121. a piece already in the way, by the chariot

Helpmates in xiangqi

4 moves

Black moves first and both sides cooperate: Black, Red, Black, Red, and Red's second move mates. Black has 40 legal first moves and exactly one of them works. 15 pieces, Black 36 to Red 11 in material, mate by the chariot. Themes: a piece already in the way, the general walks in,…