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Bodens mate

Boden's Mate is a checkmate involving two bishops and one king (usually on the edge) with two pieces of the same color. The idea is that one bishop attacks one diagonal, and the other bishop attacks a perpendicular diagonal of a different color. Where the two diagonals meet, there is a 2x2 square region of control, and the king is caught in one of those tiles. The last two adjacent Flight squares on the king's side are blocked by two of his very own pieces.

Boden's mate typically occurs on the ends of the c-file, where the king has castled queenside.

Boden's mate was coined for Samuel Boden, a 19th century chess master. He played the mate pattern in a match, Schulder–Boden, London 1853.