Figure[Black to move]

Decoys on the Diagonal: Bishop Check Sacrifices.

The decoys, or “flush” checks, considered in the previous set of positions were administered by rooks. But bishops can do it, too.

In the position to the left, some elements familiar from our last batch of studies are visible: White’s king protects its queen, and the queen is under attack by its opposite number. This makes you want to check the king to pull it away and leave White’s queen loose. You have no rook available for the purpose—but consider all of your options and you find that you do have a bishop. Black plays Bc2+, and the consequence of the check is the same as if it were administered by a rook: the king must capture or else allow the queen to be skewered. White plays KxB, at least picking up the bishop before leaving his queen loose and permitting Black to play QxQ+ next move.