Lesson
White to move. Main line: 1. Qxc6+ bxc6 2. Ba6#
Qxc6 is the line-opening sacrifice: only the b7-pawn can recapture (the knight on d7 blocks the king’s escape and cannot take on c6), and with b7 gone, Ba6 arrives with mate — b8 and c7 are already held by the dark-squared bishop.
The mating picture is two bishops slicing across the king on crossing diagonals: one holds b8 and c7, the other delivers on the a6–c8 line, while the king’s own pawns and rook seal the rest.
Boden’s mate is THE pattern to know against a queenside-castled king. The trigger to look for: a pawn on c6 (or c3 for Black) that can be forced to abandon the b7 square.