4. A chariot, and nothing spare

Helpmates in xiangqi

4 moves

Black’s chariot swings from a10 to e9 and plugs its own palace. The red chariot takes the horse on b10 and mates along the back rank, with the advisor on f10 sealing the last square. Black moves first and both sides cooperate: Black, Red, Black, Red, and Red's second move mates.…