Checkmate With Bishop And Knight Puzzle (Rated 1392): Spot a Pin — Mate in 1
A pin can turn an apparently powerful defender into a prisoner. In this middlegame position, a rook attacks along an open file and fixes a bishop in place because moving it would expose the king. That absolute pin restricts the defender’s legal options and creates a mating net around the exposed king. The key tactical idea is to notice how the pinned piece, weakened escape squares, and a nearby knight combine to produce an immediate checkmate.