If the scores of a move are less than S for M consecutive moves, then resign. M and S are subject to mutation.

• Victory by checkmate: Loser replaced by copy of winner.
• Victory by resignation: Loser replaced by offspring of winner and loser.
• Draw: Loser determined by coin flip, replaced by offspring of winner and loser.

Expectation: If the gene is too eager to resign, that gene will fade away as it always loses. If it never resigns, then it goes away at the first loss or with a 50% chance on every non-checkmate result.