Shadow Strike

Shadow Strike is a privacy-first on-chain battle game that uses Fully Homomorphic Encryption (FHE) on Zama’s FHEVM. Players register a character name and receive randomly-generated encrypted stats (HP, Attack, Defense). Battles are computed entirely on encrypted data, so player stats never leave ciphertext — only battle outcomes (as encrypted handles) are produced and selectively authorized for players to decrypt.

Table of contents

• What is Shadow Strike?
• High-level flow (how a battle works)
• Project layout & where to look next
• License

What is Shadow Strike?

Shadow Strike is a turn-based one-round battle game built on FHEVM where:

• Players register with a name; the contract generates random encrypted stats for fairness.
• When two players fight, the contract calculates damage and remaining HP using encrypted arithmetic.
• The contract records an encrypted result for each player (win/lose/draw) and a unique battleId.
• Each result handle is explicitly authorized so the rightful player(s) can decrypt it off-chain (e.g., in tests or the UI).
• The contract emits an event including battleId so clients can reliably map the transaction to the stored encrypted result.

The goal: let players compete on chain while keeping sensitive game state private.

High-level flow (how a battle works)

1. Registration

• Players register with a name.
• The contract generates random stats (HP, Attack, Defense) in encrypted form.
• Stats are stored on-chain, keeping them private.

2. Challenge & Battle

• One player challenges another.
• The contract computes damage and determines the winner using encrypted calculations.
• The battle result is stored as an encrypted handle and a unique battleId is assigned.
• Only the involved players are allowed to decrypt their results.

3. Client-side decryption

• After the battle, the frontend listens for the battle event and fetches the result handle.
• Each player can decrypt their own result locally to see if they won, lost, or drew.

Key idea: All calculations and stats stay private; only each player sees their own outcome.

Project layout & where to look next

• contracts/Readme.md - (Contracts README) Contains detailed instructions for:
  • Building, testing, and deploying smart contracts
  • FHEVM / Hardhat config notes
• app/Readme.md - (Frontend README) Contains:
  • How to run the frontend app
  • How to connect to Sepolia testnet

You can jump directly to those docs:

• Contracts: contracts/Readme.md
• Frontend app: app/Readme.md

License

MIT — see LICENSE in this repository.