A rowdy audience drops boulders onto the board.
How to play
You play White against a Black bot while a simulated audience watches. Every few moves a spectator drops a boulder onto an empty square. Boulders block movement and attack lines for both sides and cannot be captured; each one crumbles after a few moves. Spectators sometimes drop several at once or clear the board. Normal checkmate rules decide the game. Pawns auto-promote to queens.