Learn How to Spot Mate in 1: Pillsbury's Mate
This puzzle is a classic mating pattern built around a rook invasion on the g-file, where the enemy king has too few escape squares and its own pieces help seal the net. In middlegame positions like this, material can matter less than king safety: a single active rook can turn a winning advantage into immediate checkmate. The key idea is to recognize when a checking piece lands on a square that attacks the king directly while also controlling the flight squares.