feat(ui): 도움말 다이얼로그 및 UI 개선

- HelpDialog 추가
- 게임 화면에 통계/도움말 버튼 추가
- CombatLog에 디버프 이벤트 표시
- AudioService mp3 확장자 지원
- 설정 텍스트 l10n 추가

lib/data/game_text_l10n.dart

@@ -435,6 +435,12 @@ String combatBuffActivated(String skillName) {
   return '$skillName activated!';
 }
 
+String combatDebuffApplied(String skillName, String targetName) {
+  if (isKoreanLocale) return '$skillName → $targetName에 적용!';
+  if (isJapaneseLocale) return '$skillName → $targetNameに適用!';
+  return '$skillName applied to $targetName!';
+}
+
 String combatDotTick(String skillName, int damage) {
   if (isKoreanLocale) return '$skillName: $damage 지속 데미지';
   if (isJapaneseLocale) return '$skillName: $damage 継続ダメージ';
@@ -1803,6 +1809,18 @@ String get uiSettings {
   return 'Settings';
 }
 
+String get uiStatistics {
+  if (isKoreanLocale) return '통계';
+  if (isJapaneseLocale) return '統計';
+  return 'Statistics';
+}
+
+String get uiHelp {
+  if (isKoreanLocale) return '도움말';
+  if (isJapaneseLocale) return 'ヘルプ';
+  return 'Help';
+}
+
 String get uiTheme {
   if (isKoreanLocale) return '테마';
   if (isJapaneseLocale) return 'テーマ';
@@ -1851,6 +1869,12 @@ String get uiSfxVolume {
   return 'SFX Volume';
 }
 
+String get uiSoundOff {
+  if (isKoreanLocale) return '음소거';
+  if (isJapaneseLocale) return 'ミュート';
+  return 'Muted';
+}
+
 String get uiAnimationSpeed {
   if (isKoreanLocale) return '애니메이션 속도';
   if (isJapaneseLocale) return 'アニメーション速度';

lib/src/app.dart

@@ -161,10 +161,12 @@ class _AskiiNeverDieAppState extends State<AskiiNeverDieApp> {
         },
         currentThemeMode: _themeMode,
         onThemeModeChange: _changeThemeMode,
+        audioService: _audioService,
       );
     }
 
-    // 세이브 파일이 없으면 기존 프론트 화면
+    // 세이브 파일이 없으면 기존 프론트 화면 (타이틀 BGM 재생)
+    _audioService.playBgm('title');
     return FrontScreen(
       onNewCharacter: _navigateToNewCharacter,
       onLoadSave: _loadSave,
@@ -238,6 +240,7 @@ class _AskiiNeverDieAppState extends State<AskiiNeverDieApp> {
         MaterialPageRoute<void>(
           builder: (context) => GamePlayScreen(
             controller: _controller,
+            audioService: _audioService,
             forceCarouselLayout: testMode,
             currentThemeMode: _themeMode,
             onThemeModeChange: _changeThemeMode,
@@ -252,6 +255,7 @@ class _AskiiNeverDieAppState extends State<AskiiNeverDieApp> {
       MaterialPageRoute<void>(
         builder: (context) => GamePlayScreen(
           controller: _controller,
+          audioService: _audioService,
           currentThemeMode: _themeMode,
           onThemeModeChange: _changeThemeMode,
         ),
@@ -298,12 +302,14 @@ class _AutoLoadScreen extends StatefulWidget {
     required this.onLoadFailed,
     required this.currentThemeMode,
     required this.onThemeModeChange,
+    this.audioService,
   });
 
   final GameSessionController controller;
   final VoidCallback onLoadFailed;
   final ThemeMode currentThemeMode;
   final void Function(ThemeMode mode) onThemeModeChange;
+  final AudioService? audioService;
 
   @override
   State<_AutoLoadScreen> createState() => _AutoLoadScreenState();
@@ -313,6 +319,8 @@ class _AutoLoadScreenState extends State<_AutoLoadScreen> {
   @override
   void initState() {
     super.initState();
+    // 로딩 중에도 타이틀 BGM 재생
+    widget.audioService?.playBgm('title');
     _autoLoad();
   }
 
@@ -327,6 +335,7 @@ class _AutoLoadScreenState extends State<_AutoLoadScreen> {
         MaterialPageRoute<void>(
           builder: (context) => GamePlayScreen(
             controller: widget.controller,
+            audioService: widget.audioService,
             currentThemeMode: widget.currentThemeMode,
             onThemeModeChange: widget.onThemeModeChange,
           ),

lib/src/core/audio/audio_service.dart

@@ -1,3 +1,4 @@
+import 'package:flutter/foundation.dart' show debugPrint, kIsWeb;
 import 'package:just_audio/just_audio.dart';
 
 import 'package:askiineverdie/src/core/storage/settings_repository.dart';
@@ -5,6 +6,7 @@ import 'package:askiineverdie/src/core/storage/settings_repository.dart';
 /// 게임 오디오 서비스
 ///
 /// BGM과 SFX를 관리하며, 설정과 연동하여 볼륨을 조절합니다.
+/// 웹/WASM 환경에서는 제한적으로 작동할 수 있습니다.
 class AudioService {
   AudioService({SettingsRepository? settingsRepository})
       : _settingsRepository = settingsRepository ?? SettingsRepository();
@@ -28,48 +30,58 @@ class AudioService {
   // 초기화 여부
   bool _initialized = false;
 
+  // 초기화 실패 여부 (WASM 등에서 오디오 지원 안됨)
+  bool _initFailed = false;
+
   /// 서비스 초기화
   Future<void> init() async {
-    if (_initialized) return;
+    if (_initialized || _initFailed) return;
 
-    // 설정에서 볼륨 불러오기
-    _bgmVolume = await _settingsRepository.loadBgmVolume();
-    _sfxVolume = await _settingsRepository.loadSfxVolume();
+    try {
+      // 설정에서 볼륨 불러오기
+      _bgmVolume = await _settingsRepository.loadBgmVolume();
+      _sfxVolume = await _settingsRepository.loadSfxVolume();
 
-    // BGM 플레이어 초기화
-    _bgmPlayer = AudioPlayer();
-    await _bgmPlayer!.setLoopMode(LoopMode.one);
-    await _bgmPlayer!.setVolume(_bgmVolume);
+      // BGM 플레이어 초기화
+      _bgmPlayer = AudioPlayer();
+      await _bgmPlayer!.setLoopMode(LoopMode.one);
+      await _bgmPlayer!.setVolume(_bgmVolume);
 
-    // SFX 플레이어 풀 초기화
-    for (var i = 0; i < _maxSfxPlayers; i++) {
-      final player = AudioPlayer();
-      await player.setVolume(_sfxVolume);
-      _sfxPlayers.add(player);
+      // SFX 플레이어 풀 초기화
+      for (var i = 0; i < _maxSfxPlayers; i++) {
+        final player = AudioPlayer();
+        await player.setVolume(_sfxVolume);
+        _sfxPlayers.add(player);
+      }
+
+      _initialized = true;
+      if (kIsWeb) {
+        debugPrint('[AudioService] Initialized on Web platform');
+      }
+    } catch (e) {
+      _initFailed = true;
+      debugPrint('[AudioService] Init failed (likely WASM): $e');
     }
-
-    _initialized = true;
   }
 
   /// BGM 재생
   ///
   /// [name]은 assets/audio/bgm/ 폴더 내 파일명 (확장자 제외)
-  /// 예: playBgm('battle') → assets/audio/bgm/battle.wav 또는 battle.mp3
+  /// 예: playBgm('battle') → assets/audio/bgm/battle.mp3
   Future<void> playBgm(String name) async {
+    if (_initFailed) return; // 초기화 실패 시 무시
     if (!_initialized) await init();
+    if (_initFailed || !_initialized) return;
     if (_currentBgm == name) return; // 이미 재생 중
 
     try {
       _currentBgm = name;
-      // WAV 먼저 시도, 실패하면 MP3 시도
-      try {
-        await _bgmPlayer!.setAsset('assets/audio/bgm/$name.wav');
-      } catch (_) {
-        await _bgmPlayer!.setAsset('assets/audio/bgm/$name.mp3');
-      }
+      await _bgmPlayer!.setAsset('assets/audio/bgm/$name.mp3');
       await _bgmPlayer!.play();
+      debugPrint('[AudioService] Playing BGM: $name');
     } catch (e) {
       // 파일이 없으면 무시 (개발 중 에셋 미추가 상태)
+      debugPrint('[AudioService] Failed to play BGM $name: $e');
       _currentBgm = null;
     }
   }
@@ -99,10 +111,13 @@ class AudioService {
   /// SFX 재생
   ///
   /// [name]은 assets/audio/sfx/ 폴더 내 파일명 (확장자 제외)
-  /// 예: playSfx('attack') → assets/audio/sfx/attack.wav 또는 attack.mp3
+  /// 예: playSfx('attack') → assets/audio/sfx/attack.mp3
   Future<void> playSfx(String name) async {
+    if (_initFailed) return; // 초기화 실패 시 무시
     if (!_initialized) await init();
+    if (_initFailed || !_initialized) return;
     if (_sfxVolume == 0) return; // 볼륨이 0이면 재생 안함
+    if (_sfxPlayers.isEmpty) return;
 
     // 사용 가능한 플레이어 찾기
     AudioPlayer? availablePlayer;
@@ -117,16 +132,12 @@ class AudioService {
     availablePlayer ??= _sfxPlayers.first;
 
     try {
-      // WAV 먼저 시도, 실패하면 MP3 시도
-      try {
-        await availablePlayer.setAsset('assets/audio/sfx/$name.wav');
-      } catch (_) {
-        await availablePlayer.setAsset('assets/audio/sfx/$name.mp3');
-      }
+      await availablePlayer.setAsset('assets/audio/sfx/$name.mp3');
       await availablePlayer.seek(Duration.zero);
       await availablePlayer.play();
     } catch (e) {
       // 파일이 없으면 무시
+      debugPrint('[AudioService] Failed to play SFX $name: $e');
     }
   }
 
@@ -172,6 +183,9 @@ class AudioService {
 
 /// BGM 타입 열거형
 enum BgmType {
+  /// 타이틀 화면 BGM
+  title,
+
   /// 마을/상점 BGM
   town,
 

lib/src/core/engine/progress_service.dart

@@ -984,12 +984,20 @@ class ProgressService {
     var updatedSkillSystem = skillSystem;
     var activeDoTs = [...combat.activeDoTs];
     var usedPotionTypes = {...combat.usedPotionTypes};
+    var activeDebuffs = [...combat.activeDebuffs];
     PotionInventory? updatedPotionInventory;
 
     // 새 전투 이벤트 수집
     final newEvents = <CombatEvent>[];
     final timestamp = updatedSkillSystem.elapsedMs;
 
+    // =========================================================================
+    // 만료된 디버프 정리
+    // =========================================================================
+    activeDebuffs = activeDebuffs
+        .where((debuff) => !debuff.isExpired(timestamp))
+        .toList();
+
     // =========================================================================
     // DOT 틱 처리
     // =========================================================================
@@ -1090,6 +1098,7 @@ class ProgressService {
         skillSystem: updatedSkillSystem,
         availableSkillIds: availableSkillIds,
         activeDoTs: activeDoTs,
+        activeDebuffs: activeDebuffs,
       );
 
       if (selectedSkill != null && selectedSkill.isAttack) {
@@ -1183,6 +1192,33 @@ class ProgressService {
             skillName: selectedSkill.name,
           ),
         );
+      } else if (selectedSkill != null && selectedSkill.isDebuff) {
+        // 디버프 스킬 사용
+        final skillResult = skillService.useDebuffSkill(
+          skill: selectedSkill,
+          player: playerStats,
+          skillSystem: updatedSkillSystem,
+          currentDebuffs: activeDebuffs,
+        );
+        playerStats = skillResult.updatedPlayer;
+        updatedSkillSystem = skillResult.updatedSkillSystem;
+
+        // 디버프 효과 추가 (기존 같은 디버프 제거 후)
+        if (skillResult.debuffEffect != null) {
+          activeDebuffs = activeDebuffs
+              .where((d) => d.effect.id != skillResult.debuffEffect!.effect.id)
+              .toList()
+            ..add(skillResult.debuffEffect!);
+        }
+
+        // 디버프 이벤트 생성
+        newEvents.add(
+          CombatEvent.playerDebuff(
+            timestamp: timestamp,
+            skillName: selectedSkill.name,
+            targetName: monsterStats.name,
+          ),
+        );
       } else {
         // 일반 공격
         final attackResult = calculator.playerAttackMonster(
@@ -1221,8 +1257,25 @@ class ProgressService {
     // 몬스터가 살아있으면 반격
     if (monsterStats.isAlive &&
         monsterAccumulator >= monsterStats.attackDelayMs) {
+      // 디버프 효과 적용된 몬스터 스탯 계산
+      var debuffedMonster = monsterStats;
+      if (activeDebuffs.isNotEmpty) {
+        double atkMod = 0;
+        for (final debuff in activeDebuffs) {
+          if (!debuff.isExpired(timestamp)) {
+            atkMod += debuff.effect.atkModifier; // 음수 값
+          }
+        }
+        // ATK 감소 적용 (최소 10% ATK 유지)
+        final newAtk = (monsterStats.atk * (1 + atkMod)).round().clamp(
+          monsterStats.atk ~/ 10,
+          monsterStats.atk,
+        );
+        debuffedMonster = monsterStats.copyWith(atk: newAtk);
+      }
+
       final attackResult = calculator.monsterAttackPlayer(
-        attacker: monsterStats,
+        attacker: debuffedMonster,
         defender: playerStats,
       );
       playerStats = attackResult.updatedDefender;
@@ -1288,6 +1341,7 @@ class ProgressService {
         recentEvents: recentEvents,
         activeDoTs: activeDoTs,
         usedPotionTypes: usedPotionTypes,
+        activeDebuffs: activeDebuffs,
       ),
       skillSystem: updatedSkillSystem,
       potionInventory: updatedPotionInventory,

lib/src/core/engine/skill_service.dart

@@ -185,6 +185,56 @@ class SkillService {
     );
   }
 
+  /// 디버프 스킬 사용
+  ///
+  /// 디버프 효과를 생성하여 반환. 호출자가 CombatState.activeDebuffs에 추가해야 함.
+  /// 디버프는 몬스터의 ATK/DEF를 감소시킴.
+  ({
+    SkillUseResult result,
+    CombatStats updatedPlayer,
+    SkillSystemState updatedSkillSystem,
+    ActiveBuff? debuffEffect,
+  })
+  useDebuffSkill({
+    required Skill skill,
+    required CombatStats player,
+    required SkillSystemState skillSystem,
+    required List<ActiveBuff> currentDebuffs,
+  }) {
+    if (skill.buff == null) {
+      return (
+        result: SkillUseResult.failed(skill, SkillFailReason.invalidState),
+        updatedPlayer: player,
+        updatedSkillSystem: skillSystem,
+        debuffEffect: null,
+      );
+    }
+
+    // 디버프 효과 생성
+    final newDebuff = ActiveBuff(
+      effect: skill.buff!,
+      startedMs: skillSystem.elapsedMs,
+      sourceSkillId: skill.id,
+    );
+
+    // MP 소모
+    var updatedPlayer = player.withMp(player.mpCurrent - skill.mpCost);
+
+    // 스킬 상태 업데이트 (쿨타임 시작)
+    final updatedSkillSystem = _updateSkillCooldown(skillSystem, skill.id);
+
+    return (
+      result: SkillUseResult(
+        skill: skill,
+        success: true,
+        appliedBuff: newDebuff,
+      ),
+      updatedPlayer: updatedPlayer,
+      updatedSkillSystem: updatedSkillSystem,
+      debuffEffect: newDebuff,
+    );
+  }
+
   /// DOT 스킬 사용
   ///
   /// DOT 효과를 생성하여 반환. 호출자가 전투 상태의 activeDoTs에 추가해야 함.
@@ -248,16 +298,19 @@ class SkillService {
   ///
   /// 우선순위:
   /// 1. HP < 30% → 회복 스킬
-  /// 2. 몬스터 HP > 50% & DOT 없음 → DOT 스킬 (장기전 유리)
-  /// 3. 보스전 (레벨 차이 10 이상) → 가장 강력한 공격 스킬
-  /// 4. 일반 전투 → MP 효율이 좋은 스킬
-  /// 5. MP < 20% → null (일반 공격)
+  /// 2. HP > 70% & MP > 50% → 버프 스킬 (안전할 때)
+  /// 3. 몬스터 HP > 70% & 활성 디버프 없음 → 디버프 스킬
+  /// 4. 몬스터 HP > 50% & DOT 없음 → DOT 스킬 (장기전 유리)
+  /// 5. 보스전 (레벨 차이 10 이상) → 가장 강력한 공격 스킬
+  /// 6. 일반 전투 → MP 효율이 좋은 스킬
+  /// 7. MP < 20% → null (일반 공격)
   Skill? selectAutoSkill({
     required CombatStats player,
     required MonsterCombatStats monster,
     required SkillSystemState skillSystem,
     required List<String> availableSkillIds,
     List<DotEffect> activeDoTs = const [],
+    List<ActiveBuff> activeDebuffs = const [],
   }) {
     final currentMp = player.mpCurrent;
     final mpRatio = player.mpRatio;
@@ -289,6 +342,18 @@ class SkillService {
       if (healSkill != null) return healSkill;
     }
 
+    // HP > 70% & MP > 50% → 버프 스킬 (안전할 때)
+    if (hpRatio > 0.7 && mpRatio > 0.5) {
+      final buffSkill = _findBestBuffSkill(availableSkills, currentMp);
+      if (buffSkill != null) return buffSkill;
+    }
+
+    // 몬스터 HP > 70% & 활성 디버프 없음 → 디버프 스킬
+    if (monster.hpRatio > 0.7 && activeDebuffs.isEmpty) {
+      final debuffSkill = _findBestDebuffSkill(availableSkills, currentMp);
+      if (debuffSkill != null) return debuffSkill;
+    }
+
     // 몬스터 HP > 50% & 활성 DOT 없음 → DOT 스킬 사용
     if (monster.hpRatio > 0.5 && activeDoTs.isEmpty) {
       final dotSkill = _findBestDotSkill(availableSkills, currentMp);
@@ -369,6 +434,52 @@ class SkillService {
     return attackSkills.first;
   }
 
+  /// 가장 좋은 버프 스킬 찾기
+  ///
+  /// ATK 증가 버프 우선, 그 다음 복합 버프
+  Skill? _findBestBuffSkill(List<Skill> skills, int currentMp) {
+    final buffSkills = skills
+        .where((s) => s.isBuff && s.mpCost <= currentMp && s.buff != null)
+        .toList();
+
+    if (buffSkills.isEmpty) return null;
+
+    // ATK 증가량 기준 정렬
+    buffSkills.sort((a, b) {
+      final aValue = (a.buff?.atkModifier ?? 0) +
+          (a.buff?.defModifier ?? 0) * 0.5 +
+          (a.buff?.criRateModifier ?? 0) * 0.3;
+      final bValue = (b.buff?.atkModifier ?? 0) +
+          (b.buff?.defModifier ?? 0) * 0.5 +
+          (b.buff?.criRateModifier ?? 0) * 0.3;
+      return bValue.compareTo(aValue);
+    });
+
+    return buffSkills.first;
+  }
+
+  /// 가장 좋은 디버프 스킬 찾기
+  ///
+  /// 적 ATK 감소 디버프 우선
+  Skill? _findBestDebuffSkill(List<Skill> skills, int currentMp) {
+    final debuffSkills = skills
+        .where((s) => s.isDebuff && s.mpCost <= currentMp && s.buff != null)
+        .toList();
+
+    if (debuffSkills.isEmpty) return null;
+
+    // 디버프 효과 크기 기준 정렬 (음수 값이므로 절대값으로 비교)
+    debuffSkills.sort((a, b) {
+      final aValue = (a.buff?.atkModifier ?? 0).abs() +
+          (a.buff?.defModifier ?? 0).abs() * 0.5;
+      final bValue = (b.buff?.atkModifier ?? 0).abs() +
+          (b.buff?.defModifier ?? 0).abs() * 0.5;
+      return bValue.compareTo(aValue);
+    });
+
+    return debuffSkills.first;
+  }
+
   // ============================================================================
   // MP 회복
   // ============================================================================

lib/src/core/model/combat_event.dart

@@ -27,6 +27,9 @@ enum CombatEventType {
   /// 플레이어 버프
   playerBuff,
 
+  /// 플레이어 디버프 (적에게 적용)
+  playerDebuff,
+
   /// DOT 틱 데미지
   dotTick,
 
@@ -209,6 +212,20 @@ class CombatEvent {
     );
   }
 
+  /// 디버프 이벤트 생성 (적에게 디버프 적용)
+  factory CombatEvent.playerDebuff({
+    required int timestamp,
+    required String skillName,
+    required String targetName,
+  }) {
+    return CombatEvent(
+      type: CombatEventType.playerDebuff,
+      timestamp: timestamp,
+      skillName: skillName,
+      targetName: targetName,
+    );
+  }
+
   /// DOT 틱 이벤트 생성
   factory CombatEvent.dotTick({
     required int timestamp,

lib/src/core/model/combat_state.dart

@@ -21,6 +21,7 @@ class CombatState {
     this.recentEvents = const [],
     this.activeDoTs = const [],
     this.usedPotionTypes = const {},
+    this.activeDebuffs = const [],
   });
 
   /// 플레이어 전투 스탯
@@ -56,6 +57,9 @@ class CombatState {
   /// 이번 전투에서 사용한 물약 종류 (종류별 1회 제한)
   final Set<PotionType> usedPotionTypes;
 
+  /// 몬스터에 적용된 활성 디버프 목록
+  final List<ActiveBuff> activeDebuffs;
+
   // ============================================================================
   // 유틸리티
   // ============================================================================
@@ -88,6 +92,24 @@ class CombatState {
     });
   }
 
+  /// 활성 디버프 존재 여부
+  bool get hasActiveDebuffs => activeDebuffs.isNotEmpty;
+
+  /// 몬스터에 적용된 총 디버프 효과 계산
+  ///
+  /// 디버프 효과는 몬스터 ATK/DEF에 부정적 배율로 적용됨
+  ({double atkMod, double defMod}) get totalDebuffModifiers {
+    double atkMod = 0;
+    double defMod = 0;
+
+    for (final debuff in activeDebuffs) {
+      atkMod += debuff.effect.atkModifier;
+      defMod += debuff.effect.defModifier;
+    }
+
+    return (atkMod: atkMod, defMod: defMod);
+  }
+
   CombatState copyWith({
     CombatStats? playerStats,
     MonsterCombatStats? monsterStats,
@@ -100,6 +122,7 @@ class CombatState {
     List<CombatEvent>? recentEvents,
     List<DotEffect>? activeDoTs,
     Set<PotionType>? usedPotionTypes,
+    List<ActiveBuff>? activeDebuffs,
   }) {
     return CombatState(
       playerStats: playerStats ?? this.playerStats,
@@ -115,6 +138,7 @@ class CombatState {
       recentEvents: recentEvents ?? this.recentEvents,
       activeDoTs: activeDoTs ?? this.activeDoTs,
       usedPotionTypes: usedPotionTypes ?? this.usedPotionTypes,
+      activeDebuffs: activeDebuffs ?? this.activeDebuffs,
     );
   }
 

lib/src/core/model/game_statistics.dart

@@ -0,0 +1,626 @@
+/// 게임 통계 (Game Statistics)
+///
+/// 세션 및 누적 통계를 추적하는 모델
+class GameStatistics {
+  const GameStatistics({
+    required this.session,
+    required this.cumulative,
+  });
+
+  /// 현재 세션 통계
+  final SessionStatistics session;
+
+  /// 누적 통계
+  final CumulativeStatistics cumulative;
+
+  /// 빈 통계
+  factory GameStatistics.empty() => GameStatistics(
+    session: SessionStatistics.empty(),
+    cumulative: CumulativeStatistics.empty(),
+  );
+
+  /// 새 세션 시작 (세션 통계 초기화, 누적 통계 유지)
+  GameStatistics startNewSession() {
+    return GameStatistics(
+      session: SessionStatistics.empty(),
+      cumulative: cumulative,
+    );
+  }
+
+  /// 세션 종료 시 누적 통계 업데이트
+  GameStatistics endSession() {
+    return GameStatistics(
+      session: session,
+      cumulative: cumulative.mergeSession(session),
+    );
+  }
+
+  GameStatistics copyWith({
+    SessionStatistics? session,
+    CumulativeStatistics? cumulative,
+  }) {
+    return GameStatistics(
+      session: session ?? this.session,
+      cumulative: cumulative ?? this.cumulative,
+    );
+  }
+
+  /// JSON 직렬화
+  Map<String, dynamic> toJson() {
+    return {
+      'session': session.toJson(),
+      'cumulative': cumulative.toJson(),
+    };
+  }
+
+  /// JSON 역직렬화
+  factory GameStatistics.fromJson(Map<String, dynamic> json) {
+    return GameStatistics(
+      session: SessionStatistics.fromJson(
+        json['session'] as Map<String, dynamic>? ?? {},
+      ),
+      cumulative: CumulativeStatistics.fromJson(
+        json['cumulative'] as Map<String, dynamic>? ?? {},
+      ),
+    );
+  }
+}
+
+/// 세션 통계 (Session Statistics)
+///
+/// 현재 게임 세션의 통계
+class SessionStatistics {
+  const SessionStatistics({
+    required this.playTimeMs,
+    required this.monstersKilled,
+    required this.goldEarned,
+    required this.goldSpent,
+    required this.skillsUsed,
+    required this.criticalHits,
+    required this.maxCriticalStreak,
+    required this.currentCriticalStreak,
+    required this.totalDamageDealt,
+    required this.totalDamageTaken,
+    required this.potionsUsed,
+    required this.itemsSold,
+    required this.questsCompleted,
+    required this.deathCount,
+    required this.bossesDefeated,
+    required this.levelUps,
+  });
+
+  /// 플레이 시간 (밀리초)
+  final int playTimeMs;
+
+  /// 처치한 몬스터 수
+  final int monstersKilled;
+
+  /// 획득한 골드 총량
+  final int goldEarned;
+
+  /// 소비한 골드 총량
+  final int goldSpent;
+
+  /// 사용한 스킬 횟수
+  final int skillsUsed;
+
+  /// 크리티컬 히트 횟수
+  final int criticalHits;
+
+  /// 최대 연속 크리티컬
+  final int maxCriticalStreak;
+
+  /// 현재 연속 크리티컬 (내부 추적용)
+  final int currentCriticalStreak;
+
+  /// 총 입힌 데미지
+  final int totalDamageDealt;
+
+  /// 총 받은 데미지
+  final int totalDamageTaken;
+
+  /// 사용한 물약 수
+  final int potionsUsed;
+
+  /// 판매한 아이템 수
+  final int itemsSold;
+
+  /// 완료한 퀘스트 수
+  final int questsCompleted;
+
+  /// 사망 횟수
+  final int deathCount;
+
+  /// 처치한 보스 수
+  final int bossesDefeated;
+
+  /// 레벨업 횟수
+  final int levelUps;
+
+  /// 플레이 시간 Duration
+  Duration get playTime => Duration(milliseconds: playTimeMs);
+
+  /// 플레이 시간 포맷 (HH:MM:SS)
+  String get formattedPlayTime {
+    final hours = playTime.inHours;
+    final minutes = playTime.inMinutes % 60;
+    final seconds = playTime.inSeconds % 60;
+    return '${hours.toString().padLeft(2, '0')}:'
+        '${minutes.toString().padLeft(2, '0')}:'
+        '${seconds.toString().padLeft(2, '0')}';
+  }
+
+  /// 평균 DPS (damage per second)
+  double get averageDps {
+    if (playTimeMs <= 0) return 0;
+    return totalDamageDealt / (playTimeMs / 1000);
+  }
+
+  /// 킬당 평균 골드
+  double get goldPerKill {
+    if (monstersKilled <= 0) return 0;
+    return goldEarned / monstersKilled;
+  }
+
+  /// 크리티컬 비율
+  double get criticalRate {
+    if (skillsUsed <= 0) return 0;
+    return criticalHits / skillsUsed;
+  }
+
+  /// 빈 세션 통계
+  factory SessionStatistics.empty() => const SessionStatistics(
+    playTimeMs: 0,
+    monstersKilled: 0,
+    goldEarned: 0,
+    goldSpent: 0,
+    skillsUsed: 0,
+    criticalHits: 0,
+    maxCriticalStreak: 0,
+    currentCriticalStreak: 0,
+    totalDamageDealt: 0,
+    totalDamageTaken: 0,
+    potionsUsed: 0,
+    itemsSold: 0,
+    questsCompleted: 0,
+    deathCount: 0,
+    bossesDefeated: 0,
+    levelUps: 0,
+  );
+
+  // ============================================================================
+  // 이벤트 기록 메서드
+  // ============================================================================
+
+  /// 몬스터 처치 기록
+  SessionStatistics recordKill({bool isBoss = false}) {
+    return copyWith(
+      monstersKilled: monstersKilled + 1,
+      bossesDefeated: isBoss ? bossesDefeated + 1 : bossesDefeated,
+    );
+  }
+
+  /// 골드 획득 기록
+  SessionStatistics recordGoldEarned(int amount) {
+    return copyWith(goldEarned: goldEarned + amount);
+  }
+
+  /// 골드 소비 기록
+  SessionStatistics recordGoldSpent(int amount) {
+    return copyWith(goldSpent: goldSpent + amount);
+  }
+
+  /// 스킬 사용 기록
+  SessionStatistics recordSkillUse({required bool isCritical}) {
+    final newCriticalStreak =
+        isCritical ? currentCriticalStreak + 1 : 0;
+    final newMaxStreak = newCriticalStreak > maxCriticalStreak
+        ? newCriticalStreak
+        : maxCriticalStreak;
+
+    return copyWith(
+      skillsUsed: skillsUsed + 1,
+      criticalHits: isCritical ? criticalHits + 1 : criticalHits,
+      currentCriticalStreak: newCriticalStreak,
+      maxCriticalStreak: newMaxStreak,
+    );
+  }
+
+  /// 데미지 기록
+  SessionStatistics recordDamage({
+    int dealt = 0,
+    int taken = 0,
+  }) {
+    return copyWith(
+      totalDamageDealt: totalDamageDealt + dealt,
+      totalDamageTaken: totalDamageTaken + taken,
+    );
+  }
+
+  /// 물약 사용 기록
+  SessionStatistics recordPotionUse() {
+    return copyWith(potionsUsed: potionsUsed + 1);
+  }
+
+  /// 아이템 판매 기록
+  SessionStatistics recordItemSold(int count) {
+    return copyWith(itemsSold: itemsSold + count);
+  }
+
+  /// 퀘스트 완료 기록
+  SessionStatistics recordQuestComplete() {
+    return copyWith(questsCompleted: questsCompleted + 1);
+  }
+
+  /// 사망 기록
+  SessionStatistics recordDeath() {
+    return copyWith(deathCount: deathCount + 1);
+  }
+
+  /// 레벨업 기록
+  SessionStatistics recordLevelUp() {
+    return copyWith(levelUps: levelUps + 1);
+  }
+
+  /// 플레이 시간 업데이트
+  SessionStatistics updatePlayTime(int elapsedMs) {
+    return copyWith(playTimeMs: elapsedMs);
+  }
+
+  SessionStatistics copyWith({
+    int? playTimeMs,
+    int? monstersKilled,
+    int? goldEarned,
+    int? goldSpent,
+    int? skillsUsed,
+    int? criticalHits,
+    int? maxCriticalStreak,
+    int? currentCriticalStreak,
+    int? totalDamageDealt,
+    int? totalDamageTaken,
+    int? potionsUsed,
+    int? itemsSold,
+    int? questsCompleted,
+    int? deathCount,
+    int? bossesDefeated,
+    int? levelUps,
+  }) {
+    return SessionStatistics(
+      playTimeMs: playTimeMs ?? this.playTimeMs,
+      monstersKilled: monstersKilled ?? this.monstersKilled,
+      goldEarned: goldEarned ?? this.goldEarned,
+      goldSpent: goldSpent ?? this.goldSpent,
+      skillsUsed: skillsUsed ?? this.skillsUsed,
+      criticalHits: criticalHits ?? this.criticalHits,
+      maxCriticalStreak: maxCriticalStreak ?? this.maxCriticalStreak,
+      currentCriticalStreak:
+          currentCriticalStreak ?? this.currentCriticalStreak,
+      totalDamageDealt: totalDamageDealt ?? this.totalDamageDealt,
+      totalDamageTaken: totalDamageTaken ?? this.totalDamageTaken,
+      potionsUsed: potionsUsed ?? this.potionsUsed,
+      itemsSold: itemsSold ?? this.itemsSold,
+      questsCompleted: questsCompleted ?? this.questsCompleted,
+      deathCount: deathCount ?? this.deathCount,
+      bossesDefeated: bossesDefeated ?? this.bossesDefeated,
+      levelUps: levelUps ?? this.levelUps,
+    );
+  }
+
+  /// JSON 직렬화
+  Map<String, dynamic> toJson() {
+    return {
+      'playTimeMs': playTimeMs,
+      'monstersKilled': monstersKilled,
+      'goldEarned': goldEarned,
+      'goldSpent': goldSpent,
+      'skillsUsed': skillsUsed,
+      'criticalHits': criticalHits,
+      'maxCriticalStreak': maxCriticalStreak,
+      'totalDamageDealt': totalDamageDealt,
+      'totalDamageTaken': totalDamageTaken,
+      'potionsUsed': potionsUsed,
+      'itemsSold': itemsSold,
+      'questsCompleted': questsCompleted,
+      'deathCount': deathCount,
+      'bossesDefeated': bossesDefeated,
+      'levelUps': levelUps,
+    };
+  }
+
+  /// JSON 역직렬화
+  factory SessionStatistics.fromJson(Map<String, dynamic> json) {
+    return SessionStatistics(
+      playTimeMs: json['playTimeMs'] as int? ?? 0,
+      monstersKilled: json['monstersKilled'] as int? ?? 0,
+      goldEarned: json['goldEarned'] as int? ?? 0,
+      goldSpent: json['goldSpent'] as int? ?? 0,
+      skillsUsed: json['skillsUsed'] as int? ?? 0,
+      criticalHits: json['criticalHits'] as int? ?? 0,
+      maxCriticalStreak: json['maxCriticalStreak'] as int? ?? 0,
+      currentCriticalStreak: 0, // 세션간 유지 안 함
+      totalDamageDealt: json['totalDamageDealt'] as int? ?? 0,
+      totalDamageTaken: json['totalDamageTaken'] as int? ?? 0,
+      potionsUsed: json['potionsUsed'] as int? ?? 0,
+      itemsSold: json['itemsSold'] as int? ?? 0,
+      questsCompleted: json['questsCompleted'] as int? ?? 0,
+      deathCount: json['deathCount'] as int? ?? 0,
+      bossesDefeated: json['bossesDefeated'] as int? ?? 0,
+      levelUps: json['levelUps'] as int? ?? 0,
+    );
+  }
+}
+
+/// 누적 통계 (Cumulative Statistics)
+///
+/// 모든 게임 세션의 누적 통계
+class CumulativeStatistics {
+  const CumulativeStatistics({
+    required this.totalPlayTimeMs,
+    required this.totalMonstersKilled,
+    required this.totalGoldEarned,
+    required this.totalGoldSpent,
+    required this.totalSkillsUsed,
+    required this.totalCriticalHits,
+    required this.bestCriticalStreak,
+    required this.totalDamageDealt,
+    required this.totalDamageTaken,
+    required this.totalPotionsUsed,
+    required this.totalItemsSold,
+    required this.totalQuestsCompleted,
+    required this.totalDeaths,
+    required this.totalBossesDefeated,
+    required this.totalLevelUps,
+    required this.highestLevel,
+    required this.highestGoldHeld,
+    required this.gamesCompleted,
+    required this.gamesStarted,
+  });
+
+  /// 총 플레이 시간 (밀리초)
+  final int totalPlayTimeMs;
+
+  /// 총 처치한 몬스터 수
+  final int totalMonstersKilled;
+
+  /// 총 획득한 골드
+  final int totalGoldEarned;
+
+  /// 총 소비한 골드
+  final int totalGoldSpent;
+
+  /// 총 스킬 사용 횟수
+  final int totalSkillsUsed;
+
+  /// 총 크리티컬 히트 횟수
+  final int totalCriticalHits;
+
+  /// 최고 연속 크리티컬
+  final int bestCriticalStreak;
+
+  /// 총 입힌 데미지
+  final int totalDamageDealt;
+
+  /// 총 받은 데미지
+  final int totalDamageTaken;
+
+  /// 총 사용한 물약 수
+  final int totalPotionsUsed;
+
+  /// 총 판매한 아이템 수
+  final int totalItemsSold;
+
+  /// 총 완료한 퀘스트 수
+  final int totalQuestsCompleted;
+
+  /// 총 사망 횟수
+  final int totalDeaths;
+
+  /// 총 처치한 보스 수
+  final int totalBossesDefeated;
+
+  /// 총 레벨업 횟수
+  final int totalLevelUps;
+
+  /// 최고 달성 레벨
+  final int highestLevel;
+
+  /// 최대 보유 골드
+  final int highestGoldHeld;
+
+  /// 클리어한 게임 수
+  final int gamesCompleted;
+
+  /// 시작한 게임 수
+  final int gamesStarted;
+
+  /// 총 플레이 시간 Duration
+  Duration get totalPlayTime => Duration(milliseconds: totalPlayTimeMs);
+
+  /// 총 플레이 시간 포맷 (HH:MM:SS)
+  String get formattedTotalPlayTime {
+    final hours = totalPlayTime.inHours;
+    final minutes = totalPlayTime.inMinutes % 60;
+    final seconds = totalPlayTime.inSeconds % 60;
+    return '${hours.toString().padLeft(2, '0')}:'
+        '${minutes.toString().padLeft(2, '0')}:'
+        '${seconds.toString().padLeft(2, '0')}';
+  }
+
+  /// 평균 게임당 플레이 시간
+  Duration get averagePlayTimePerGame {
+    if (gamesStarted <= 0) return Duration.zero;
+    return Duration(milliseconds: totalPlayTimeMs ~/ gamesStarted);
+  }
+
+  /// 게임 완료율
+  double get completionRate {
+    if (gamesStarted <= 0) return 0;
+    return gamesCompleted / gamesStarted;
+  }
+
+  /// 빈 누적 통계
+  factory CumulativeStatistics.empty() => const CumulativeStatistics(
+    totalPlayTimeMs: 0,
+    totalMonstersKilled: 0,
+    totalGoldEarned: 0,
+    totalGoldSpent: 0,
+    totalSkillsUsed: 0,
+    totalCriticalHits: 0,
+    bestCriticalStreak: 0,
+    totalDamageDealt: 0,
+    totalDamageTaken: 0,
+    totalPotionsUsed: 0,
+    totalItemsSold: 0,
+    totalQuestsCompleted: 0,
+    totalDeaths: 0,
+    totalBossesDefeated: 0,
+    totalLevelUps: 0,
+    highestLevel: 0,
+    highestGoldHeld: 0,
+    gamesCompleted: 0,
+    gamesStarted: 0,
+  );
+
+  /// 세션 통계 병합
+  CumulativeStatistics mergeSession(SessionStatistics session) {
+    return CumulativeStatistics(
+      totalPlayTimeMs: totalPlayTimeMs + session.playTimeMs,
+      totalMonstersKilled: totalMonstersKilled + session.monstersKilled,
+      totalGoldEarned: totalGoldEarned + session.goldEarned,
+      totalGoldSpent: totalGoldSpent + session.goldSpent,
+      totalSkillsUsed: totalSkillsUsed + session.skillsUsed,
+      totalCriticalHits: totalCriticalHits + session.criticalHits,
+      bestCriticalStreak: session.maxCriticalStreak > bestCriticalStreak
+          ? session.maxCriticalStreak
+          : bestCriticalStreak,
+      totalDamageDealt: totalDamageDealt + session.totalDamageDealt,
+      totalDamageTaken: totalDamageTaken + session.totalDamageTaken,
+      totalPotionsUsed: totalPotionsUsed + session.potionsUsed,
+      totalItemsSold: totalItemsSold + session.itemsSold,
+      totalQuestsCompleted: totalQuestsCompleted + session.questsCompleted,
+      totalDeaths: totalDeaths + session.deathCount,
+      totalBossesDefeated: totalBossesDefeated + session.bossesDefeated,
+      totalLevelUps: totalLevelUps + session.levelUps,
+      highestLevel: highestLevel, // 별도 업데이트 필요
+      highestGoldHeld: highestGoldHeld, // 별도 업데이트 필요
+      gamesCompleted: gamesCompleted, // 별도 업데이트 필요
+      gamesStarted: gamesStarted, // 별도 업데이트 필요
+    );
+  }
+
+  /// 최고 레벨 업데이트
+  CumulativeStatistics updateHighestLevel(int level) {
+    if (level <= highestLevel) return this;
+    return copyWith(highestLevel: level);
+  }
+
+  /// 최대 골드 업데이트
+  CumulativeStatistics updateHighestGold(int gold) {
+    if (gold <= highestGoldHeld) return this;
+    return copyWith(highestGoldHeld: gold);
+  }
+
+  /// 새 게임 시작 기록
+  CumulativeStatistics recordGameStart() {
+    return copyWith(gamesStarted: gamesStarted + 1);
+  }
+
+  /// 게임 클리어 기록
+  CumulativeStatistics recordGameComplete() {
+    return copyWith(gamesCompleted: gamesCompleted + 1);
+  }
+
+  CumulativeStatistics copyWith({
+    int? totalPlayTimeMs,
+    int? totalMonstersKilled,
+    int? totalGoldEarned,
+    int? totalGoldSpent,
+    int? totalSkillsUsed,
+    int? totalCriticalHits,
+    int? bestCriticalStreak,
+    int? totalDamageDealt,
+    int? totalDamageTaken,
+    int? totalPotionsUsed,
+    int? totalItemsSold,
+    int? totalQuestsCompleted,
+    int? totalDeaths,
+    int? totalBossesDefeated,
+    int? totalLevelUps,
+    int? highestLevel,
+    int? highestGoldHeld,
+    int? gamesCompleted,
+    int? gamesStarted,
+  }) {
+    return CumulativeStatistics(
+      totalPlayTimeMs: totalPlayTimeMs ?? this.totalPlayTimeMs,
+      totalMonstersKilled: totalMonstersKilled ?? this.totalMonstersKilled,
+      totalGoldEarned: totalGoldEarned ?? this.totalGoldEarned,
+      totalGoldSpent: totalGoldSpent ?? this.totalGoldSpent,
+      totalSkillsUsed: totalSkillsUsed ?? this.totalSkillsUsed,
+      totalCriticalHits: totalCriticalHits ?? this.totalCriticalHits,
+      bestCriticalStreak: bestCriticalStreak ?? this.bestCriticalStreak,
+      totalDamageDealt: totalDamageDealt ?? this.totalDamageDealt,
+      totalDamageTaken: totalDamageTaken ?? this.totalDamageTaken,
+      totalPotionsUsed: totalPotionsUsed ?? this.totalPotionsUsed,
+      totalItemsSold: totalItemsSold ?? this.totalItemsSold,
+      totalQuestsCompleted: totalQuestsCompleted ?? this.totalQuestsCompleted,
+      totalDeaths: totalDeaths ?? this.totalDeaths,
+      totalBossesDefeated: totalBossesDefeated ?? this.totalBossesDefeated,
+      totalLevelUps: totalLevelUps ?? this.totalLevelUps,
+      highestLevel: highestLevel ?? this.highestLevel,
+      highestGoldHeld: highestGoldHeld ?? this.highestGoldHeld,
+      gamesCompleted: gamesCompleted ?? this.gamesCompleted,
+      gamesStarted: gamesStarted ?? this.gamesStarted,
+    );
+  }
+
+  /// JSON 직렬화
+  Map<String, dynamic> toJson() {
+    return {
+      'totalPlayTimeMs': totalPlayTimeMs,
+      'totalMonstersKilled': totalMonstersKilled,
+      'totalGoldEarned': totalGoldEarned,
+      'totalGoldSpent': totalGoldSpent,
+      'totalSkillsUsed': totalSkillsUsed,
+      'totalCriticalHits': totalCriticalHits,
+      'bestCriticalStreak': bestCriticalStreak,
+      'totalDamageDealt': totalDamageDealt,
+      'totalDamageTaken': totalDamageTaken,
+      'totalPotionsUsed': totalPotionsUsed,
+      'totalItemsSold': totalItemsSold,
+      'totalQuestsCompleted': totalQuestsCompleted,
+      'totalDeaths': totalDeaths,
+      'totalBossesDefeated': totalBossesDefeated,
+      'totalLevelUps': totalLevelUps,
+      'highestLevel': highestLevel,
+      'highestGoldHeld': highestGoldHeld,
+      'gamesCompleted': gamesCompleted,
+      'gamesStarted': gamesStarted,
+    };
+  }
+
+  /// JSON 역직렬화
+  factory CumulativeStatistics.fromJson(Map<String, dynamic> json) {
+    return CumulativeStatistics(
+      totalPlayTimeMs: json['totalPlayTimeMs'] as int? ?? 0,
+      totalMonstersKilled: json['totalMonstersKilled'] as int? ?? 0,
+      totalGoldEarned: json['totalGoldEarned'] as int? ?? 0,
+      totalGoldSpent: json['totalGoldSpent'] as int? ?? 0,
+      totalSkillsUsed: json['totalSkillsUsed'] as int? ?? 0,
+      totalCriticalHits: json['totalCriticalHits'] as int? ?? 0,
+      bestCriticalStreak: json['bestCriticalStreak'] as int? ?? 0,
+      totalDamageDealt: json['totalDamageDealt'] as int? ?? 0,
+      totalDamageTaken: json['totalDamageTaken'] as int? ?? 0,
+      totalPotionsUsed: json['totalPotionsUsed'] as int? ?? 0,
+      totalItemsSold: json['totalItemsSold'] as int? ?? 0,
+      totalQuestsCompleted: json['totalQuestsCompleted'] as int? ?? 0,
+      totalDeaths: json['totalDeaths'] as int? ?? 0,
+      totalBossesDefeated: json['totalBossesDefeated'] as int? ?? 0,
+      totalLevelUps: json['totalLevelUps'] as int? ?? 0,
+      highestLevel: json['highestLevel'] as int? ?? 0,
+      highestGoldHeld: json['highestGoldHeld'] as int? ?? 0,
+      gamesCompleted: json['gamesCompleted'] as int? ?? 0,
+      gamesStarted: json['gamesStarted'] as int? ?? 0,
+    );
+  }
+}

lib/src/core/storage/statistics_storage.dart

@@ -0,0 +1,126 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:askiineverdie/src/core/model/game_statistics.dart';
+import 'package:path_provider/path_provider.dart';
+
+/// 게임 통계 저장소 (Statistics Storage)
+///
+/// 누적 통계 데이터 저장/로드 관리
+class StatisticsStorage {
+  StatisticsStorage();
+
+  static const String _fileName = 'game_statistics.json';
+
+  Directory? _storageDir;
+
+  Future<Directory> _getStorageDir() async {
+    if (_storageDir != null) return _storageDir!;
+    _storageDir = await getApplicationSupportDirectory();
+    return _storageDir!;
+  }
+
+  File _getFile(Directory dir) {
+    return File('${dir.path}/$_fileName');
+  }
+
+  /// 누적 통계 로드
+  Future<CumulativeStatistics> loadCumulative() async {
+    try {
+      final dir = await _getStorageDir();
+      final file = _getFile(dir);
+
+      if (!await file.exists()) {
+        return CumulativeStatistics.empty();
+      }
+
+      final content = await file.readAsString();
+      final json = jsonDecode(content) as Map<String, dynamic>;
+
+      // cumulative 키가 있으면 해당 데이터 사용
+      if (json.containsKey('cumulative')) {
+        return CumulativeStatistics.fromJson(
+          json['cumulative'] as Map<String, dynamic>,
+        );
+      }
+
+      // 직접 CumulativeStatistics JSON인 경우
+      return CumulativeStatistics.fromJson(json);
+    } catch (e) {
+      // 파일이 없거나 손상된 경우 빈 통계 반환
+      return CumulativeStatistics.empty();
+    }
+  }
+
+  /// 누적 통계 저장
+  Future<bool> saveCumulative(CumulativeStatistics stats) async {
+    try {
+      final dir = await _getStorageDir();
+      final file = _getFile(dir);
+
+      final json = {
+        'version': 1,
+        'lastUpdated': DateTime.now().toIso8601String(),
+        'cumulative': stats.toJson(),
+      };
+
+      final content = const JsonEncoder.withIndent('  ').convert(json);
+      await file.writeAsString(content);
+      return true;
+    } catch (e) {
+      return false;
+    }
+  }
+
+  /// 세션 종료 시 누적 통계 업데이트
+  Future<bool> mergeSession(SessionStatistics session) async {
+    final current = await loadCumulative();
+    final updated = current.mergeSession(session);
+    return saveCumulative(updated);
+  }
+
+  /// 최고 레벨 업데이트
+  Future<bool> updateHighestLevel(int level) async {
+    final current = await loadCumulative();
+    if (level <= current.highestLevel) return true;
+    final updated = current.updateHighestLevel(level);
+    return saveCumulative(updated);
+  }
+
+  /// 최대 골드 업데이트
+  Future<bool> updateHighestGold(int gold) async {
+    final current = await loadCumulative();
+    if (gold <= current.highestGoldHeld) return true;
+    final updated = current.updateHighestGold(gold);
+    return saveCumulative(updated);
+  }
+
+  /// 새 게임 시작 기록
+  Future<bool> recordGameStart() async {
+    final current = await loadCumulative();
+    final updated = current.recordGameStart();
+    return saveCumulative(updated);
+  }
+
+  /// 게임 클리어 기록
+  Future<bool> recordGameComplete() async {
+    final current = await loadCumulative();
+    final updated = current.recordGameComplete();
+    return saveCumulative(updated);
+  }
+
+  /// 통계 초기화 (테스트용)
+  Future<bool> clear() async {
+    try {
+      final dir = await _getStorageDir();
+      final file = _getFile(dir);
+
+      if (await file.exists()) {
+        await file.delete();
+      }
+      return true;
+    } catch (e) {
+      return false;
+    }
+  }
+}

lib/src/core/util/balance_constants.dart

@@ -10,27 +10,42 @@ class ExpConstants {
   /// 기본 경험치 값
   static const int baseExp = 100;
 
-  /// 레벨당 경험치 증가율 (1.15 = 15% 증가)
-  static const double expGrowthRate = 1.15;
-
-  /// 레벨업에 필요한 경험치 계산
-  ///
-  /// 공식: baseExp * (expGrowthRate ^ level)
-  /// 레벨 10: ~405 exp
-  /// 레벨 50: ~108,366 exp
-  /// 레벨 100: ~11,739,085 exp
-  static int requiredExp(int level) {
-    if (level <= 0) return baseExp;
-    return (baseExp * _pow(expGrowthRate, level)).round();
+  /// 레벨 구간별 경험치 증가율 (tiered growth rate)
+  /// - 1-30: 1.10 (초반 빠른 진행)
+  /// - 31-60: 1.12 (중반 적정 속도)
+  /// - 61-100: 1.14 (후반 도전)
+  static double _getGrowthRate(int level) {
+    if (level <= 30) return 1.10;
+    if (level <= 60) return 1.12;
+    return 1.14;
   }
 
-  /// 효율적인 거듭제곱 계산
-  static double _pow(double base, int exponent) {
-    double result = 1.0;
-    for (int i = 0; i < exponent; i++) {
-      result *= base;
+  /// 레벨업에 필요한 경험치 계산 (구간별 차등 적용)
+  ///
+  /// 조정 후 예상:
+  /// 레벨 10: ~259 exp
+  /// 레벨 30: ~1,744 exp
+  /// 레벨 50: ~9,705 exp
+  /// 레벨 80: ~133,860 exp
+  /// 레벨 100: ~636,840 exp
+  static int requiredExp(int level) {
+    if (level <= 0) return baseExp;
+
+    // 구간별 복합 성장 계산
+    double result = baseExp.toDouble();
+    for (int i = 1; i <= level; i++) {
+      result *= _getGrowthRate(i);
     }
-    return result;
+    return result.round();
+  }
+
+  /// 총 누적 경험치 계산 (특정 레벨까지)
+  static int totalExpToLevel(int level) {
+    int total = 0;
+    for (int i = 1; i < level; i++) {
+      total += requiredExp(i);
+    }
+    return total;
   }
 }
 
@@ -88,40 +103,40 @@ class MonsterTypeMultiplier {
     gold: 1.0,
   );
 
-  /// 정예: HP 2배, ATK 1.3배, DEF 1.2배, 보상 2배
+  /// 정예: HP 2배, ATK 1.3배, DEF 1.2배, EXP 3배 (상향), GOLD 2.5배
   static const elite = MonsterTypeMultiplier(
     hp: 2.0,
     atk: 1.3,
     def: 1.2,
-    exp: 2.0,
-    gold: 2.0,
+    exp: 3.0, // 2.0 → 3.0 상향
+    gold: 2.5,
   );
 
-  /// 미니보스: HP 5배, ATK/DEF 1.5배, 보상 5배
+  /// 미니보스: HP 5배, ATK/DEF 1.5배, EXP 8배 (상향), GOLD 6배
   static const miniboss = MonsterTypeMultiplier(
     hp: 5.0,
     atk: 1.5,
     def: 1.5,
-    exp: 5.0,
-    gold: 5.0,
+    exp: 8.0, // 5.0 → 8.0 상향
+    gold: 6.0,
   );
 
-  /// 보스: HP 10배, ATK/DEF 2배, EXP 15배, GOLD 10배
+  /// 보스: HP 8배 (하향), ATK/DEF 1.8배 (하향), EXP 25배 (상향), GOLD 15배
   static const boss = MonsterTypeMultiplier(
-    hp: 10.0,
-    atk: 2.0,
-    def: 2.0,
-    exp: 15.0,
-    gold: 10.0,
+    hp: 8.0, // 10.0 → 8.0 하향 (플레이어 접근성 개선)
+    atk: 1.8, // 2.0 → 1.8 하향
+    def: 1.8, // 2.0 → 1.8 하향
+    exp: 25.0, // 15.0 → 25.0 상향
+    gold: 15.0,
   );
 
-  /// 최종 보스: HP 20배, ATK/DEF 2.5배, EXP 50배, GOLD 30배
+  /// 최종 보스: HP 12배 (하향), ATK/DEF 2.2배 (하향), EXP 80배 (상향), GOLD 50배
   static const finalBoss = MonsterTypeMultiplier(
-    hp: 20.0,
-    atk: 2.5,
-    def: 2.5,
-    exp: 50.0,
-    gold: 30.0,
+    hp: 12.0, // 20.0 → 12.0 대폭 하향 (클리어 가능성 확보)
+    atk: 2.2, // 2.5 → 2.2 하향
+    def: 2.2, // 2.5 → 2.2 하향
+    exp: 80.0, // 50.0 → 80.0 상향
+    gold: 50.0,
   );
 }
 
@@ -283,6 +298,8 @@ class BossStats extends MonsterBaseStats {
   }
 
   /// Kernel Panic Archon (Act IV 보스, 레벨 80)
+  ///
+  /// Phase 6 밸런스 조정: enrageMultiplier 1.6 → 1.5
   static BossStats kernelPanicArchon(int baseLevel) {
     final base = MonsterBaseStats.generate(baseLevel, MonsterType.boss);
     return BossStats(
@@ -293,7 +310,7 @@ class BossStats extends MonsterBaseStats {
       gold: base.gold,
       phases: 3,
       enrageThreshold: 0.2,
-      enrageMultiplier: 1.6,
+      enrageMultiplier: 1.5, // 1.6 → 1.5 (분노 시 50% 스탯 증가)
       hasShield: true,
       shieldAmount: (base.hp * 0.2).round(),
       abilities: [BossAbilityType.stunAttack],
@@ -301,6 +318,11 @@ class BossStats extends MonsterBaseStats {
   }
 
   /// Glitch God (최종 보스, 레벨 100)
+  ///
+  /// Phase 6 밸런스 조정:
+  /// - enrageThreshold: 0.1 → 0.15 (분노 발동 시점 완화)
+  /// - enrageMultiplier: 2.0 → 1.7 (분노 시 스탯 증가 완화)
+  /// - shieldAmount: 50% → 35% (보호막 감소)
   static BossStats glitchGod(int baseLevel) {
     final base = MonsterBaseStats.generate(baseLevel, MonsterType.finalBoss);
     return BossStats(
@@ -310,10 +332,10 @@ class BossStats extends MonsterBaseStats {
       exp: base.exp,
       gold: base.gold,
       phases: 5,
-      enrageThreshold: 0.1,
-      enrageMultiplier: 2.0,
+      enrageThreshold: 0.15, // 0.1 → 0.15 (15% HP에서 분노)
+      enrageMultiplier: 1.7, // 2.0 → 1.7 (분노 시 70% 스탯 증가)
       hasShield: true,
-      shieldAmount: (base.hp * 0.5).round(),
+      shieldAmount: (base.hp * 0.35).round(), // 0.5 → 0.35 (보호막 30% 감소)
       abilities: [
         BossAbilityType.phaseShift,
         BossAbilityType.multiAttack,
@@ -398,11 +420,17 @@ class LevelTierSettings {
 class PlayerScaling {
   PlayerScaling._();
 
-  /// 레벨당 HP 증가량
-  static const int hpPerLevel = 10;
+  /// 레벨당 HP 증가량 (10 → 12 상향)
+  static const int hpPerLevel = 12;
 
-  /// 레벨당 MP 증가량
-  static const int mpPerLevel = 5;
+  /// 레벨당 MP 증가량 (5 → 6 상향)
+  static const int mpPerLevel = 6;
+
+  /// CON당 HP 보너스 (5 → 6 상향)
+  static const int hpPerCon = 6;
+
+  /// INT당 MP 보너스 (3 → 4 상향)
+  static const int mpPerInt = 4;
 
   /// 레벨업 시 HP/MP 계산
   static ({int hpMax, int mpMax}) calculateResources({
@@ -412,8 +440,17 @@ class PlayerScaling {
     required int conBonus,
     required int intBonus,
   }) {
-    final hpMax = baseHp + (level - 1) * hpPerLevel + conBonus * 5;
-    final mpMax = baseMp + (level - 1) * mpPerLevel + intBonus * 3;
+    final hpMax = baseHp + (level - 1) * hpPerLevel + conBonus * hpPerCon;
+    final mpMax = baseMp + (level - 1) * mpPerLevel + intBonus * mpPerInt;
     return (hpMax: hpMax, mpMax: mpMax);
   }
+
+  /// 레벨 구간별 ATK 보너스 (후반 DPS 보조)
+  /// - 레벨 60+: +1 ATK per level
+  /// - 레벨 80+: +2 ATK per level
+  static int bonusAtk(int level) {
+    if (level >= 80) return (level - 80) * 2 + 20;
+    if (level >= 60) return level - 60;
+    return 0;
+  }
 }

lib/src/features/game/game_play_screen.dart

@@ -32,7 +32,10 @@ import 'package:askiineverdie/src/features/game/widgets/task_progress_panel.dart
 import 'package:askiineverdie/src/features/game/widgets/active_buff_panel.dart';
 import 'package:askiineverdie/src/features/game/layouts/mobile_carousel_layout.dart';
 import 'package:askiineverdie/src/features/settings/settings_screen.dart';
+import 'package:askiineverdie/src/features/game/widgets/statistics_dialog.dart';
+import 'package:askiineverdie/src/features/game/widgets/help_dialog.dart';
 import 'package:askiineverdie/src/core/storage/settings_repository.dart';
+import 'package:askiineverdie/src/core/audio/audio_service.dart';
 
 /// 게임 진행 화면 (Main.dfm 기반 3패널 레이아웃)
 ///
@@ -41,6 +44,7 @@ class GamePlayScreen extends StatefulWidget {
   const GamePlayScreen({
     super.key,
     required this.controller,
+    this.audioService,
     this.forceCarouselLayout = false,
     this.forceDesktopLayout = false,
     this.onThemeModeChange,
@@ -49,6 +53,9 @@ class GamePlayScreen extends StatefulWidget {
 
   final GameSessionController controller;
 
+  /// 오디오 서비스 (BGM/SFX 재생)
+  final AudioService? audioService;
+
   /// 테스트 모드: 웹에서도 모바일 캐로셀 레이아웃 강제 사용
   final bool forceCarouselLayout;
 
@@ -89,6 +96,13 @@ class _GamePlayScreenState extends State<GamePlayScreen>
   // 전투 이벤트 추적 (마지막 처리된 이벤트 수)
   int _lastProcessedEventCount = 0;
 
+  // 오디오 상태 추적
+  bool _wasInCombat = false;
+
+  // 사운드 볼륨 상태 (모바일 설정 UI용)
+  double _bgmVolume = 0.7;
+  double _sfxVolume = 0.8;
+
   void _checkSpecialEvents(GameState state) {
     // Phase 8: 태스크 변경 시 로그 추가
     final currentCaption = state.progress.currentTask.caption;
@@ -102,6 +116,9 @@ class _GamePlayScreenState extends State<GamePlayScreen>
     // 전투 이벤트 처리 (Combat Events)
     _processCombatEvents(state);
 
+    // 오디오: 전투 상태 변경 시 BGM 전환
+    _updateBgmForCombatState(state);
+
     // 레벨업 감지
     if (state.traits.level > _lastLevel && _lastLevel > 0) {
       _specialAnimation = AsciiAnimationType.levelUp;
@@ -110,6 +127,8 @@ class _GamePlayScreenState extends State<GamePlayScreen>
         '${game_l10n.uiLevelUp} Lv.${state.traits.level}',
         CombatLogType.levelUp,
       );
+      // 오디오: 레벨업 SFX
+      widget.audioService?.playSfx('level_up');
       _resetSpecialAnimationAfterFrame();
 
       // Phase 9: Act 변경 감지 (레벨 기반)
@@ -147,6 +166,8 @@ class _GamePlayScreenState extends State<GamePlayScreen>
           CombatLogType.questComplete,
         );
       }
+      // 오디오: 퀘스트 완료 SFX
+      widget.audioService?.playSfx('quest_complete');
       _resetSpecialAnimationAfterFrame();
     }
     _lastQuestCount = state.progress.questCount;
@@ -192,11 +213,74 @@ class _GamePlayScreenState extends State<GamePlayScreen>
     for (final event in newEvents) {
       final (message, type) = _formatCombatEvent(event);
       _addCombatLog(message, type);
+
+      // 오디오: 전투 이벤트에 따른 SFX 재생
+      _playCombatEventSfx(event);
     }
 
     _lastProcessedEventCount = events.length;
   }
 
+  /// 전투 상태에 따른 BGM 전환
+  void _updateBgmForCombatState(GameState state) {
+    final audio = widget.audioService;
+    if (audio == null) return;
+
+    final combat = state.progress.currentCombat;
+    final isInCombat = combat != null && combat.isActive;
+
+    if (isInCombat && !_wasInCombat) {
+      // 전투 시작: 보스 여부에 따라 BGM 선택
+      // 몬스터 레벨이 플레이어보다 5 이상 높으면 보스로 간주
+      final monsterLevel = state.progress.currentTask.monsterLevel ?? 0;
+      final playerLevel = state.traits.level;
+      final isBoss = monsterLevel >= playerLevel + 5;
+
+      if (isBoss) {
+        audio.playBgm('boss');
+      } else {
+        audio.playBgm('battle');
+      }
+    } else if (!isInCombat && _wasInCombat) {
+      // 전투 종료: 마을 BGM으로 복귀
+      audio.playBgm('town');
+    }
+
+    _wasInCombat = isInCombat;
+  }
+
+  /// 전투 이벤트에 따른 SFX 재생
+  void _playCombatEventSfx(CombatEvent event) {
+    final audio = widget.audioService;
+    if (audio == null) return;
+
+    switch (event.type) {
+      case CombatEventType.playerAttack:
+        audio.playSfx('attack');
+      case CombatEventType.monsterAttack:
+        audio.playSfx('hit');
+      case CombatEventType.playerSkill:
+        audio.playSfx('skill');
+      case CombatEventType.playerHeal:
+      case CombatEventType.playerPotion:
+        audio.playSfx('item');
+      case CombatEventType.potionDrop:
+        audio.playSfx('item');
+      case CombatEventType.playerBuff:
+      case CombatEventType.playerDebuff:
+        audio.playSfx('skill');
+      case CombatEventType.dotTick:
+        // DOT 틱은 SFX 없음 (너무 자주 발생)
+        break;
+      case CombatEventType.playerEvade:
+      case CombatEventType.monsterEvade:
+      case CombatEventType.playerBlock:
+      case CombatEventType.playerParry:
+        // 회피/방어는 별도 SFX 없음
+        break;
+    }
+  }
+
   /// 전투 이벤트를 메시지와 타입으로 변환
   (String, CombatLogType) _formatCombatEvent(CombatEvent event) {
     final target = event.targetName ?? '';
@@ -256,6 +340,10 @@ class _GamePlayScreenState extends State<GamePlayScreen>
         game_l10n.combatBuffActivated(skillName),
         CombatLogType.buff,
       ),
+      CombatEventType.playerDebuff => (
+        game_l10n.combatDebuffApplied(skillName, target),
+        CombatLogType.debuff,
+      ),
       CombatEventType.dotTick => (
         game_l10n.combatDotTick(skillName, event.damage),
         CombatLogType.dotTick,
@@ -361,6 +449,29 @@ class _GamePlayScreenState extends State<GamePlayScreen>
       _lastQuestCount = state.progress.questCount;
       _lastPlotStageCount = state.progress.plotStageCount;
       _lastAct = getActForLevel(state.traits.level);
+
+      // 초기 전투 상태 확인
+      final combat = state.progress.currentCombat;
+      _wasInCombat = combat != null && combat.isActive;
+    }
+
+    // 누적 통계 로드
+    widget.controller.loadCumulativeStats();
+
+    // 초기 BGM 재생 (마을 테마)
+    widget.audioService?.playBgm('town');
+
+    // 오디오 볼륨 초기화
+    _initAudioVolumes();
+  }
+
+  /// 오디오 볼륨 초기화 (설정에서 로드)
+  Future<void> _initAudioVolumes() async {
+    final audio = widget.audioService;
+    if (audio != null) {
+      _bgmVolume = audio.bgmVolume;
+      _sfxVolume = audio.sfxVolume;
+      if (mounted) setState(() {});
     }
   }
 
@@ -465,6 +576,15 @@ class _GamePlayScreenState extends State<GamePlayScreen>
     return platform == TargetPlatform.iOS || platform == TargetPlatform.android;
   }
 
+  /// 통계 다이얼로그 표시
+  void _showStatisticsDialog(BuildContext context) {
+    StatisticsDialog.show(
+      context,
+      session: widget.controller.sessionStats,
+      cumulative: widget.controller.cumulativeStats,
+    );
+  }
+
   /// 설정 화면 표시
   void _showSettingsScreen(BuildContext context) {
     final settingsRepo = SettingsRepository();
@@ -614,6 +734,17 @@ class _GamePlayScreenState extends State<GamePlayScreen>
                 },
                 currentThemeMode: widget.currentThemeMode,
                 onThemeModeChange: widget.onThemeModeChange,
+                // 사운드 설정
+                bgmVolume: _bgmVolume,
+                sfxVolume: _sfxVolume,
+                onBgmVolumeChange: (volume) {
+                  setState(() => _bgmVolume = volume);
+                  widget.audioService?.setBgmVolume(volume);
+                },
+                onSfxVolumeChange: (volume) {
+                  setState(() => _sfxVolume = volume);
+                  widget.audioService?.setSfxVolume(volume);
+                },
               ),
               // 사망 오버레이
               if (state.isDead && state.deathInfo != null)
@@ -666,6 +797,18 @@ class _GamePlayScreenState extends State<GamePlayScreen>
                   onPressed: () => widget.controller.loop?.cheatCompletePlot(),
                 ),
               ],
+              // 통계 버튼
+              IconButton(
+                icon: const Icon(Icons.bar_chart),
+                tooltip: game_l10n.uiStatistics,
+                onPressed: () => _showStatisticsDialog(context),
+              ),
+              // 도움말 버튼
+              IconButton(
+                icon: const Icon(Icons.help_outline),
+                tooltip: game_l10n.uiHelp,
+                onPressed: () => HelpDialog.show(context),
+              ),
               // 설정 버튼
               IconButton(
                 icon: const Icon(Icons.settings),

lib/src/features/game/game_session_controller.dart

@@ -5,7 +5,9 @@ import 'package:askiineverdie/src/core/engine/progress_service.dart';
 import 'package:askiineverdie/src/core/engine/resurrection_service.dart';
 import 'package:askiineverdie/src/core/engine/shop_service.dart';
 import 'package:askiineverdie/src/core/model/game_state.dart';
+import 'package:askiineverdie/src/core/model/game_statistics.dart';
 import 'package:askiineverdie/src/core/storage/save_manager.dart';
+import 'package:askiineverdie/src/core/storage/statistics_storage.dart';
 import 'package:flutter/foundation.dart';
 
 enum GameSessionStatus { idle, loading, running, error, dead }
@@ -18,12 +20,15 @@ class GameSessionController extends ChangeNotifier {
     this.autoSaveConfig = const AutoSaveConfig(),
     Duration tickInterval = const Duration(milliseconds: 50),
     DateTime Function()? now,
+    StatisticsStorage? statisticsStorage,
   }) : _tickInterval = tickInterval,
-       _now = now ?? DateTime.now;
+       _now = now ?? DateTime.now,
+       _statisticsStorage = statisticsStorage ?? StatisticsStorage();
 
   final ProgressService progressService;
   final SaveManager saveManager;
   final AutoSaveConfig autoSaveConfig;
+  final StatisticsStorage _statisticsStorage;
 
   final Duration _tickInterval;
   final DateTime Function() _now;
@@ -36,12 +41,26 @@ class GameSessionController extends ChangeNotifier {
   GameState? _state;
   String? _error;
 
+  // 통계 관련 필드
+  SessionStatistics _sessionStats = SessionStatistics.empty();
+  CumulativeStatistics _cumulativeStats = CumulativeStatistics.empty();
+  int _previousLevel = 0;
+  int _previousGold = 0;
+  int _previousMonstersKilled = 0;
+  int _previousQuestsCompleted = 0;
+
   GameSessionStatus get status => _status;
   GameState? get state => _state;
   String? get error => _error;
   bool get isRunning => _status == GameSessionStatus.running;
   bool get cheatsEnabled => _cheatsEnabled;
 
+  /// 현재 세션 통계
+  SessionStatistics get sessionStats => _sessionStats;
+
+  /// 누적 통계
+  CumulativeStatistics get cumulativeStats => _cumulativeStats;
+
   /// 현재 ProgressLoop 인스턴스 (치트 기능용)
   ProgressLoop? get loop => _loop;
 
@@ -62,6 +81,13 @@ class GameSessionController extends ChangeNotifier {
     _status = GameSessionStatus.running;
     _cheatsEnabled = cheatsEnabled;
 
+    // 통계 초기화
+    if (isNewGame) {
+      _sessionStats = SessionStatistics.empty();
+      await _statisticsStorage.recordGameStart();
+    }
+    _initPreviousValues(state);
+
     _loop = ProgressLoop(
       initialState: state,
       progressService: progressService,
@@ -74,6 +100,7 @@ class GameSessionController extends ChangeNotifier {
     );
 
     _subscription = _loop!.stream.listen((next) {
+      _updateStatistics(next);
       _state = next;
       notifyListeners();
     });
@@ -82,6 +109,76 @@ class GameSessionController extends ChangeNotifier {
     notifyListeners();
   }
 
+  /// 이전 값 초기화 (통계 변화 추적용)
+  void _initPreviousValues(GameState state) {
+    _previousLevel = state.traits.level;
+    _previousGold = state.inventory.gold;
+    _previousMonstersKilled = state.progress.monstersKilled;
+    _previousQuestsCompleted = state.progress.questCount;
+  }
+
+  /// 상태 변화에 따른 통계 업데이트
+  void _updateStatistics(GameState next) {
+    // 플레이 시간 업데이트
+    _sessionStats = _sessionStats.updatePlayTime(next.skillSystem.elapsedMs);
+
+    // 레벨업 감지
+    if (next.traits.level > _previousLevel) {
+      final levelUps = next.traits.level - _previousLevel;
+      for (var i = 0; i < levelUps; i++) {
+        _sessionStats = _sessionStats.recordLevelUp();
+      }
+      _previousLevel = next.traits.level;
+
+      // 최고 레벨 업데이트
+      unawaited(_statisticsStorage.updateHighestLevel(next.traits.level));
+    }
+
+    // 골드 변화 감지
+    if (next.inventory.gold > _previousGold) {
+      final earned = next.inventory.gold - _previousGold;
+      _sessionStats = _sessionStats.recordGoldEarned(earned);
+
+      // 최대 골드 업데이트
+      unawaited(_statisticsStorage.updateHighestGold(next.inventory.gold));
+    } else if (next.inventory.gold < _previousGold) {
+      final spent = _previousGold - next.inventory.gold;
+      _sessionStats = _sessionStats.recordGoldSpent(spent);
+    }
+    _previousGold = next.inventory.gold;
+
+    // 몬스터 처치 감지
+    if (next.progress.monstersKilled > _previousMonstersKilled) {
+      final kills = next.progress.monstersKilled - _previousMonstersKilled;
+      for (var i = 0; i < kills; i++) {
+        _sessionStats = _sessionStats.recordKill();
+      }
+      _previousMonstersKilled = next.progress.monstersKilled;
+    }
+
+    // 퀘스트 완료 감지
+    if (next.progress.questCount > _previousQuestsCompleted) {
+      final quests = next.progress.questCount - _previousQuestsCompleted;
+      for (var i = 0; i < quests; i++) {
+        _sessionStats = _sessionStats.recordQuestComplete();
+      }
+      _previousQuestsCompleted = next.progress.questCount;
+    }
+  }
+
+  /// 누적 통계 로드
+  Future<void> loadCumulativeStats() async {
+    _cumulativeStats = await _statisticsStorage.loadCumulative();
+    notifyListeners();
+  }
+
+  /// 세션 통계를 누적 통계에 병합
+  Future<void> mergeSessionStats() async {
+    await _statisticsStorage.mergeSession(_sessionStats);
+    _cumulativeStats = await _statisticsStorage.loadCumulative();
+    notifyListeners();
+  }
+
   Future<void> loadAndStart({
     String? fileName,
     bool cheatsEnabled = false,
@@ -148,6 +245,7 @@ class GameSessionController extends ChangeNotifier {
 
   /// 플레이어 사망 콜백 (ProgressLoop에서 호출)
   void _onPlayerDied() {
+    _sessionStats = _sessionStats.recordDeath();
     _status = GameSessionStatus.dead;
     notifyListeners();
   }

lib/src/features/game/layouts/mobile_carousel_layout.dart

@@ -39,6 +39,10 @@ class MobileCarouselLayout extends StatefulWidget {
     this.specialAnimation,
     this.currentThemeMode = ThemeMode.system,
     this.onThemeModeChange,
+    this.bgmVolume = 0.7,
+    this.sfxVolume = 0.8,
+    this.onBgmVolumeChange,
+    this.onSfxVolumeChange,
   });
 
   final GameState state;
@@ -56,6 +60,18 @@ class MobileCarouselLayout extends StatefulWidget {
   final ThemeMode currentThemeMode;
   final void Function(ThemeMode mode)? onThemeModeChange;
 
+  /// BGM 볼륨 (0.0 ~ 1.0)
+  final double bgmVolume;
+
+  /// SFX 볼륨 (0.0 ~ 1.0)
+  final double sfxVolume;
+
+  /// BGM 볼륨 변경 콜백
+  final void Function(double volume)? onBgmVolumeChange;
+
+  /// SFX 볼륨 변경 콜백
+  final void Function(double volume)? onSfxVolumeChange;
+
   @override
   State<MobileCarouselLayout> createState() => _MobileCarouselLayoutState();
 }
@@ -200,6 +216,108 @@ class _MobileCarouselLayoutState extends State<MobileCarouselLayout> {
     );
   }
 
+  /// 사운드 상태 텍스트 가져오기
+  String _getSoundStatus() {
+    final bgmPercent = (widget.bgmVolume * 100).round();
+    final sfxPercent = (widget.sfxVolume * 100).round();
+    if (bgmPercent == 0 && sfxPercent == 0) {
+      return l10n.uiSoundOff;
+    }
+    return 'BGM $bgmPercent% / SFX $sfxPercent%';
+  }
+
+  /// 사운드 설정 다이얼로그 표시
+  void _showSoundDialog(BuildContext context) {
+    // StatefulBuilder를 사용하여 다이얼로그 내 상태 관리
+    var bgmVolume = widget.bgmVolume;
+    var sfxVolume = widget.sfxVolume;
+
+    showDialog<void>(
+      context: context,
+      builder: (context) => StatefulBuilder(
+        builder: (context, setDialogState) => AlertDialog(
+          title: Text(l10n.uiSound),
+          content: Column(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              // BGM 볼륨
+              Row(
+                children: [
+                  Icon(
+                    bgmVolume == 0 ? Icons.music_off : Icons.music_note,
+                    color: Theme.of(context).colorScheme.primary,
+                  ),
+                  const SizedBox(width: 8),
+                  Expanded(
+                    child: Column(
+                      crossAxisAlignment: CrossAxisAlignment.start,
+                      children: [
+                        Row(
+                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
+                          children: [
+                            Text(l10n.uiBgmVolume),
+                            Text('${(bgmVolume * 100).round()}%'),
+                          ],
+                        ),
+                        Slider(
+                          value: bgmVolume,
+                          onChanged: (value) {
+                            setDialogState(() => bgmVolume = value);
+                            widget.onBgmVolumeChange?.call(value);
+                          },
+                          divisions: 10,
+                        ),
+                      ],
+                    ),
+                  ),
+                ],
+              ),
+              const SizedBox(height: 8),
+              // SFX 볼륨
+              Row(
+                children: [
+                  Icon(
+                    sfxVolume == 0 ? Icons.volume_off : Icons.volume_up,
+                    color: Theme.of(context).colorScheme.primary,
+                  ),
+                  const SizedBox(width: 8),
+                  Expanded(
+                    child: Column(
+                      crossAxisAlignment: CrossAxisAlignment.start,
+                      children: [
+                        Row(
+                          mainAxisAlignment: MainAxisAlignment.spaceBetween,
+                          children: [
+                            Text(l10n.uiSfxVolume),
+                            Text('${(sfxVolume * 100).round()}%'),
+                          ],
+                        ),
+                        Slider(
+                          value: sfxVolume,
+                          onChanged: (value) {
+                            setDialogState(() => sfxVolume = value);
+                            widget.onSfxVolumeChange?.call(value);
+                          },
+                          divisions: 10,
+                        ),
+                      ],
+                    ),
+                  ),
+                ],
+              ),
+            ],
+          ),
+          actions: [
+            TextButton(
+              onPressed: () => Navigator.pop(context),
+              child: Text(l10n.buttonConfirm),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
   /// 세이브 삭제 확인 다이얼로그 표시
   void _showDeleteConfirmDialog(BuildContext context) {
     showDialog<void>(
@@ -324,6 +442,27 @@ class _MobileCarouselLayoutState extends State<MobileCarouselLayout> {
                 },
               ),
 
+            // 사운드 설정
+            if (widget.onBgmVolumeChange != null ||
+                widget.onSfxVolumeChange != null)
+              ListTile(
+                leading: Icon(
+                  widget.bgmVolume == 0 && widget.sfxVolume == 0
+                      ? Icons.volume_off
+                      : Icons.volume_up,
+                  color: Colors.indigo,
+                ),
+                title: Text(l10n.uiSound),
+                trailing: Text(
+                  _getSoundStatus(),
+                  style: TextStyle(color: Theme.of(context).colorScheme.primary),
+                ),
+                onTap: () {
+                  Navigator.pop(context);
+                  _showSoundDialog(context);
+                },
+              ),
+
             const Divider(),
 
             // 저장
@@ -381,7 +520,7 @@ class _MobileCarouselLayoutState extends State<MobileCarouselLayout> {
         actions: [
           // 옵션 버튼
           IconButton(
-            icon: const Icon(Icons.more_vert),
+            icon: const Icon(Icons.settings),
             onPressed: () => _showOptionsMenu(context),
             tooltip: l10n.menuOptions,
           ),

lib/src/features/game/widgets/ascii_animation_card.dart

@@ -285,6 +285,15 @@ class _AsciiAnimationCardState extends State<AsciiAnimationCard> {
         false,
       ),
 
+      // 디버프 적용 → idle 페이즈 유지
+      CombatEventType.playerDebuff => (
+        BattlePhase.idle,
+        false,
+        false,
+        false,
+        false,
+      ),
+
       // DOT 틱 → attack 페이즈 (지속 피해)
       CombatEventType.dotTick => (
         BattlePhase.attack,

lib/src/features/game/widgets/combat_log.dart

@@ -28,6 +28,7 @@ enum CombatLogType {
   parry, // 무기 쳐내기
   monsterAttack, // 몬스터 공격
   buff, // 버프 활성화
+  debuff, // 디버프 적용
   dotTick, // DOT 틱 데미지
   potion, // 물약 사용
   potionDrop, // 물약 드랍
@@ -166,6 +167,7 @@ class _LogEntryTile extends StatelessWidget {
         Icons.dangerous,
       ),
       CombatLogType.buff => (Colors.lightBlue.shade300, Icons.trending_up),
+      CombatLogType.debuff => (Colors.deepOrange.shade300, Icons.trending_down),
       CombatLogType.dotTick => (Colors.deepPurple.shade300, Icons.whatshot),
       CombatLogType.potion => (Colors.pink.shade300, Icons.local_drink),
       CombatLogType.potionDrop => (Colors.lime.shade300, Icons.card_giftcard),

lib/src/features/game/widgets/death_overlay.dart

@@ -429,6 +429,11 @@ class DeathOverlay extends StatelessWidget {
         Colors.lightBlue.shade300,
         l10n.combatBuffActivated(event.skillName ?? ''),
       ),
+      CombatEventType.playerDebuff => (
+        Icons.trending_down,
+        Colors.deepOrange.shade300,
+        l10n.combatDebuffApplied(event.skillName ?? '', target),
+      ),
       CombatEventType.dotTick => (
         Icons.whatshot,
         Colors.deepOrange.shade300,

lib/src/features/game/widgets/help_dialog.dart

@@ -0,0 +1,553 @@
+import 'package:flutter/material.dart';
+
+/// 도움말 다이얼로그 (Help Dialog)
+///
+/// 게임 메카닉과 UI 설명을 제공
+class HelpDialog extends StatefulWidget {
+  const HelpDialog({super.key});
+
+  /// 다이얼로그 표시
+  static Future<void> show(BuildContext context) {
+    return showDialog(
+      context: context,
+      builder: (_) => const HelpDialog(),
+    );
+  }
+
+  @override
+  State<HelpDialog> createState() => _HelpDialogState();
+}
+
+class _HelpDialogState extends State<HelpDialog>
+    with SingleTickerProviderStateMixin {
+  late TabController _tabController;
+
+  @override
+  void initState() {
+    super.initState();
+    _tabController = TabController(length: 4, vsync: this);
+  }
+
+  @override
+  void dispose() {
+    _tabController.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final isKorean = Localizations.localeOf(context).languageCode == 'ko';
+    final isJapanese = Localizations.localeOf(context).languageCode == 'ja';
+
+    return Dialog(
+      child: Container(
+        constraints: const BoxConstraints(maxWidth: 500, maxHeight: 600),
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            // 헤더
+            Container(
+              padding: const EdgeInsets.all(16),
+              decoration: BoxDecoration(
+                color: theme.colorScheme.primaryContainer,
+                borderRadius: const BorderRadius.vertical(
+                  top: Radius.circular(28),
+                ),
+              ),
+              child: Row(
+                children: [
+                  Icon(
+                    Icons.help_outline,
+                    color: theme.colorScheme.onPrimaryContainer,
+                  ),
+                  const SizedBox(width: 12),
+                  Expanded(
+                    child: Text(
+                      isKorean
+                          ? '게임 도움말'
+                          : isJapanese
+                              ? 'ゲームヘルプ'
+                              : 'Game Help',
+                      style: theme.textTheme.titleLarge?.copyWith(
+                        color: theme.colorScheme.onPrimaryContainer,
+                      ),
+                    ),
+                  ),
+                  IconButton(
+                    icon: const Icon(Icons.close),
+                    onPressed: () => Navigator.of(context).pop(),
+                    color: theme.colorScheme.onPrimaryContainer,
+                  ),
+                ],
+              ),
+            ),
+            // 탭 바
+            TabBar(
+              controller: _tabController,
+              isScrollable: true,
+              tabs: [
+                Tab(
+                  text: isKorean
+                      ? '기본'
+                      : isJapanese
+                          ? '基本'
+                          : 'Basics',
+                ),
+                Tab(
+                  text: isKorean
+                      ? '전투'
+                      : isJapanese
+                          ? '戦闘'
+                          : 'Combat',
+                ),
+                Tab(
+                  text: isKorean
+                      ? '스킬'
+                      : isJapanese
+                          ? 'スキル'
+                          : 'Skills',
+                ),
+                Tab(
+                  text: isKorean
+                      ? 'UI'
+                      : isJapanese
+                          ? 'UI'
+                          : 'UI',
+                ),
+              ],
+            ),
+            // 탭 내용
+            Expanded(
+              child: TabBarView(
+                controller: _tabController,
+                children: [
+                  _BasicsHelpView(
+                    isKorean: isKorean,
+                    isJapanese: isJapanese,
+                  ),
+                  _CombatHelpView(
+                    isKorean: isKorean,
+                    isJapanese: isJapanese,
+                  ),
+                  _SkillsHelpView(
+                    isKorean: isKorean,
+                    isJapanese: isJapanese,
+                  ),
+                  _UIHelpView(
+                    isKorean: isKorean,
+                    isJapanese: isJapanese,
+                  ),
+                ],
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// 기본 도움말 뷰
+class _BasicsHelpView extends StatelessWidget {
+  const _BasicsHelpView({
+    required this.isKorean,
+    required this.isJapanese,
+  });
+
+  final bool isKorean;
+  final bool isJapanese;
+
+  @override
+  Widget build(BuildContext context) {
+    return ListView(
+      padding: const EdgeInsets.all(16),
+      children: [
+        _HelpSection(
+          icon: Icons.info_outline,
+          title: isKorean
+              ? '게임 소개'
+              : isJapanese
+                  ? 'ゲーム紹介'
+                  : 'About the Game',
+          content: isKorean
+              ? 'Askii Never Die는 자동 진행 RPG입니다. 캐릭터가 자동으로 몬스터와 싸우고, '
+                  '퀘스트를 완료하며, 레벨업합니다. 여러분은 장비와 스킬을 관리하면 됩니다.'
+              : isJapanese
+                  ? 'Askii Never Dieは自動進行RPGです。キャラクターが自動でモンスターと戦い、'
+                      'クエストを完了し、レベルアップします。装備とスキルの管理だけで大丈夫です。'
+                  : 'Askii Never Die is an idle RPG. Your character automatically fights monsters, '
+                      'completes quests, and levels up. You manage equipment and skills.',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.trending_up,
+          title: isKorean
+              ? '진행 방식'
+              : isJapanese
+                  ? '進行方式'
+                  : 'Progression',
+          content: isKorean
+              ? '• 몬스터 처치 → 전리품 획득 → 장비 업그레이드\n'
+                  '• 경험치 획득 → 레벨업 → 스탯 상승\n'
+                  '• 퀘스트 완료 → 보상 획득\n'
+                  '• 플롯 진행 → 새로운 Act 해금'
+              : isJapanese
+                  ? '• モンスター討伐 → 戦利品獲得 → 装備アップグレード\n'
+                      '• 経験値獲得 → レベルアップ → ステータス上昇\n'
+                      '• クエスト完了 → 報酬獲得\n'
+                      '• プロット進行 → 新しいAct解放'
+                  : '• Kill monsters → Get loot → Upgrade equipment\n'
+                      '• Gain XP → Level up → Stats increase\n'
+                      '• Complete quests → Get rewards\n'
+                      '• Progress plot → Unlock new Acts',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.save,
+          title: isKorean
+              ? '저장'
+              : isJapanese
+                  ? 'セーブ'
+                  : 'Saving',
+          content: isKorean
+              ? '게임은 자동으로 저장됩니다. 레벨업, 퀘스트 완료, Act 진행 시 자동 저장됩니다. '
+                  '뒤로 가기 시 저장 여부를 선택할 수 있습니다.'
+              : isJapanese
+                  ? 'ゲームは自動保存されます。レベルアップ、クエスト完了、Act進行時に自動保存されます。'
+                      '戻る時に保存するかどうか選択できます。'
+                  : 'The game auto-saves. It saves on level up, quest completion, and Act progression. '
+                      'When exiting, you can choose whether to save.',
+        ),
+      ],
+    );
+  }
+}
+
+/// 전투 도움말 뷰
+class _CombatHelpView extends StatelessWidget {
+  const _CombatHelpView({
+    required this.isKorean,
+    required this.isJapanese,
+  });
+
+  final bool isKorean;
+  final bool isJapanese;
+
+  @override
+  Widget build(BuildContext context) {
+    return ListView(
+      padding: const EdgeInsets.all(16),
+      children: [
+        _HelpSection(
+          icon: Icons.sports_mma,
+          title: isKorean
+              ? '전투 시스템'
+              : isJapanese
+                  ? '戦闘システム'
+                  : 'Combat System',
+          content: isKorean
+              ? '전투는 자동으로 진행됩니다. 플레이어와 몬스터가 번갈아 공격하며, '
+                  '공격 속도(Attack Speed)에 따라 공격 빈도가 결정됩니다.'
+              : isJapanese
+                  ? '戦闘は自動で進行します。プレイヤーとモンスターが交互に攻撃し、'
+                      '攻撃速度(Attack Speed)によって攻撃頻度が決まります。'
+                  : 'Combat is automatic. Player and monster take turns attacking, '
+                      'with attack frequency based on Attack Speed.',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.shield,
+          title: isKorean
+              ? '방어 메카닉'
+              : isJapanese
+                  ? '防御メカニック'
+                  : 'Defense Mechanics',
+          content: isKorean
+              ? '• 회피(Evasion): DEX 기반, 공격을 완전히 피함\n'
+                  '• 방패 방어(Block): 방패 장착 시, 피해 감소\n'
+                  '• 무기 쳐내기(Parry): 무기로 공격 일부 막음\n'
+                  '• 방어력(DEF): 모든 피해에서 차감'
+              : isJapanese
+                  ? '• 回避(Evasion): DEX基準、攻撃を完全に回避\n'
+                      '• 盾防御(Block): 盾装備時、ダメージ軽減\n'
+                      '• 武器受け流し(Parry): 武器で攻撃を一部防ぐ\n'
+                      '• 防御力(DEF): 全ダメージから差し引き'
+                  : '• Evasion: DEX-based, completely avoid attacks\n'
+                      '• Block: With shield, reduce damage\n'
+                      '• Parry: Deflect some damage with weapon\n'
+                      '• DEF: Subtracted from all damage',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.favorite,
+          title: isKorean
+              ? '사망과 부활'
+              : isJapanese
+                  ? '死亡と復活'
+                  : 'Death & Revival',
+          content: isKorean
+              ? 'HP가 0이 되면 사망합니다. 사망 시 장비 하나를 제물로 바쳐 부활할 수 있습니다. '
+                  '부활 후 HP/MP가 완전 회복되고 빈 장비 슬롯에 기본 장비가 지급됩니다.'
+              : isJapanese
+                  ? 'HPが0になると死亡します。死亡時に装備1つを捧げて復活できます。'
+                      '復活後HP/MPが完全回復し、空の装備スロットに基本装備が支給されます。'
+                  : 'You die when HP reaches 0. Sacrifice one equipment piece to revive. '
+                      'After revival, HP/MP fully restore and empty slots get basic equipment.',
+        ),
+      ],
+    );
+  }
+}
+
+/// 스킬 도움말 뷰
+class _SkillsHelpView extends StatelessWidget {
+  const _SkillsHelpView({
+    required this.isKorean,
+    required this.isJapanese,
+  });
+
+  final bool isKorean;
+  final bool isJapanese;
+
+  @override
+  Widget build(BuildContext context) {
+    return ListView(
+      padding: const EdgeInsets.all(16),
+      children: [
+        _HelpSection(
+          icon: Icons.auto_awesome,
+          title: isKorean
+              ? '스킬 종류'
+              : isJapanese
+                  ? 'スキル種類'
+                  : 'Skill Types',
+          content: isKorean
+              ? '• 공격(Attack): 적에게 직접 피해\n'
+                  '• 회복(Heal): HP/MP 회복\n'
+                  '• 버프(Buff): 자신에게 유리한 효과\n'
+                  '• 디버프(Debuff): 적에게 불리한 효과\n'
+                  '• DOT: 시간에 걸쳐 지속 피해'
+              : isJapanese
+                  ? '• 攻撃(Attack): 敵に直接ダメージ\n'
+                      '• 回復(Heal): HP/MP回復\n'
+                      '• バフ(Buff): 自分に有利な効果\n'
+                      '• デバフ(Debuff): 敵に不利な効果\n'
+                      '• DOT: 時間経過でダメージ'
+                  : '• Attack: Deal direct damage\n'
+                      '• Heal: Restore HP/MP\n'
+                      '• Buff: Beneficial effects on self\n'
+                      '• Debuff: Harmful effects on enemies\n'
+                      '• DOT: Damage over time',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.psychology,
+          title: isKorean
+              ? '자동 스킬 선택'
+              : isJapanese
+                  ? '自動スキル選択'
+                  : 'Auto Skill Selection',
+          content: isKorean
+              ? '스킬은 AI가 자동으로 선택합니다:\n'
+                  '1. HP 낮음 → 회복 스킬 우선\n'
+                  '2. HP/MP 충분 → 버프 스킬 사용\n'
+                  '3. 몬스터 HP 높음 → 디버프 적용\n'
+                  '4. 공격 스킬로 마무리'
+              : isJapanese
+                  ? 'スキルはAIが自動選択します：\n'
+                      '1. HP低い → 回復スキル優先\n'
+                      '2. HP/MP十分 → バフスキル使用\n'
+                      '3. モンスターHP高い → デバフ適用\n'
+                      '4. 攻撃スキルで仕上げ'
+                  : 'Skills are auto-selected by AI:\n'
+                      '1. Low HP → Heal skills priority\n'
+                      '2. HP/MP sufficient → Use buff skills\n'
+                      '3. Monster HP high → Apply debuffs\n'
+                      '4. Finish with attack skills',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.upgrade,
+          title: isKorean
+              ? '스킬 랭크'
+              : isJapanese
+                  ? 'スキルランク'
+                  : 'Skill Ranks',
+          content: isKorean
+              ? '스킬은 I ~ IX 랭크가 있습니다. 랭크가 높을수록:\n'
+                  '• 데미지/회복량 증가\n'
+                  '• MP 소모량 증가\n'
+                  '• 쿨타임 증가\n'
+                  '레벨업 시 랜덤하게 스킬을 배웁니다.'
+              : isJapanese
+                  ? 'スキルにはI~IXランクがあります。ランクが高いほど：\n'
+                      '• ダメージ/回復量増加\n'
+                      '• MP消費量増加\n'
+                      '• クールタイム増加\n'
+                      'レベルアップ時にランダムでスキルを習得します。'
+                  : 'Skills have ranks I~IX. Higher rank means:\n'
+                      '• More damage/healing\n'
+                      '• More MP cost\n'
+                      '• Longer cooldown\n'
+                      'Learn random skills on level up.',
+        ),
+      ],
+    );
+  }
+}
+
+/// UI 도움말 뷰
+class _UIHelpView extends StatelessWidget {
+  const _UIHelpView({
+    required this.isKorean,
+    required this.isJapanese,
+  });
+
+  final bool isKorean;
+  final bool isJapanese;
+
+  @override
+  Widget build(BuildContext context) {
+    return ListView(
+      padding: const EdgeInsets.all(16),
+      children: [
+        _HelpSection(
+          icon: Icons.view_column,
+          title: isKorean
+              ? '화면 구성'
+              : isJapanese
+                  ? '画面構成'
+                  : 'Screen Layout',
+          content: isKorean
+              ? '• 상단: 전투 애니메이션, 태스크 진행바\n'
+                  '• 좌측: 캐릭터 정보, HP/MP, 스탯\n'
+                  '• 중앙: 장비, 인벤토리\n'
+                  '• 우측: 플롯/퀘스트 진행, 스펠북'
+              : isJapanese
+                  ? '• 上部: 戦闘アニメーション、タスク進行バー\n'
+                      '• 左側: キャラクター情報、HP/MP、ステータス\n'
+                      '• 中央: 装備、インベントリ\n'
+                      '• 右側: プロット/クエスト進行、スペルブック'
+                  : '• Top: Combat animation, task progress bar\n'
+                      '• Left: Character info, HP/MP, stats\n'
+                      '• Center: Equipment, inventory\n'
+                      '• Right: Plot/quest progress, spellbook',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.speed,
+          title: isKorean
+              ? '속도 조절'
+              : isJapanese
+                  ? '速度調整'
+                  : 'Speed Control',
+          content: isKorean
+              ? '태스크 진행바 옆 속도 버튼으로 게임 속도를 조절할 수 있습니다:\n'
+                  '• 1x: 기본 속도\n'
+                  '• 2x: 2배 속도\n'
+                  '• 5x: 5배 속도\n'
+                  '• 10x: 10배 속도'
+              : isJapanese
+                  ? 'タスク進行バー横の速度ボタンでゲーム速度を調整できます：\n'
+                      '• 1x: 基本速度\n'
+                      '• 2x: 2倍速\n'
+                      '• 5x: 5倍速\n'
+                      '• 10x: 10倍速'
+                  : 'Use the speed button next to task bar to adjust game speed:\n'
+                      '• 1x: Normal speed\n'
+                      '• 2x: 2x speed\n'
+                      '• 5x: 5x speed\n'
+                      '• 10x: 10x speed',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.pause,
+          title: isKorean
+              ? '일시정지'
+              : isJapanese
+                  ? '一時停止'
+                  : 'Pause',
+          content: isKorean
+              ? '일시정지 버튼으로 게임을 멈출 수 있습니다. '
+                  '일시정지 중에도 UI를 확인하고 설정을 변경할 수 있습니다.'
+              : isJapanese
+                  ? '一時停止ボタンでゲームを止められます。'
+                      '一時停止中もUIを確認し設定を変更できます。'
+                  : 'Use the pause button to stop the game. '
+                      'You can still view UI and change settings while paused.',
+        ),
+        const SizedBox(height: 16),
+        _HelpSection(
+          icon: Icons.bar_chart,
+          title: isKorean
+              ? '통계'
+              : isJapanese
+                  ? '統計'
+                  : 'Statistics',
+          content: isKorean
+              ? '통계 버튼에서 현재 세션과 누적 게임 통계를 확인할 수 있습니다. '
+                  '처치한 몬스터, 획득 골드, 플레이 시간 등을 추적합니다.'
+              : isJapanese
+                  ? '統計ボタンで現在のセッションと累積ゲーム統計を確認できます。'
+                      '倒したモンスター、獲得ゴールド、プレイ時間などを追跡します。'
+                  : 'View current session and cumulative stats in the statistics button. '
+                      'Track monsters killed, gold earned, play time, etc.',
+        ),
+      ],
+    );
+  }
+}
+
+/// 도움말 섹션 위젯
+class _HelpSection extends StatelessWidget {
+  const _HelpSection({
+    required this.icon,
+    required this.title,
+    required this.content,
+  });
+
+  final IconData icon;
+  final String title;
+  final String content;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        // 섹션 헤더
+        Row(
+          children: [
+            Icon(icon, size: 20, color: theme.colorScheme.primary),
+            const SizedBox(width: 8),
+            Text(
+              title,
+              style: theme.textTheme.titleMedium?.copyWith(
+                fontWeight: FontWeight.bold,
+                color: theme.colorScheme.primary,
+              ),
+            ),
+          ],
+        ),
+        const SizedBox(height: 8),
+        // 내용
+        Container(
+          padding: const EdgeInsets.all(12),
+          decoration: BoxDecoration(
+            color: theme.colorScheme.surfaceContainerHighest.withValues(alpha: 0.5),
+            borderRadius: BorderRadius.circular(8),
+          ),
+          child: Text(
+            content,
+            style: theme.textTheme.bodyMedium?.copyWith(
+              height: 1.5,
+            ),
+          ),
+        ),
+      ],
+    );
+  }
+}

lib/src/features/game/widgets/statistics_dialog.dart

@@ -0,0 +1,705 @@
+import 'package:flutter/material.dart';
+
+import 'package:askiineverdie/src/core/model/game_statistics.dart';
+
+/// 게임 통계 다이얼로그 (Statistics Dialog)
+///
+/// 세션 통계와 누적 통계를 탭으로 표시
+class StatisticsDialog extends StatefulWidget {
+  const StatisticsDialog({
+    super.key,
+    required this.session,
+    required this.cumulative,
+  });
+
+  final SessionStatistics session;
+  final CumulativeStatistics cumulative;
+
+  /// 다이얼로그 표시
+  static Future<void> show(
+    BuildContext context, {
+    required SessionStatistics session,
+    required CumulativeStatistics cumulative,
+  }) {
+    return showDialog(
+      context: context,
+      builder: (_) => StatisticsDialog(
+        session: session,
+        cumulative: cumulative,
+      ),
+    );
+  }
+
+  @override
+  State<StatisticsDialog> createState() => _StatisticsDialogState();
+}
+
+class _StatisticsDialogState extends State<StatisticsDialog>
+    with SingleTickerProviderStateMixin {
+  late TabController _tabController;
+
+  @override
+  void initState() {
+    super.initState();
+    _tabController = TabController(length: 2, vsync: this);
+  }
+
+  @override
+  void dispose() {
+    _tabController.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+    final isKorean = Localizations.localeOf(context).languageCode == 'ko';
+    final isJapanese = Localizations.localeOf(context).languageCode == 'ja';
+
+    return Dialog(
+      child: Container(
+        constraints: const BoxConstraints(maxWidth: 400, maxHeight: 500),
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            // 헤더
+            Container(
+              padding: const EdgeInsets.all(16),
+              decoration: BoxDecoration(
+                color: theme.colorScheme.primaryContainer,
+                borderRadius: const BorderRadius.vertical(
+                  top: Radius.circular(28),
+                ),
+              ),
+              child: Row(
+                children: [
+                  Icon(
+                    Icons.bar_chart,
+                    color: theme.colorScheme.onPrimaryContainer,
+                  ),
+                  const SizedBox(width: 12),
+                  Expanded(
+                    child: Text(
+                      isKorean
+                          ? '게임 통계'
+                          : isJapanese
+                              ? 'ゲーム統計'
+                              : 'Game Statistics',
+                      style: theme.textTheme.titleLarge?.copyWith(
+                        color: theme.colorScheme.onPrimaryContainer,
+                      ),
+                    ),
+                  ),
+                  IconButton(
+                    icon: const Icon(Icons.close),
+                    onPressed: () => Navigator.of(context).pop(),
+                    color: theme.colorScheme.onPrimaryContainer,
+                  ),
+                ],
+              ),
+            ),
+            // 탭 바
+            TabBar(
+              controller: _tabController,
+              tabs: [
+                Tab(
+                  text: isKorean
+                      ? '현재 세션'
+                      : isJapanese
+                          ? '現在のセッション'
+                          : 'Session',
+                ),
+                Tab(
+                  text: isKorean
+                      ? '누적 통계'
+                      : isJapanese
+                          ? '累積統計'
+                          : 'Cumulative',
+                ),
+              ],
+            ),
+            // 탭 내용
+            Expanded(
+              child: TabBarView(
+                controller: _tabController,
+                children: [
+                  _SessionStatisticsView(stats: widget.session),
+                  _CumulativeStatisticsView(stats: widget.cumulative),
+                ],
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// 세션 통계 뷰
+class _SessionStatisticsView extends StatelessWidget {
+  const _SessionStatisticsView({required this.stats});
+
+  final SessionStatistics stats;
+
+  @override
+  Widget build(BuildContext context) {
+    final isKorean = Localizations.localeOf(context).languageCode == 'ko';
+    final isJapanese = Localizations.localeOf(context).languageCode == 'ja';
+
+    return ListView(
+      padding: const EdgeInsets.all(16),
+      children: [
+        _StatSection(
+          title: isKorean
+              ? '전투'
+              : isJapanese
+                  ? '戦闘'
+                  : 'Combat',
+          icon: Icons.sports_mma,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '플레이 시간'
+                  : isJapanese
+                      ? 'プレイ時間'
+                      : 'Play Time',
+              value: stats.formattedPlayTime,
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '처치한 몬스터'
+                  : isJapanese
+                      ? '倒したモンスター'
+                      : 'Monsters Killed',
+              value: _formatNumber(stats.monstersKilled),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '보스 처치'
+                  : isJapanese
+                      ? 'ボス討伐'
+                      : 'Bosses Defeated',
+              value: _formatNumber(stats.bossesDefeated),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '사망 횟수'
+                  : isJapanese
+                      ? '死亡回数'
+                      : 'Deaths',
+              value: _formatNumber(stats.deathCount),
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '데미지'
+              : isJapanese
+                  ? 'ダメージ'
+                  : 'Damage',
+          icon: Icons.flash_on,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '입힌 데미지'
+                  : isJapanese
+                      ? '与えたダメージ'
+                      : 'Damage Dealt',
+              value: _formatNumber(stats.totalDamageDealt),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '받은 데미지'
+                  : isJapanese
+                      ? '受けたダメージ'
+                      : 'Damage Taken',
+              value: _formatNumber(stats.totalDamageTaken),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '평균 DPS'
+                  : isJapanese
+                      ? '平均DPS'
+                      : 'Average DPS',
+              value: stats.averageDps.toStringAsFixed(1),
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '스킬'
+              : isJapanese
+                  ? 'スキル'
+                  : 'Skills',
+          icon: Icons.auto_awesome,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '스킬 사용'
+                  : isJapanese
+                      ? 'スキル使用'
+                      : 'Skills Used',
+              value: _formatNumber(stats.skillsUsed),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '크리티컬 히트'
+                  : isJapanese
+                      ? 'クリティカルヒット'
+                      : 'Critical Hits',
+              value: _formatNumber(stats.criticalHits),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '최대 연속 크리티컬'
+                  : isJapanese
+                      ? '最大連続クリティカル'
+                      : 'Max Critical Streak',
+              value: _formatNumber(stats.maxCriticalStreak),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '크리티컬 비율'
+                  : isJapanese
+                      ? 'クリティカル率'
+                      : 'Critical Rate',
+              value: '${(stats.criticalRate * 100).toStringAsFixed(1)}%',
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '경제'
+              : isJapanese
+                  ? '経済'
+                  : 'Economy',
+          icon: Icons.monetization_on,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '획득 골드'
+                  : isJapanese
+                      ? '獲得ゴールド'
+                      : 'Gold Earned',
+              value: _formatNumber(stats.goldEarned),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '소비 골드'
+                  : isJapanese
+                      ? '消費ゴールド'
+                      : 'Gold Spent',
+              value: _formatNumber(stats.goldSpent),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '판매 아이템'
+                  : isJapanese
+                      ? '売却アイテム'
+                      : 'Items Sold',
+              value: _formatNumber(stats.itemsSold),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '물약 사용'
+                  : isJapanese
+                      ? 'ポーション使用'
+                      : 'Potions Used',
+              value: _formatNumber(stats.potionsUsed),
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '진행'
+              : isJapanese
+                  ? '進行'
+                  : 'Progress',
+          icon: Icons.trending_up,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '레벨업'
+                  : isJapanese
+                      ? 'レベルアップ'
+                      : 'Level Ups',
+              value: _formatNumber(stats.levelUps),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '완료한 퀘스트'
+                  : isJapanese
+                      ? '完了したクエスト'
+                      : 'Quests Completed',
+              value: _formatNumber(stats.questsCompleted),
+            ),
+          ],
+        ),
+      ],
+    );
+  }
+}
+
+/// 누적 통계 뷰
+class _CumulativeStatisticsView extends StatelessWidget {
+  const _CumulativeStatisticsView({required this.stats});
+
+  final CumulativeStatistics stats;
+
+  @override
+  Widget build(BuildContext context) {
+    final isKorean = Localizations.localeOf(context).languageCode == 'ko';
+    final isJapanese = Localizations.localeOf(context).languageCode == 'ja';
+
+    return ListView(
+      padding: const EdgeInsets.all(16),
+      children: [
+        _StatSection(
+          title: isKorean
+              ? '기록'
+              : isJapanese
+                  ? '記録'
+                  : 'Records',
+          icon: Icons.emoji_events,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '최고 레벨'
+                  : isJapanese
+                      ? '最高レベル'
+                      : 'Highest Level',
+              value: _formatNumber(stats.highestLevel),
+              highlight: true,
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '최대 보유 골드'
+                  : isJapanese
+                      ? '最大所持ゴールド'
+                      : 'Highest Gold Held',
+              value: _formatNumber(stats.highestGoldHeld),
+              highlight: true,
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '최고 연속 크리티컬'
+                  : isJapanese
+                      ? '最高連続クリティカル'
+                      : 'Best Critical Streak',
+              value: _formatNumber(stats.bestCriticalStreak),
+              highlight: true,
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '총 플레이'
+              : isJapanese
+                  ? '総プレイ'
+                  : 'Total Play',
+          icon: Icons.access_time,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '총 플레이 시간'
+                  : isJapanese
+                      ? '総プレイ時間'
+                      : 'Total Play Time',
+              value: stats.formattedTotalPlayTime,
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '시작한 게임'
+                  : isJapanese
+                      ? '開始したゲーム'
+                      : 'Games Started',
+              value: _formatNumber(stats.gamesStarted),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '클리어한 게임'
+                  : isJapanese
+                      ? 'クリアしたゲーム'
+                      : 'Games Completed',
+              value: _formatNumber(stats.gamesCompleted),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '클리어율'
+                  : isJapanese
+                      ? 'クリア率'
+                      : 'Completion Rate',
+              value: '${(stats.completionRate * 100).toStringAsFixed(1)}%',
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '총 전투'
+              : isJapanese
+                  ? '総戦闘'
+                  : 'Total Combat',
+          icon: Icons.sports_mma,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '처치한 몬스터'
+                  : isJapanese
+                      ? '倒したモンスター'
+                      : 'Monsters Killed',
+              value: _formatNumber(stats.totalMonstersKilled),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '보스 처치'
+                  : isJapanese
+                      ? 'ボス討伐'
+                      : 'Bosses Defeated',
+              value: _formatNumber(stats.totalBossesDefeated),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '총 사망'
+                  : isJapanese
+                      ? '総死亡'
+                      : 'Total Deaths',
+              value: _formatNumber(stats.totalDeaths),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '총 레벨업'
+                  : isJapanese
+                      ? '総レベルアップ'
+                      : 'Total Level Ups',
+              value: _formatNumber(stats.totalLevelUps),
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '총 데미지'
+              : isJapanese
+                  ? '総ダメージ'
+                  : 'Total Damage',
+          icon: Icons.flash_on,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '입힌 데미지'
+                  : isJapanese
+                      ? '与えたダメージ'
+                      : 'Damage Dealt',
+              value: _formatNumber(stats.totalDamageDealt),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '받은 데미지'
+                  : isJapanese
+                      ? '受けたダメージ'
+                      : 'Damage Taken',
+              value: _formatNumber(stats.totalDamageTaken),
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '총 스킬'
+              : isJapanese
+                  ? '総スキル'
+                  : 'Total Skills',
+          icon: Icons.auto_awesome,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '스킬 사용'
+                  : isJapanese
+                      ? 'スキル使用'
+                      : 'Skills Used',
+              value: _formatNumber(stats.totalSkillsUsed),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '크리티컬 히트'
+                  : isJapanese
+                      ? 'クリティカルヒット'
+                      : 'Critical Hits',
+              value: _formatNumber(stats.totalCriticalHits),
+            ),
+          ],
+        ),
+        const SizedBox(height: 16),
+        _StatSection(
+          title: isKorean
+              ? '총 경제'
+              : isJapanese
+                  ? '総経済'
+                  : 'Total Economy',
+          icon: Icons.monetization_on,
+          items: [
+            _StatItem(
+              label: isKorean
+                  ? '획득 골드'
+                  : isJapanese
+                      ? '獲得ゴールド'
+                      : 'Gold Earned',
+              value: _formatNumber(stats.totalGoldEarned),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '소비 골드'
+                  : isJapanese
+                      ? '消費ゴールド'
+                      : 'Gold Spent',
+              value: _formatNumber(stats.totalGoldSpent),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '판매 아이템'
+                  : isJapanese
+                      ? '売却アイテム'
+                      : 'Items Sold',
+              value: _formatNumber(stats.totalItemsSold),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '물약 사용'
+                  : isJapanese
+                      ? 'ポーション使用'
+                      : 'Potions Used',
+              value: _formatNumber(stats.totalPotionsUsed),
+            ),
+            _StatItem(
+              label: isKorean
+                  ? '완료 퀘스트'
+                  : isJapanese
+                      ? '完了クエスト'
+                      : 'Quests Completed',
+              value: _formatNumber(stats.totalQuestsCompleted),
+            ),
+          ],
+        ),
+      ],
+    );
+  }
+}
+
+/// 통계 섹션 위젯
+class _StatSection extends StatelessWidget {
+  const _StatSection({
+    required this.title,
+    required this.icon,
+    required this.items,
+  });
+
+  final String title;
+  final IconData icon;
+  final List<_StatItem> items;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        // 섹션 헤더
+        Row(
+          children: [
+            Icon(icon, size: 18, color: theme.colorScheme.primary),
+            const SizedBox(width: 8),
+            Text(
+              title,
+              style: theme.textTheme.titleSmall?.copyWith(
+                fontWeight: FontWeight.bold,
+                color: theme.colorScheme.primary,
+              ),
+            ),
+          ],
+        ),
+        const Divider(height: 8),
+        // 통계 항목들
+        ...items,
+      ],
+    );
+  }
+}
+
+/// 개별 통계 항목 위젯
+class _StatItem extends StatelessWidget {
+  const _StatItem({
+    required this.label,
+    required this.value,
+    this.highlight = false,
+  });
+
+  final String label;
+  final String value;
+  final bool highlight;
+
+  @override
+  Widget build(BuildContext context) {
+    final theme = Theme.of(context);
+
+    return Padding(
+      padding: const EdgeInsets.symmetric(vertical: 4),
+      child: Row(
+        mainAxisAlignment: MainAxisAlignment.spaceBetween,
+        children: [
+          Text(
+            label,
+            style: theme.textTheme.bodyMedium?.copyWith(
+              color: theme.colorScheme.onSurfaceVariant,
+            ),
+          ),
+          Container(
+            padding: highlight
+                ? const EdgeInsets.symmetric(horizontal: 8, vertical: 2)
+                : null,
+            decoration: highlight
+                ? BoxDecoration(
+                    color: theme.colorScheme.primaryContainer,
+                    borderRadius: BorderRadius.circular(4),
+                  )
+                : null,
+            child: Text(
+              value,
+              style: theme.textTheme.bodyMedium?.copyWith(
+                fontWeight: FontWeight.bold,
+                fontFamily: 'monospace',
+                color: highlight
+                    ? theme.colorScheme.onPrimaryContainer
+                    : theme.colorScheme.onSurface,
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+/// 숫자 포맷팅 (천 단위 콤마)
+String _formatNumber(int value) {
+  if (value < 1000) return value.toString();
+
+  final result = StringBuffer();
+  final str = value.toString();
+  final length = str.length;
+
+  for (var i = 0; i < length; i++) {
+    if (i > 0 && (length - i) % 3 == 0) {
+      result.write(',');
+    }
+    result.write(str[i]);
+  }
+
+  return result.toString();
+}