Grid3

What it proves

A whole game can live in one cell. Grid3 keeps the board, both players, the turn and the stake in a game cell, and each move is a transaction that replaces it. The type script does not run the game; it only accepts or rejects each proposed state change, which is how CKB scripts work.

How it uses CKB

The game cell moves through four states: waiting, active, finished and cancelled. The script checks that a move is signed by the player whose turn it is, changes exactly one empty square and flips the turn. When a game ends it checks the winning line against the board and the payout: 80% of the pool to the winner and 20% to a fee address, or the stakes split evenly on a draw. The player who opened a game can cancel it and take the stake back until someone joins. The full design is in SPEC.md in the repository.

Before mainnet

It runs on testnet only, and no audit of the script is published. Real stakes would need one.