Figure[Black to move]

Here is another “if only” position. Look for alignments in White’s camp and you see his king and queen adjacent on the same dark-squared diagonal. Black has his dark-squared bishop available, and could inflict a skewer on h6 if only White’s bishop on g5 weren't in the way. How can Black overcome it? He can't capture the bishop, and it protects nothing else that he can take. On the other hand it is loose, and indeed White has nothing he can use to defend it promptly. So threaten it. Black plays Qf5, and the bishop is forced to move to a square where it has some protection: Bh4. Now the skewering square is loose and the line is clear for Black to play Bh6+. White’s only way to save the position is to interpose his knight on f4 (always check for interpositions!), but then Black takes the knight with his e5 pawn, winning a piece.