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a b c d e f g h
8 a8 b8 c8 B d8 e8 f8 g8 h8 8
7 a7 b7 c7 d7 e7 f7 g7 h7 7
6 a6 b6 c6 d6 e6 f6 n g6 h6 6
5 a5 b5 c5 d5 p e5 k+ f5 g5 h5 5
4 a4 b4 c4 d4 e4 f4 g4 h4 4
3 a3 b3 c3 d3 e3 K f3 g3 B~ h3 3
2 a2 b2 c2 d2 e2 f2 ~~ g2 h2 2
1 a1 b1 c1 d1 e1 f1 g1 h1 1
a b c d e f g h
Double bishop mate example.
Double bishop

The Double bishop mate is a checkmate with two bishops on adjacent parallel diagonals (in contrast to Boden's mate with bishops on perpendicular diagonals); one of which delivers the mate. The remaining flight squares are controlled by the attacking side or more commonly, occupied by pieces on the defensive.