46. model mate, by the cannon

Helpmates in xiangqi

4 moves

Black moves first and both sides cooperate: Black, Red, Black, Red, and Red's second move mates. Black has 30 legal first moves and exactly one of them works. 16 pieces, Black 37.5 to Red 6.5 in material, mate by the cannon. Themes: pure mate, model mate, the cannon fires over a…