114. pure mate, 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 39 legal first moves and exactly one of them works. 20 pieces, Black 53 to Red 15 in material, mate by the chariot. Themes: pure mate, a piece already in the way, the genera…