OnChain Battleship - Complete MVP

A fully functional Battleship game implementation using Merkle proofs for verification without zero-knowledge proofs.

📥 How to Download Everything

Method 1: Download Individual Files

Click on each file name below to download:

• Smart Contract: ImprovedOnChainBattleship.sol
• Package Config: package.json
• Hardhat Config: hardhat.config.js
• Deployment Script: deploy.js
• Environment Template: .env.example

🚀 Smart Contract Setup

1. Create Project Directory

mkdir onchain-battleship
cd onchain-battleship

2. Initialize Node.js Project

npm init -y

3. Install Dependencies

npm install --save-dev hardhat @nomicfoundation/hardhat-toolbox
npm install @openzeppelin/contracts

4. Create Directory Structure

mkdir contracts
mkdir scripts
mkdir test

5. Move Files to Correct Locations

• Move ImprovedOnChainBattleship.sol to contracts/
• Move deploy.js to scripts/
• Keep hardhat.config.js and package.json in root directory
• Copy .env.example to .env and fill in your values

🔧 Environment Setup

1. Create .env File

cp .env.example .env

2. Fill in Your Values

PRIVATE_KEY=your_private_key_here
SEPOLIA_RPC_URL=https://rpc.sepolia.org
ETHERSCAN_API_KEY=your_etherscan_api_key_here

⚠️ IMPORTANT: Never share your private key! Use a testnet wallet.

🎯 Deploy Contract

1. Compile Contract

npx hardhat compile

2. Deploy to Sepolia Testnet

npx hardhat run scripts/deploy.js --network sepolia

3. Verify Contract (Optional)

npx hardhat verify CONTRACT_ADDRESS --network sepolia

📋 Project Structure

onchain-battleship/
├── contracts/
│   └── ImprovedOnChainBattleship.sol
├── scripts/
│   └── deploy.js
├── test/
├── hardhat.config.js
├── package.json
├── .env.example
└── README.md

🎮 Frontend Usage

The frontend is completely standalone and works without any blockchain connection:

1. Ship Placement: Drag and drop 5 ships onto your 10x10 grid
2. Battle Phase: Click enemy grid squares to attack
3. Visual Effects: See explosions for hits, splashes for misses
4. Victory: Game ends when all ships are destroyed

🔒 Security Features

Smart Contract Security

• ReentrancyGuard: Prevents reentrancy attacks
• Pausable: Emergency stop functionality
• Ownable: Owner controls for emergency situations
• Input Validation: Coordinate and state validation
• Timeout System: Prevents griefing attacks

Game Integrity

• Merkle Proof Verification: All moves verified cryptographically
• Anti-Cheat System: Economic penalties for invalid proofs
• Timeout Mechanisms: 24-hour move timeout, 7-day reveal timeout
• Slashing Logic: Cheaters forfeit their stakes

💰 Game Economics

• Stake: 0.1 ETH per game (perfect for testnet)
• Winner Takes All: Winner receives both stakes (0.2 ETH total)
• Slashing: Cheaters lose their stake to honest players
• Timeouts: Non-responsive players forfeit their stakes

🧪 Testing

Run Tests

npx hardhat test

Local Development

npx hardhat node

🌐 Network Support

• Sepolia Testnet: Recommended for testing
• Goerli Testnet: Alternative testnet
• Mainnet: Production deployment

📖 Game Rules

1. Standard Battleship: 5 ships (Carrier:5, Battleship:4, Cruiser:3, Submarine:3, Destroyer:2)
2. Turn-Based: Players alternate making guesses
3. Merkle Proofs: All hits/misses verified cryptographically
4. Win Condition: First to sink all opponent ships wins
5. Anti-Cheat: Invalid proofs result in automatic loss

🆘 Troubleshooting

Common Issues

1. "Invalid private key": Make sure your private key is 64 characters (without 0x prefix)
2. "Insufficient funds": Ensure your wallet has testnet ETH
3. "Contract not found": Check if contract address is correct
4. "Network error": Verify RPC URL is working

Get Testnet ETH

• Sepolia: https://sepoliafaucet.com/
• Goerli: https://goerlifaucet.com/

📚 Additional Resources

• Hardhat Documentation
• OpenZeppelin Contracts
• Ethereum Testnets

🎯 Next Steps

1. Test Locally: Deploy to local hardhat network
2. Testnet Deployment: Deploy to Sepolia testnet
3. Frontend Integration: Connect frontend to deployed contract
4. Security Audit: Professional security review
5. Mainnet Launch: Production deployment

🤝 Support

For questions or issues:

1. Check the troubleshooting section
2. Review Hardhat documentation
3. Test on local network first
4. Verify all environment variables are set correctly

Status: Ready for deployment and testing! 🚢⚓