3balance

3balance is an onchain mini app where players pick a crypto character, sign a match entry transaction on Base, and fight in a fast 1v1 arena.

The core idea is simple: every new match starts with an onchain action. Gameplay is offchain and instant, while entry analytics stay transparent onchain.

What It Does

• Sends an onchain enterMatch(characterId) transaction before battle start.
• Uses Base Account + OnchainKit MiniKit inside Base App.
• Supports sponsored gas flow through Coinbase Paymaster when available.
• Shows player profile from MiniKit context (displayName, username, avatar).
• Runs battle gameplay with character selection, lives, coin control, AI behavior, and win/lose states.
• Supports result sharing to feed via composeCast, with browser fallback (navigator.share or copy link).

Game Flow

1. Open app.
2. Pick fighter.
3. Sign entry transaction on Base.
4. Fight opponent in arena.
5. Share result.

Tech Stack

• React 19 + Vite 7
• wagmi + viem
• @coinbase/onchainkit
• Base Mainnet
• Solidity (entry contract)

Smart Contract

Contract source: contracts/BattleArenaEntry.sol

Main entry function:

function enterMatch(string calldata characterId) external

The contract stores:

• Total entries
• Unique players
• Entries per player
• Entries per character (by hash)
• Last entry timestamp per player

Environment Variables

Create .env.local and set:

VITE_PUBLIC_ONCHAINKIT_API_KEY=your_onchainkit_api_key
VITE_BATTLE_ENTRY_CONTRACT=0xYourBattleArenaEntryContract
VITE_APP_URL=https://3balances.vercel.app

Notes:

• VITE_BATTLE_ENTRY_CONTRACT has a default fallback in src/App.jsx if env is missing.
• Paymaster RPC URL is currently configured directly in src/App.jsx.

Local Development

pnpm install
pnpm dev

Build and checks:

pnpm lint
pnpm build
pnpm preview

Mini App Metadata

Metadata files:

• public/.well-known/farcaster.json
• index.html (fc:miniapp tag)

Screenshots and cover assets:

• public/cover-1200x630.png
• public/screenshots/screenshot-1.png
• public/screenshots/screenshot-2.png
• public/screenshots/screenshot-3.png

Assets

Character images:

• public/battle/characters/

Coin icons:

• public/battle/coins/

Project Structure

• src/App.jsx - app shell, wallet/profile, entry tx, share logic, navigation
• src/BattleArena.jsx - game screen and mechanics
• src/main.jsx - OnchainKit provider bootstrap
• contracts/BattleArenaEntry.sol - onchain match entry contract

Current Status

• Main gameplay and onchain entry flow are live.
• Browser fallback is enabled if MiniKit is unavailable.
• UI is optimized for mobile mini app usage.

License

MIT