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+# Colosseum - Unity Game Project
+
+## Project Overview
+
+Multiplayer arena game built with **Unity 6000.3.10f1** and **Unity Netcode for GameObjects**.
+
+- **Language**: C# 9.0
+- **Target Framework**: .NET Standard 2.1
+- **Root Namespace**: `Colosseum`
+- **Assembly Definition**: `Colosseum.Game` (Assets/Scripts/Colosseum.Game.asmdef)
+
+## Game Design Documentation
+
+Design docs are maintained in Obsidian Vault: `C:\Users\dal4s\OneDrive\문서\Obsidian Vault\Colosseum`
+
+### Game Concept
+- **Genre**: Online multiplayer co-op action RPG (3rd person)
+- **Theme**: Gladiator survival boss raid in Colosseum
+- **Roles**: Multi-role system - players can hybridize (e.g., Tank 0.5 + DPS 0.5) instead of fixed Tank/DPS/Healer
+
+### Stats System
+
+| Stat | Abbr | Description | Derived Formula |
+|------|------|-------------|-----------------|
+| Strength | STR | Weapon damage | Physical Damage = STR × 2 |
+| Dexterity | DEX | Ranged aim/damage, melee speed | Ranged Damage = DEX × 2 |
+| Intelligence | INT | Magic damage | Magic Damage = INT × 2 |
+| Vitality | VIT | Max health | Max HP = VIT × 10 |
+| Wisdom | WIS | Healing power | Heal Power = WIS × 1.5 |
+| Spirit | SPI | Max mana | Max MP = SPI × 5 |
+
+### Damage Calculation
+
+```
+Final Damage = baseDamage + (statDamage × statScaling)
+```
+
+| DamageType | Base Stat | Description |
+|------------|-----------|-------------|
+| Physical | STR | Melee weapon damage |
+| Magical | INT | Spell damage |
+| Ranged | DEX | Bow/ranged damage |
+| True | None | Fixed damage, no stat scaling |
+
+### Stat Modifier System
+
+Modifiers are applied in order:
+1. **Flat**: Add fixed value
+2. **PercentAdd**: Sum percentages, then multiply
+3. **PercentMult**: Multiply individually
+
+```
+Final = (Base + FlatSum) × (1 + PercentAddSum) × PercentMult1 × PercentMult2...
+```
+
+### Skill System
+- **Active Skills**: 6 slots (L-click, R-click, 1, 2, 3, 4)
+- **Passive Skills**: Tree-based progression from center
+- **Effects**: Triggered via animation events (`OnEffect(index)`)
+- **Animation**: Start clip + optional end clip
+
+## Build/Run Commands
+
+This is a Unity project. Use Unity Editor for building and testing.
+
+```bash
+# Open in Unity Editor (requires Unity Hub)
+# Build via: File > Build Settings > Build
+
+# Run tests in Unity Editor
+# Window > General > Test Runner > EditMode / PlayMode
+```
+
+### Build from Command Line (Windows)
+
+```bash
+# Build Windows standalone (adjust paths as needed)
+"C:\Program Files\Unity\Hub\Editor\6000.3.10f1\Editor\Unity.exe" -batchmode -projectPath . -buildWindows64Player ./Builds/Windows/Colosseum.exe -quit
+```
+
+## Project Structure
+
+```
+Assets/
+  Scripts/
+    Abnormalities/    # Buff/debuff system
+    Editor/           # Unity editor extensions
+    Network/          # Network management
+    Player/           # Player controllers
+    Skills/           # Skill system
+      Effects/        # Skill effects (damage, heal, etc.)
+    Stats/            # Character statistics
+    UI/               # User interface
+```
+
+## Code Style Guidelines
+
+### Namespaces
+
+Follow `Colosseum.{Subnamespace}` pattern:
+
+```csharp
+namespace Colosseum.Player { }
+namespace Colosseum.Skills { }
+namespace Colosseum.Skills.Effects { }
+namespace Colosseum.Stats { }
+namespace Colosseum.Network { }
+namespace Colosseum.Abnormalities { }
+```
+
+### Using Statements Order
+
+Organize imports in this order, separated by blank lines:
+
+1. System namespaces
+2. UnityEngine namespaces
+3. Unity.Netcode / Unity packages
+4. Colosseum namespaces
+
+```csharp
+using System;
+using System.Collections.Generic;
+
+using UnityEngine;
+
+using Unity.Netcode;
+
+using Colosseum.Stats;
+using Colosseum.Player;
+```
+
+### Naming Conventions
+
+| Element | Convention | Example |
+|---------|------------|---------|
+| Classes | PascalCase | `PlayerNetworkController` |
+| Interfaces | IPascalCase | `IDamageable` |
+| Methods | PascalCase | `TakeDamageRpc()` |
+| Public Properties | PascalCase | `MaxHealth`, `IsStunned` |
+| Private Fields | camelCase | `currentHealth`, `characterStats` |
+| Constants | PascalCase or SCREAMING_SNAKE | `SKILL_STATE_NAME`, `MaxValue` |
+| Enum values | PascalCase | `DamageType.Physical` |
+
+### Serialization & Inspector
+
+Use `[SerializeField]` with `[Header]` and `[Tooltip]` for organization:
+
+```csharp
+[Header("References")]
+[Tooltip("CharacterStats component (auto-searched if null)")]
+[SerializeField] private CharacterStats characterStats;
+
+[Header("Settings")]
+[Min(0f)] [SerializeField] private float baseDamage = 10f;
+[SerializeField] private DamageType damageType = DamageType.Physical;
+```
+
+### Documentation
+
+Use XML documentation comments in **Korean**:
+
+```csharp
+/// <summary>
+/// 플레이어 네트워크 상태 관리 (HP, MP 등)
+/// </summary>
+public class PlayerNetworkController : NetworkBehaviour
+{
+    /// <summary>
+    /// 대미지 적용 (서버에서만 실행)
+    /// </summary>
+    [Rpc(SendTo.Server)]
+    public void TakeDamageRpc(float damage)
+    {
+        // ...
+    }
+}
+```
+
+### Network Code Patterns
+
+Use Unity Netcode patterns:
+
+```csharp
+// Network variables for synchronized state
+private NetworkVariable<float> currentHealth = new NetworkVariable<float>(100f);
+
+// Server RPCs for client-to-server calls
+[Rpc(SendTo.Server)]
+public void TakeDamageRpc(float damage)
+{
+    currentHealth.Value = Mathf.Max(0f, currentHealth.Value - damage);
+}
+
+// Check authority before modifying
+if (IsServer)
+{
+    currentHealth.Value = MaxHealth;
+}
+```
+
+### Expression Body Members
+
+Use for simple properties and methods:
+
+```csharp
+public float MaxHealth => vitality.FinalValue * 10f;
+public bool IsStunned => stunCount > 0;
+public bool CanAct => !IsStunned;
+```
+
+### Switch Expressions
+
+Prefer switch expressions for concise mapping:
+
+```csharp
+public CharacterStat GetStat(StatType statType)
+{
+    return statType switch
+    {
+        StatType.Strength => strength,
+        StatType.Dexterity => dexterity,
+        StatType.Intelligence => intelligence,
+        _ => null,
+    };
+}
+```
+
+### ScriptableObjects for Data
+
+Use ScriptableObject for configuration data:
+
+```csharp
+[CreateAssetMenu(fileName = "NewSkill", menuName = "Colosseum/Skill")]
+public class SkillData : ScriptableObject
+{
+    [SerializeField] private string skillName;
+    [SerializeField] private List<SkillEffect> effects;
+    
+    public string SkillName => skillName;
+    public IReadOnlyList<SkillEffect> Effects => effects;
+}
+```
+
+### Error Handling
+
+- Use `Debug.LogWarning()` for recoverable issues
+- Use `Debug.LogError()` for critical failures
+- Null-check parameters in public methods
+
+```csharp
+public void ApplyAbnormality(AbnormalityData data, GameObject source)
+{
+    if (data == null)
+    {
+        Debug.LogWarning("[Abnormality] ApplyAbnormality called with null data");
+        return;
+    }
+    // ...
+}
+```
+
+### Events
+
+Use C# events with `Action<T>` or custom delegates:
+
+```csharp
+public event Action<ActiveAbnormality> OnAbnormalityAdded;
+public event Action<ActiveAbnormality> OnAbnormalityRemoved;
+public event Action OnAbnormalitiesChanged;
+
+// Invoke with null-conditional
+OnAbnormalityAdded?.Invoke(newAbnormality);
+```
+
+## Key Dependencies
+
+| Package | Purpose |
+|---------|---------|
+| Unity.Netcode.Runtime | Multiplayer networking |
+| Unity.InputSystem | New input system |
+| Unity.TextMeshPro | Text rendering |
+| Unity.Networking.Transport | Low-level networking |
+
+## Common Patterns
+
+### MonoBehaviour Components
+
+```csharp
+public class ExampleComponent : MonoBehaviour
+{
+    [Header("References")]
+    [SerializeField] private Animator animator;
+    
+    public Animator Animator => animator;
+    
+    private void Awake()
+    {
+        if (animator == null)
+            animator = GetComponentInChildren<Animator>();
+    }
+}
+```
+
+### NetworkBehaviour Components
+
+```csharp
+public class NetworkedComponent : NetworkBehaviour
+{
+    private NetworkVariable<int> value = new NetworkVariable<int>();
+    
+    public override void OnNetworkSpawn()
+    {
+        // Initialize networked state
+    }
+    
+    public override void OnNetworkDespawn()
+    {
+        // Cleanup
+    }
+}
+```
+
+## Notes
+
+- All code comments and documentation should be in Korean
+- Use `[Min()]` attribute for numeric minimums in Inspector
+- Use `[TextArea]` for multi-line string fields
+- Private fields should use `camelCase` (no `m_` or `_` prefix)
+- Prefer `IReadOnlyList<T>` for exposing collections