Turn your strategy into code, then test it in battle

It starts with six lines

You don't play the game here. You write the code that plays it. Below is an entire rock-paper-scissors strategy. Paste it into the editor on that screen and it runs.

var next = 2;              // rock on the first turn

function onGameStart() {}
function onRoundStart() {}

function onTurnStart() {
	return next;           // 1 scissors · 2 rock · 3 paper
}

function onTurnEnd(result) {
	next = result.opponentchoice % 3 + 1;
}

function onRoundEnd() {}
function onGameEnd() {}

1. Read the rules and the callback contract in the sample code.
2. Implement your strategy yourself, or hand it to a coding agent. Each game screen has a spec-copy button you can feed straight to an agent.
3. Battle the AI, an online opponent or the Code Arena, then read the log and fix it.

A GAME is several ROUNDs, and a ROUND is several TURNs. Each TURN's choice decides the ROUND and the GAME. Anything you send to printLog() appears in the log area at the bottom of the screen.