Perpetual check and perpetual chase

Perpetual check with one piece or several pieces is not allowed. The side that keeps giving check loses the game. Perpetual chase of one unprotected piece is also banned, except a chase by a general or a soldier. When one side checks forever and the other chases forever, the checking side must stop or lose.

Without this rule, a losing player could check forever and force a draw by repetition. The rules treat an endless check as a violation, not a normal draw. The rule pushes players to make real progress instead of repeating the same moves.

This site uses a simple, automatic rule instead of a full arbiter review. If the same position repeats a third time, and one side gave check on every occurrence, that side loses. Any other threefold repetition ends the game as a plain draw. The engine does not detect a perpetual chase on its own. Players should treat a clear, repeated chase the same way, by agreement.

Rule sets differ on how many repeats count as perpetual. Wikipedia's Xiangqi article names one common club standard, which allows six checks in a row with one piece. Two pieces raise that count to twelve, and three pieces raise it to eighteen. This site uses its own simpler repetition rule instead.