Zukertort Opening Pirc Invitation Fork Puzzle (Rated 1349): Spot Mate in 3 — Queen Sacrifice
This middlegame puzzle shows how a queen sacrifice can force a mating net when the enemy king is stuck in the center. The key idea is not material, but king safety: once the first check lands, the defender’s king is driven onto vulnerable squares where a knight and queen coordinate to finish the attack. The bishop on the long diagonal helps create the tactical geometry, while the exposed king has too few safe squares to escape.