- rules like standard chess, but without king rule (king may be moved into check)
- there is a ball initially on e4 (or d4, d5 or e5).
- a sliding piece (rook, bishop, queen) may not leap over the ball
- if a piece moves onto the ball, the moving player kicks the ball in an orthogonal or diagonal direction any distance, but only over empty squares. The ball is kicked onto an empty square or to the square with the opponent’s king, thereby capturing the king
- the goal is to capture the opponent’s king, either by the ball or by a piece