Reversi Stone & Shadow | HTML5 Game With AI and PVP

Game Modes

• VS AI – Three difficulty tiers (Easy / Medium / Hard)
• Two Players – Local play on one device
• Online PvP – Real-time multiplayer via Firebase Realtime Database. Quick Match auto-pairs players. Create or join private rooms using a 6-character code. In-game chat included.

AI Difficulty

• Easy – Shallow depth + randomized moves
• Medium – Balanced depth + full heuristic scoring
• Hard – Maximum depth + corner-prioritized opening + tight alpha-beta cutoffs

Themes (8 + Custom Builder)

• Obsidian (free) / Crimson (free) / Arctic / Amber / Violet / Neon / Sakura / Marble
• Custom Theme Builder – Live preview, 6 color pickers, preset themes (Forest, Ocean, Rose Gold, Slate, Sand, Jade)
• Themes above Crimson are unlocked with in-game coins earned through gameplay

Coin & Economy System

• Earn coins by winning games vs AI or Online PvP – stored locally, no account needed
• Spend coins to unlock themes or buy in-game power-ups from the store
• Power-Ups: Hint Pack, Undo Pack, XP Boost, Board Flip, Champion Title
• Hint Button – Uses a Hint Pack to flash the best move on the board. Works in all game modes.
• Watch a voluntary reward ad to earn +25 coins instantly

Online PvP Features

• Quick Match – Atomic Firebase transaction matchmaking. Works even when both players click at the exact same moment.
• Create Room – Generate a 6-character code and share with a friend
• Join Room – Enter a friend’s code to connect directly
• In-Game Chat – Real-time messaging during the match
• Turn Timer – 10-second countdown per turn. Auto-passes if time runs out.
• Disconnect Detection – Opponent going offline is detected and handled gracefully
• Display Names – Random or custom names shown in the HUD during the match

Controls

• Click / Tap – Place disc
• Hint Button – Flash best move (requires Hint Pack)
• Lobby – Return to main screen
• Resign / Exit – Leave online match (notifies opponent)

Overlay System

• Game Over / Pause / Assign Opponent / Quit Confirm / Resign Confirm
• Zero native popups – custom HTML overlays throughout

Advertisement System

• Reward ad, match start, then pop-up ads show, and while quitting it
• User watches 15 seconds and earns +25 coins
• Placeholder sized to Google AdSense 300×250 Medium Rectangle standard – ready for integration

Tech Stack

• HTML5 Canvas 2D
• CSS Custom Properties (theme tokens)
• Web Audio API (optional)
• requestAnimationFrame (60fps, offscreen board cache)
• ES2015+ JavaScript (IIFE-scoped, no global leaks)
• Firebase Realtime Database (loaded on demand, not on page load)
• Google Fonts – Cinzel, Crimson Pro – loaded via Google Fonts CDN at runtime; requires an internet connection for optimal typography

Requirements

• Chrome / Firefox / Safari / Edge / Opera (Latest)
• Internet connection required for Online PvP and Google Fonts
• No build step – open index.html directly or deploy to any static host