- 1. Bxc1+ Kxa2 2. axb5#
Other defences
- 1. Bxc1+ b2 2. axb5#
Position
- White
- king on e5, queen on a5, bishop on d2, knight on h8, pawns on a2, a4, c4, f2 and g4
- Black
- king on a3, rook on c1, bishops on b1 and c5, knights on a1 and a6, pawns on b3, b4, b5, c6, d3 and d5