An almost identical pattern seen from White’s side. You notice that the bishop masks the queen on d1; the queen otherwise would be able to take Black’s queen, which is loose. So White clears the bishop from the d-file and creates a distraction at the same time with Bg6+. Black has to address the check; after he takes White’s bishop, Black’s queen is lost. The more common checking move in this sort of position has the bishop taking the pawn on h2 or h7 and thus giving check to the castled king as we saw in the previous cases; but as this position shows, you want to look for every possible check you may be able to give with the unmasking piece.