduction)))
+                    # Still show "armor_absorbed" conceptually for UI logs, though it's % based now
+                    armor_absorbed_visual = npc_damage - actual_damage
+                else:
+                    actual_damage = max(1, npc_damage - armor_absorbed)
+                    armor_absorbed_visual = armor_absorbed
+                
+                new_player_hp = max(0, player['hp'] - actual_damage)
+                
+                messages.append(create_combat_message(
+                    "enemy_attack", 
+                    origin="enemy", 
+                    npc_name=npc_def.name, 
+                    damage=actual_damage, 
+                    armor_absorbed=armor_absorbed_visual
+                ))
+                
+                if broken_armor and not dodged:
+                    for armor in broken_armor:
+                        messages.append(create_combat_message(
+                            "item_broken",
+                            origin="player",
+                            item_name=armor['name'],
+                            emoji=armor['emoji']
+                        ))
+                    
+                await db.update_player(player_id, hp=new_player_hp)
 
     # GENERATE NEXT INTENT
     

api/items.py

@@ -31,6 +31,8 @@ class Item:
     tier: int = 1  # Item tier (1-5)
     encumbrance: int = 0  # Encumbrance penalty when equipped
     weapon_effects: Dict[str, Any] = None  # Weapon effects: bleeding, stun, etc.
+    weapon_type: str = None  # e.g. 'two_handed', 'one_handed', 'dagger', 'bow'
+    equip_requirements: Dict[str, int] = None  # e.g. {'level': 15, 'strength': 20}
     # Repair system
     repairable: bool = False  # Can this item be repaired?
     repair_materials: list = None  # Materials needed for repair
@@ -72,6 +74,8 @@ class Item:
             self.uncraft_tools = []
         if self.combat_effects is None:
             self.combat_effects = {}
+        if self.equip_requirements is None:
+            self.equip_requirements = {}
 
 
 class ItemsManager:
@@ -139,7 +143,9 @@ class ItemsManager:
                     uncraft_tools=item_data.get('uncraft_tools', []),
                     combat_usable=item_data.get('combat_usable', is_consumable),  # Default: consumables are combat usable
                     combat_only=item_data.get('combat_only', False),
-                    combat_effects=item_data.get('combat_effects', {})
+                    combat_effects=item_data.get('combat_effects', {}),
+                    weapon_type=item_data.get('weapon_type'),
+                    equip_requirements=item_data.get('equip_requirements', {})
                 )
                 self.items[item_id] = item
             

api/main.py

@@ -186,7 +186,7 @@ except Exception as e:
 # Initialize routers with game data dependencies
 game_routes.init_router_dependencies(LOCATIONS, ITEMS_MANAGER, WORLD, redis_manager)
 combat.init_router_dependencies(LOCATIONS, ITEMS_MANAGER, WORLD, redis_manager, QUESTS_DATA)
-equipment.init_router_dependencies(LOCATIONS, ITEMS_MANAGER, WORLD)
+equipment.init_router_dependencies(LOCATIONS, ITEMS_MANAGER, WORLD, redis_manager)
 crafting.init_router_dependencies(LOCATIONS, ITEMS_MANAGER, WORLD)
 loot.init_router_dependencies(LOCATIONS, ITEMS_MANAGER, WORLD)
 statistics.init_router_dependencies(LOCATIONS, ITEMS_MANAGER, WORLD)

api/routers/combat.py

@@ -250,6 +250,10 @@ async def combat_action(
     player = current_user  # current_user is already the character dict
     npc_def = NPCS.get(combat['npc_id'])
     
+    # Get player derived stats
+    from ..services.stats import calculate_derived_stats
+    stats = await calculate_derived_stats(player['id'], redis_manager)
+
     messages = []
     combat_over = False
     
@@ -290,7 +294,7 @@ async def combat_action(
         elif total_impact < 0:
             # HEALING
             heal = abs(total_impact)
-            new_hp = min(player['max_hp'], player['hp'] + heal)
+            new_hp = min(stats['max_hp'], player['hp'] + heal)
             actual_heal = new_hp - player['hp']
             
             if actual_heal > 0:
@@ -307,26 +311,20 @@ async def combat_action(
 
     
     if req.action == 'attack':
-        # Calculate player damage
-        base_damage = 5
-        strength_bonus = player['strength'] // 2
-        level_bonus = player['level']
-        weapon_damage = 0
+        # Calculate player damage using derived stats
+        base_damage = stats.get('attack_power', 5)
         weapon_effects = {}
         weapon_inv_id = None
         
-        # Check for equipped weapon
+        # Check for equipped weapon to apply durability loss and effects
+        # (Attack power from the weapon is already included in stats['attack_power'])
         equipment = await db.get_all_equipment(player['id'])
         if equipment.get('weapon') and equipment['weapon']:
             weapon_slot = equipment['weapon']
             inv_item = await db.get_inventory_item_by_id(weapon_slot['item_id'])
             if inv_item:
                 weapon_def = ITEMS_MANAGER.get_item(inv_item['item_id'])
-                if weapon_def and weapon_def.stats:
-                    weapon_damage = random.randint(
-                        weapon_def.stats.get('damage_min', 0),
-                        weapon_def.stats.get('damage_max', 0)
-                    )
+                if weapon_def:
                     weapon_effects = weapon_def.weapon_effects if hasattr(weapon_def, 'weapon_effects') else {}
                     weapon_inv_id = weapon_slot['item_id']
         
@@ -339,7 +337,7 @@ async def combat_action(
                 attack_failed = True
         
         variance = random.randint(-2, 2)
-        damage = max(1, base_damage + strength_bonus + level_bonus + weapon_damage + variance)
+        damage = max(1, base_damage + variance)
         
         if attack_failed:
             messages.append(create_combat_message(
@@ -349,12 +347,31 @@ async def combat_action(
             ))
             new_npc_hp = combat['npc_hp']
         else:
+            # Check for critical hit
+            is_critical = False
+            crit_chance = stats.get('crit_chance', 0.05)
+            if random.random() < crit_chance:
+                is_critical = True
+                damage = int(damage * stats.get('crit_damage', 1.5))
+                
+            # Apply NPC defense reduction
+            npc_defense = getattr(npc_def, 'defense', 0)
+            actual_damage = max(1, damage - npc_defense)
+            
             # Apply damage to NPC
-            new_npc_hp = max(0, combat['npc_hp'] - damage)
+            new_npc_hp = max(0, combat['npc_hp'] - actual_damage)
+            
+            if is_critical:
+                messages.append(create_combat_message(
+                    "combat_crit",
+                    origin="player"
+                ))
+            
             messages.append(create_combat_message(
                 "player_attack", 
                 origin="player", 
-                damage=damage
+                damage=actual_damage,
+                armor_absorbed=npc_defense if npc_defense > 0 else 0
             ))
             
             # Apply weapon effects
@@ -715,36 +732,278 @@ async def combat_action(
                 await db.update_player_statistics(player['id'], failed_flees=1, damage_taken=npc_damage, increment=True)
                 await db.update_combat(player['id'], {'turn': 'player', 'turn_started_at': time.time()})
     
-    elif req.action == 'defend':
-        # Apply "defending" status effect - reduces incoming damage by 50% for 1 turn
-        await db.add_effect(
-            player_id=player['id'],
-            effect_name='defending',
-            effect_icon='🛡️',
-            effect_type='buff',
-            value=50,  # 50% damage reduction
-            ticks_remaining=1,
-            persist_after_combat=False,
-            source='action:defend'
-        )
+    elif req.action == 'skill':
+        # ── SKILL ACTION ──
+        if not req.skill_id:
+            raise HTTPException(status_code=400, detail="skill_id required for skill action")
         
-        messages.append(create_combat_message(
-            "defend",
-            origin="player",
-            message=get_game_message('defend_text', locale, name=player['name'])
-        ))
+        from ..services.skills import skills_manager
+        skill = skills_manager.get_skill(req.skill_id)
+        if not skill:
+            raise HTTPException(status_code=404, detail="Skill not found")
         
-        # NPC's turn after defend
-        npc_attack_messages, player_defeated = await game_logic.npc_attack(
-            player['id'], 
-            {'npc_hp': combat['npc_hp'], 'npc_max_hp': combat['npc_max_hp']}, 
-            npc_def, 
-            reduce_armor_durability
-        )
-        messages.extend(npc_attack_messages)
-        if player_defeated:
-            await db.remove_non_persistent_effects(player['id'])
+        # Check unlocked
+        stat_val = player.get(skill.stat_requirement, 0)
+        if stat_val < skill.stat_threshold or player['level'] < skill.level_requirement:
+            raise HTTPException(status_code=400, detail="Skill not unlocked")
+        
+        # Check cooldown
+        active_effects = await db.get_player_effects(player['id'])
+        cd_source = f"cd:{skill.id}"
+        for eff in active_effects:
+            if eff.get('source') == cd_source and eff.get('ticks_remaining', 0) > 0:
+                raise HTTPException(status_code=400, detail=f"Skill on cooldown ({eff['ticks_remaining']} turns)")
+        
+        # Check stamina
+        if player['stamina'] < skill.stamina_cost:
+            raise HTTPException(status_code=400, detail="Not enough stamina")
+        
+        # Deduct stamina
+        new_stamina = player['stamina'] - skill.stamina_cost
+        await db.update_player_stamina(player['id'], new_stamina)
+        player['stamina'] = new_stamina
+        
+        # Add cooldown effect
+        if skill.cooldown > 0:
+            await db.add_effect(
+                player_id=player['id'],
+                effect_name=f"{skill.id}_cooldown",
+                effect_icon="⏳",
+                effect_type="cooldown",
+                value=0,
+                ticks_remaining=skill.cooldown,
+                persist_after_combat=False,
+                source=cd_source
+            )
+        
+        # Get weapon info
+        equipment = await db.get_all_equipment(player['id'])
+        weapon_damage = 0
+        inv_item = None
+        weapon_inv_id = None
+        weapon_def = None
+        if equipment.get('weapon') and equipment['weapon']:
+            weapon_slot = equipment['weapon']
+            inv_item = await db.get_inventory_item_by_id(weapon_slot['item_id'])
+            if inv_item:
+                weapon_def = ITEMS_MANAGER.get_item(inv_item['item_id'])
+                if weapon_def and weapon_def.stats:
+                    weapon_damage = random.randint(
+                        weapon_def.stats.get('damage_min', 0),
+                        weapon_def.stats.get('damage_max', 0)
+                    )
+                    weapon_inv_id = inv_item['id']
+        
+        effects = skill.effects
+        new_npc_hp = combat['npc_hp']
+        combat_over = False
+        player_won = False
+        
+        # ── Damage skills ──
+        if 'damage_multiplier' in effects:
+            base_damage = 5
+            strength_bonus = int(player['strength'] * 1.5)
+            level_bonus = player['level']
+            variance = random.randint(-2, 2)
+            raw_damage = max(1, base_damage + strength_bonus + level_bonus + weapon_damage + variance)
+            
+            multiplier = effects['damage_multiplier']
+            
+            # Execute check
+            if 'execute_threshold' in effects:
+                npc_hp_pct = combat['npc_hp'] / combat['npc_max_hp'] if combat['npc_max_hp'] > 0 else 1
+                if npc_hp_pct <= effects['execute_threshold']:
+                    multiplier = effects.get('execute_multiplier', multiplier)
+            
+            # Exploit Weakness check
+            if effects.get('requires_analyzed'):
+                # Check if NPC has been analyzed this combat
+                analyzed = combat.get('npc_status_effects', '') or ''
+                if 'analyzed' not in analyzed:
+                    multiplier = 1.0  # No bonus if not analyzed
+            
+            damage = max(1, int(raw_damage * multiplier))
+            
+            # Guaranteed crit
+            if effects.get('guaranteed_crit'):
+                damage = int(damage * 1.5)
+            
+            # Multi-hit
+            num_hits = effects.get('hits', 1)
+            total_damage = 0
+            
+            for hit in range(num_hits):
+                hit_dmg = damage if hit == 0 else max(1, int(raw_damage * multiplier))
+                
+                # Armor penetration
+                npc_defense = getattr(npc_def, 'defense', 0)
+                if 'armor_penetration' in effects:
+                    npc_defense = int(npc_defense * (1 - effects['armor_penetration']))
+                
+                actual_hit = max(1, hit_dmg - npc_defense)
+                total_damage += actual_hit
+                new_npc_hp = max(0, new_npc_hp - actual_hit)
+            
+            messages.append(create_combat_message(
+                "skill_attack",
+                origin="player",
+                damage=total_damage,
+                skill_name=skill.name,
+                skill_icon=skill.icon,
+                hits=num_hits
+            ))
+            
+            # Lifesteal
+            if 'lifesteal' in effects:
+                heal_amount = int(total_damage * effects['lifesteal'])
+                new_hp = min(player['max_hp'], player['hp'] + heal_amount)
+                if new_hp > player['hp']:
+                    await db.update_player_hp(player['id'], new_hp)
+                    player['hp'] = new_hp
+                    messages.append(create_combat_message(
+                        "skill_heal", origin="player", heal=heal_amount, skill_icon="🩸"
+                    ))
+            
+            # Poison DoT
+            if 'poison_damage' in effects:
+                poison_str = f"poison:{effects['poison_damage']}:{effects['poison_duration']}"
+                existing = combat.get('npc_status_effects', '') or ''
+                if existing:
+                    existing += '|' + poison_str
+                else:
+                    existing = poison_str
+                await db.update_combat(player['id'], {'npc_status_effects': existing})
+                messages.append(create_combat_message(
+                    "skill_effect", origin="player", message=f"🧪 Poisoned! ({effects['poison_damage']} dmg/turn)"
+                ))
+            
+            # Stun chance
+            if 'stun_chance' in effects and random.random() < effects['stun_chance']:
+                messages.append(create_combat_message(
+                    "skill_effect", origin="player", message="💫 Stunned!"
+                ))
+            
+            # Weapon durability
+            if weapon_inv_id and inv_item and inv_item.get('unique_item_id'):
+                new_durability = await db.decrease_unique_item_durability(inv_item['unique_item_id'], 1)
+                if new_durability is None:
+                    messages.append(create_combat_message("weapon_broke", origin="player", item_name=weapon_def.name if weapon_def else "weapon"))
+                    await db.unequip_item(player['id'], 'weapon')
+        
+        # ── Heal skills ──
+        if 'heal_percent' in effects:
+            heal_amount = int(player['max_hp'] * effects['heal_percent'])
+            new_hp = min(player['max_hp'], player['hp'] + heal_amount)
+            actual = new_hp - player['hp']
+            if actual > 0:
+                await db.update_player_hp(player['id'], new_hp)
+                player['hp'] = new_hp
+            messages.append(create_combat_message(
+                "skill_heal", origin="player", heal=actual, skill_name=skill.name, skill_icon=skill.icon
+            ))
+        
+        # ── Stamina restore skills ──
+        if 'stamina_restore_percent' in effects:
+            restore = int(player['max_stamina'] * effects['stamina_restore_percent'])
+            new_stam = min(player['max_stamina'], player['stamina'] + restore)
+            actual = new_stam - player['stamina']
+            if actual > 0:
+                await db.update_player_stamina(player['id'], new_stam)
+                player['stamina'] = new_stam
+            messages.append(create_combat_message(
+                "skill_effect", origin="player", message=f"⚡ +{actual} Stamina"
+            ))
+        
+        # ── Buff skills ──
+        if 'buff' in effects:
+            buff_name_raw = effects['buff']
+            duration = effects.get('buff_duration', 2)
+            value = 0
+            if 'damage_reduction' in effects:
+                value = int(effects['damage_reduction'] * 100)
+            elif 'damage_bonus' in effects:
+                value = int(effects['damage_bonus'] * 100)
+            
+            await db.add_effect(
+                player_id=player['id'],
+                effect_name=buff_name_raw,
+                effect_icon=skill.icon,
+                effect_type='buff',
+                value=value,
+                ticks_remaining=duration,
+                persist_after_combat=False,
+                source=f'skill:{skill.id}'
+            )
+            messages.append(create_combat_message(
+                "skill_buff", origin="player", 
+                skill_name=skill.name, skill_icon=skill.icon, duration=duration
+            ))
+        
+        # ── Analyze skill ──
+        if effects.get('mark_analyzed'):
+            existing = combat.get('npc_status_effects', '') or ''
+            if 'analyzed' not in existing:
+                if existing:
+                    existing += '|analyzed:0:99'
+                else:
+                    existing = 'analyzed:0:99'
+                await db.update_combat(player['id'], {'npc_status_effects': existing})
+            
+            npc_hp_pct = int((combat['npc_hp'] / combat['npc_max_hp']) * 100) if combat['npc_max_hp'] > 0 else 0
+            intent = combat.get('npc_intent', 'attack')
+            messages.append(create_combat_message(
+                "skill_analyze", origin="player",
+                skill_icon=skill.icon,
+                npc_name=npc_def.name,
+                npc_hp_pct=npc_hp_pct,
+                npc_intent=intent
+            ))
+        
+        # Check NPC death
+        if new_npc_hp <= 0:
+            messages.append(create_combat_message("victory", origin="neutral", npc_name=npc_def.name))
             combat_over = True
+            player_won = True
+            
+            # Award XP
+            xp_reward = npc_def.xp_reward
+            current_xp = player['xp'] + xp_reward
+            await db.update_player(player['id'], xp=current_xp)
+            player['xp'] = current_xp
+            
+            messages.append(create_combat_message("xp_gained", origin="neutral", xp=xp_reward))
+            
+            await db.update_player_statistics(player['id'], enemies_killed=1, increment=True)
+            
+            # Level up check
+            level_result = await game_logic.check_and_apply_level_up(player['id'])
+            if level_result['leveled_up']:
+                messages.append(create_combat_message("level_up", origin="neutral", new_level=level_result['new_level']))
+            
+            # Loot
+            loot_items = npc_def.loot if hasattr(npc_def, 'loot') else []
+            generated_loot = []
+            if loot_items:
+                for loot in loot_items:
+                    if random.random() < loot.get('chance', 1.0):
+                        qty = random.randint(loot.get('min', 1), loot.get('max', 1))
+                        # Only append message in combat log, actual items are in corpse
+                        messages.append(create_combat_message("loot", origin="neutral", item_id=loot['item_id'], quantity=qty))
+                        generated_loot.append({"item_id": loot['item_id'], "quantity": qty})
+            
+            # Create corpse
+            import json
+            await db.create_npc_corpse(
+                combat['npc_id'], 
+                combat.get('location_id', player.get('location_id', '')),
+                json.dumps(generated_loot)
+            )
+            
+            await db.remove_non_persistent_effects(player['id'])
+            messages.extend(npc_attack_messages)
+            if player_defeated:
+                await db.remove_non_persistent_effects(player['id'])
+                combat_over = True
     
     elif req.action == 'use_item':
         combat_over = False
@@ -791,9 +1050,10 @@ async def combat_action(
         # 1. Apply Status Effects (e.g. Regeneration from Bandage)
         if item_def.effects.get('status_effect'):
             status_data = item_def.effects['status_effect']
+            status_name = status_data['name']
             await db.add_effect(
                 player_id=player['id'],
-                effect_name=status_data['name'],
+                effect_name=status_name,
                 effect_icon=status_data.get('icon', '✨'),
                 effect_type=status_data.get('type', 'buff'),
                 damage_per_tick=status_data.get('damage_per_tick', 0),
@@ -813,7 +1073,10 @@ async def combat_action(
 
         # 3. Handle Direct healing (legacy/instant)
         if item_def.effects.get('hp_restore') and item_def.effects['hp_restore'] > 0:
-            hp_restore = item_def.effects['hp_restore']
+            item_effectiveness = stats.get('item_effectiveness', 1.0)
+            base_hp_restore = item_def.effects['hp_restore']
+            hp_restore = int(base_hp_restore * item_effectiveness)
+            
             old_hp = player['hp']
             new_hp = min(player.get('max_hp', 100), old_hp + hp_restore)
             actual_restored = new_hp - old_hp
@@ -821,8 +1084,11 @@ async def combat_action(
                 await db.update_player_hp(player['id'], new_hp)
                 effects_applied.append(f"+{actual_restored} HP")
         
-        if item_def.effects.get('stamina_restore'):
-            stamina_restore = item_def.effects['stamina_restore']
+        if item_def.effects.get('stamina_restore') and item_def.effects['stamina_restore'] > 0:
+            item_effectiveness = stats.get('item_effectiveness', 1.0)
+            base_stamina_restore = item_def.effects['stamina_restore']
+            stamina_restore = int(base_stamina_restore * item_effectiveness)
+            
             old_stamina = player['stamina']
             new_stamina = min(player.get('max_stamina', 100), old_stamina + stamina_restore)
             actual_restored = new_stamina - old_stamina
@@ -1259,6 +1525,12 @@ async def pvp_combat_action(
     current_player = attacker if is_attacker else defender
     opponent = defender if is_attacker else attacker
     
+    # Get derived stats for both players
+    from ..services.stats import calculate_derived_stats
+    current_player_stats = await calculate_derived_stats(current_player['id'], redis_manager)
+    # Opponent stats won't be used for attack calculation but could be used for defense logic
+    # opponent_stats = await calculate_derived_stats(opponent['id'], redis_manager)
+
     messages = []
     combat_over = False
     winner_id = None
@@ -1267,24 +1539,18 @@ async def pvp_combat_action(
     last_action_text = ""
     
     if req.action == 'attack':
-        # Calculate damage (similar to PvE)
-        base_damage = 5
-        strength_bonus = current_player['strength'] * 2
-        level_bonus = current_player['level']
+        # Calculate damage (unified formula with derived stats)
+        base_damage = current_player_stats.get('attack_power', 5)
         
-        # Check for equipped weapon
-        weapon_damage = 0
+        # Check for equipped weapon to apply durability loss
+        # (Attack power from the weapon is already included in stats['attack_power'])
         equipment = await db.get_all_equipment(current_player['id'])
         if equipment.get('weapon') and equipment['weapon']:
             weapon_slot = equipment['weapon']
             inv_item = await db.get_inventory_item_by_id(weapon_slot['item_id'])
             if inv_item:
                 weapon_def = ITEMS_MANAGER.get_item(inv_item['item_id'])
-                if weapon_def and weapon_def.stats:
-                    weapon_damage = random.randint(
-                        weapon_def.stats.get('damage_min', 0),
-                        weapon_def.stats.get('damage_max', 0)
-                    )
+                if weapon_def:
                     # Decrease weapon durability
                     if inv_item.get('unique_item_id'):
                         new_durability = await db.decrease_unique_item_durability(inv_item['unique_item_id'], 1)
@@ -1297,17 +1563,31 @@ async def pvp_combat_action(
                             await db.unequip_item(current_player['id'], 'weapon')
         
         variance = random.randint(-2, 2)
-        damage = max(1, base_damage + strength_bonus + level_bonus + weapon_damage + variance)
+        damage = max(1, base_damage + variance)
+        
+        # Check for critical hit
+        is_critical = False
+        crit_chance = current_player_stats.get('crit_chance', 0.05)
+        if random.random() < crit_chance:
+            is_critical = True
+            damage = int(damage * current_player_stats.get('crit_damage', 1.5))
         
         # Apply armor reduction and durability loss to opponent
         armor_absorbed, broken_armor = await reduce_armor_durability(opponent['id'], damage)
         actual_damage = max(1, damage - armor_absorbed)
         
+        if is_critical:
+            messages.append(create_combat_message(
+                "combat_crit",
+                origin="player"
+            ))
+            last_action_text += f"\nCritical Hit! "
+        
         # Structure the attack message
         messages.append(create_combat_message(
             "player_attack",
             origin="player",
-            damage=damage,
+            damage=actual_damage,
             armor_absorbed=armor_absorbed
         ))
         

api/routers/crafting.py

@@ -179,6 +179,11 @@ async def craft_item(request: CraftItemRequest, current_user: dict = Depends(get
         if not player:
             raise HTTPException(status_code=404, detail="Player not found")
         
+        # Get derived stats for crafting bonus
+        from ..services.stats import calculate_derived_stats
+        stats = await calculate_derived_stats(player['id'], redis_manager)
+        crafting_bonus = stats.get('crafting_bonus', 0.0)
+        
         location_id = player['location_id']
         location = LOCATIONS.get(location_id)
         
@@ -287,11 +292,13 @@ async def craft_item(request: CraftItemRequest, current_user: dict = Depends(get
         if hasattr(item_def, 'durability') and item_def.durability:
             # This is a unique item - generate random stats
             base_durability = item_def.durability
-            # Random durability: 90-110% of base
-            random_durability = int(base_durability * random.uniform(0.9, 1.1))
             
-            # Generate tier based on durability roll
-            durability_percent = (random_durability / base_durability)
+            # Random durability: 90-110% of base, plus crafting_bonus (e.g. +0.05 from Intellect)
+            base_roll = random.uniform(0.9, 1.1)
+            durability_percent = base_roll + crafting_bonus
+            random_durability = int(base_durability * durability_percent)
+            
+            # Generate tier based on the final durability percentage
             if durability_percent >= 1.08:
                 tier = 5  # Gold
             elif durability_percent >= 1.04:
@@ -308,8 +315,9 @@ async def craft_item(request: CraftItemRequest, current_user: dict = Depends(get
             if hasattr(item_def, 'stats') and item_def.stats:
                 for stat_key, stat_value in item_def.stats.items():
                     if isinstance(stat_value, (int, float)):
-                        # Random stat: 90-110% of base
-                        random_stats[stat_key] = int(stat_value * random.uniform(0.9, 1.1))
+                        # Random stat: same multiplier logic applied to base stats
+                        stat_percent = random.uniform(0.9, 1.1) + crafting_bonus
+                        random_stats[stat_key] = int(stat_value * stat_percent)
                     else:
                         random_stats[stat_key] = stat_value
             

api/routers/equipment.py

@@ -24,13 +24,15 @@ logger = logging.getLogger(__name__)
 LOCATIONS = None
 ITEMS_MANAGER = None
 WORLD = None
+redis_manager = None
 
-def init_router_dependencies(locations, items_manager, world):
+def init_router_dependencies(locations, items_manager, world, redis_mgr=None):
     """Initialize router with game data dependencies"""
-    global LOCATIONS, ITEMS_MANAGER, WORLD
+    global LOCATIONS, ITEMS_MANAGER, WORLD, redis_manager
     LOCATIONS = locations
     ITEMS_MANAGER = items_manager
     WORLD = world
+    redis_manager = redis_mgr
 
 router = APIRouter(tags=["equipment"])
 
@@ -62,6 +64,25 @@ async def equip_item(
     if not item_def.equippable or not item_def.slot:
         raise HTTPException(status_code=400, detail="This item cannot be equipped")
     
+    # Check equipment requirements (level + stat gates)
+    if item_def.equip_requirements:
+        player = await db.get_player_by_id(player_id) if 'level' not in current_user else current_user
+        
+        req_level = item_def.equip_requirements.get('level', 0)
+        if player.get('level', 1) < req_level:
+            raise HTTPException(
+                status_code=400,
+                detail=get_game_message('equip_level_required', locale, level=req_level)
+            )
+        
+        for stat_name in ['strength', 'agility', 'endurance', 'intellect']:
+            req_value = item_def.equip_requirements.get(stat_name, 0)
+            if req_value > 0 and player.get(stat_name, 0) < req_value:
+                raise HTTPException(
+                    status_code=400,
+                    detail=get_game_message('equip_stat_required', locale, stat=stat_name.capitalize(), value=req_value)
+                )
+    
     # Check if slot is valid
     valid_slots = ['head', 'torso', 'legs', 'feet', 'weapon', 'offhand', 'backpack']
     if item_def.slot not in valid_slots:
@@ -113,6 +134,10 @@ async def equip_item(
     else:
         message = get_game_message('equipped', locale, item=get_locale_string(item_def.name, locale))
     
+    # Invalidate cached derived stats (equipment changed)
+    from ..services.stats import invalidate_stats_cache
+    await invalidate_stats_cache(player_id, redis_manager)
+    
     return {
         "success": True,
         "message": message,
@@ -192,6 +217,10 @@ async def unequip_item(
         await db.drop_item(player_id, inv_item['item_id'], 1, current_user['location_id'])
         await db.remove_from_inventory(player_id, inv_item['item_id'], 1)
         
+        # Invalidate cached derived stats
+        from ..services.stats import invalidate_stats_cache
+        await invalidate_stats_cache(player_id, redis_manager)
+        
         return {
             "success": True,
             "message": get_game_message('unequip_dropped', locale, item=get_locale_string(item_def.name, locale)),
@@ -202,6 +231,10 @@ async def unequip_item(
     await db.unequip_item(player_id, unequip_req.slot)
     await db.update_inventory_item(equipped['item_id'], is_equipped=False)
     
+    # Invalidate cached derived stats
+    from ..services.stats import invalidate_stats_cache
+    await invalidate_stats_cache(player_id, redis_manager)
+    
     return {
         "success": True,
         "message": get_game_message('unequipped', locale, item=get_locale_string(item_def.name, locale)),

api/routers/game_routes.py

@@ -17,6 +17,7 @@ from .. import database as db
 from ..items import ItemsManager
 from .. import game_logic
 from ..core.websockets import manager
+from ..services.stats import STAT_CAP, invalidate_stats_cache
 
 logger = logging.getLogger(__name__)
 
@@ -457,19 +458,28 @@ async def spend_stat_point(
     if stat not in valid_stats:
         raise HTTPException(status_code=400, detail=f"Invalid stat. Must be one of: {', '.join(valid_stats)}")
     
+    # Check stat cap
+    if player[stat] >= STAT_CAP:
+        raise HTTPException(status_code=400, detail=f"{stat.capitalize()} is already at maximum ({STAT_CAP})")
+    
     # Update the stat and decrease unspent points
     update_data = {
         stat: player[stat] + 1,
         'unspent_points': player['unspent_points'] - 1
     }
     
-    # Endurance increases max HP
+    # Endurance increases max HP and max stamina
     if stat == 'endurance':
         update_data['max_hp'] = player['max_hp'] + 5
         update_data['hp'] = min(player['hp'] + 5, update_data['max_hp'])  # Also heal by 5
+        update_data['max_stamina'] = player['max_stamina'] + 2
+        update_data['stamina'] = min(player['stamina'] + 2, update_data['max_stamina'])  # Also restore by 2
     
     await db.update_character(current_user['id'], **update_data)
     
+    # Invalidate cached derived stats
+    await invalidate_stats_cache(current_user['id'], redis_manager)
+    
     return {
         "success": True,
         "message": f"Increased {stat} by 1!",
@@ -1550,4 +1560,139 @@ async def drop_item(
     return {
         "success": True,
         "message": get_game_message('dropped_item_success', locale, emoji=item_def.emoji, name=get_locale_string(item_def.name, locale), qty=quantity)
-    }
+    }
+
+
+@router.get("/api/game/character-sheet")
+async def get_character_sheet(current_user: dict = Depends(get_current_user)):
+    """Get the full character sheet with base stats, derived stats, skills, and perks."""
+    from ..services.stats import calculate_derived_stats
+    from ..services.skills import skills_manager, perks_manager, get_total_perk_points
+    
+    player = current_user
+    character_id = player['id']
+    
+    # Get derived stats
+    derived = await calculate_derived_stats(character_id, redis_manager)
+    
+    # Get available skills
+    available_skills = skills_manager.get_available_skills(player)
+    
+    # Get owned perks
+    owned_perks_rows = await db.get_character_perks(character_id)
+    owned_perk_ids = [row['perk_id'] for row in owned_perks_rows]
+    
+    # Get all perks with availability
+    all_perks = perks_manager.get_available_perks(player, owned_perk_ids)
+    
+    # Calculate perk points
+    total_perk_points = get_total_perk_points(player['level'])
+    used_perk_points = len(owned_perk_ids)
+    available_perk_points = total_perk_points - used_perk_points
+    
+    return {
+        "base_stats": {
+            "strength": player['strength'],
+            "agility": player['agility'],
+            "endurance": player['endurance'],
+            "intellect": player['intellect'],
+            "unspent_points": player['unspent_points'],
+            "stat_cap": STAT_CAP,
+        },
+        "derived_stats": derived,
+        "skills": available_skills,
+        "perks": {
+            "available_points": available_perk_points,
+            "total_points": total_perk_points,
+            "used_points": used_perk_points,
+            "all_perks": all_perks,
+        },
+        "character": {
+            "name": player['name'],
+            "level": player['level'],
+            "xp": player['xp'],
+            "hp": player['hp'],
+            "max_hp": player['max_hp'],
+            "stamina": player['stamina'],
+            "max_stamina": player['max_stamina'],
+            "avatar_data": player.get('avatar_data'),
+        }
+    }
+
+
+@router.post("/api/game/select_perk")
+async def select_perk(
+    perk_id: str,
+    current_user: dict = Depends(get_current_user)
+):
+    """Select a perk for the character."""
+    from ..services.skills import perks_manager, get_total_perk_points
+    
+    player = current_user
+    character_id = player['id']
+    
+    # Check perk exists
+    perk = perks_manager.get_perk(perk_id)
+    if not perk:
+        raise HTTPException(status_code=404, detail="Perk not found")
+    
+    # Check perk points available
+    owned_perks = await db.get_character_perks(character_id)
+    owned_perk_ids = [row['perk_id'] for row in owned_perks]
+    
+    total_points = get_total_perk_points(player['level'])
+    used_points = len(owned_perk_ids)
+    
+    if used_points >= total_points:
+        raise HTTPException(status_code=400, detail="No perk points available")
+    
+    # Check if already owned
+    if perk_id in owned_perk_ids:
+        raise HTTPException(status_code=400, detail="Perk already selected")
+    
+    # Check requirements
+    if not perks_manager.check_requirements(perk, player):
+        raise HTTPException(status_code=400, detail="Requirements not met for this perk")
+    
+    # Add perk
+    success = await db.add_character_perk(character_id, perk_id)
+    if not success:
+        raise HTTPException(status_code=400, detail="Failed to select perk")
+    
+    # Invalidate stats cache (perks affect derived stats)
+    await invalidate_stats_cache(character_id, redis_manager)
+    
+    return {
+        "success": True,
+        "message": f"Perk '{perk_id}' selected!",
+        "perk": {
+            "id": perk.id,
+            "name": perk.name,
+            "description": perk.description,
+            "icon": perk.icon,
+        }
+    }
+
+
+@router.get("/api/game/available-skills")
+async def get_available_skills(current_user: dict = Depends(get_current_user)):
+    """Get available skills for the combat UI abilities dropdown."""
+    from ..services.skills import skills_manager
+    from .. import database as db
+    
+    player = current_user
+    all_skills = skills_manager.get_available_skills(player)
+    
+    # Check cooldowns
+    effects = await db.get_player_effects(player['id'])
+    cooldowns = {eff['source']: eff['ticks_remaining'] for eff in effects if eff.get('effect_type') == 'cooldown'}
+    
+    # Only return unlocked skills for the combat dropdown
+    unlocked = []
+    for s in all_skills:
+        if s['unlocked']:
+            cd_source = f"cd:{s['id']}"
+            s['current_cooldown'] = cooldowns.get(cd_source, 0)
+            unlocked.append(s)
+            
+    return {"skills": unlocked}

api/routers/loot.py

@@ -195,9 +195,13 @@ async def loot_corpse(
     # Parse corpse ID
     corpse_type, corpse_db_id = req.corpse_id.split('_', 1)
     corpse_db_id = int(corpse_db_id)
-    
     player = current_user  # current_user is already the character dict
     
+    # Get player derived stats for loot quality
+    from ..services.stats import calculate_derived_stats
+    stats = await calculate_derived_stats(player['id'], redis_manager)
+    loot_quality = stats.get('loot_quality', 1.0)
+    
     # Get player's current capacity
     inventory = await db.get_inventory(player['id'])
     current_weight, max_weight, current_volume, max_volume = await calculate_player_capacity(inventory, ITEMS_MANAGER)
@@ -246,7 +250,6 @@ async def loot_corpse(
                 success, error_msg, tools_consumed = await consume_tool_durability(player['id'], tool_req, inventory)
                 if not success:
                     raise HTTPException(status_code=400, detail=error_msg)
-            
             # Determine quantity
             quantity = random.randint(loot_item['quantity_min'], loot_item['quantity_max'])
             
@@ -254,6 +257,13 @@ async def loot_corpse(
                 # Check if item fits in inventory
                 item_def = ITEMS_MANAGER.get_item(loot_item['item_id'])
                 if item_def:
+                    # Apply loot quality bonus for resources and consumables
+                    if getattr(item_def, 'category', item_def.type) in ['resource', 'consumable'] and loot_quality > 1.0:
+                        # e.g., loot_quality 1.15 = 15% chance for +1 extra
+                        bonus_chance = loot_quality - 1.0
+                        if random.random() < bonus_chance:
+                            quantity += 1
+                            
                     item_weight = item_def.weight * quantity
                     item_volume = item_def.volume * quantity
                     
@@ -305,11 +315,16 @@ async def loot_corpse(
                 if can_loot:
                     # Can loot this item
                     quantity = random.randint(loot_item['quantity_min'], loot_item['quantity_max'])
-                    
                     if quantity > 0:
                         # Check if item fits in inventory
                         item_def = ITEMS_MANAGER.get_item(loot_item['item_id'])
                         if item_def:
+                            # Apply loot quality bonus for resources and consumables
+                            if getattr(item_def, 'category', item_def.type) in ['resource', 'consumable'] and loot_quality > 1.0:
+                                bonus_chance = loot_quality - 1.0
+                                if random.random() < bonus_chance:
+                                    quantity += 1
+                                    
                             item_weight = item_def.weight * quantity
                             item_volume = item_def.volume * quantity
                             

api/services/helpers.py

@@ -72,6 +72,8 @@ GAME_MESSAGES = {
     'unequipped': {'en': "Unequipped {item}", 'es': "Desequipado {item}"},
     'unequip_dropped': {'en': "Unequipped {item} (dropped to ground - inventory full)", 'es': "Desequipado {item} (tirado al suelo - inventario lleno)"},
     'repaired_success': {'en': "Repaired {item}! Restored {amount} durability.", 'es': "¡Reparado {item}! Restaurados {amount} puntos de durabilidad."},
+    'equip_level_required': {'en': "Requires level {level} to equip", 'es': "Requiere nivel {level} para equipar"},
+    'equip_stat_required': {'en': "Requires {stat} {value} to equip", 'es': "Requiere {stat} {value} para equipar"},
 
     # Characters/Auth
     'character_created': {'en': "Character created successfully", 'es': "Personaje creado con éxito"},