Learn How to Spot Mate in 2: Back Rank Mate
This puzzle is a classic mating net built around king safety and rook activity. Even in a middlegame, a seemingly active defense can collapse when the enemy king has limited flight squares and the back rank is vulnerable. The key idea is to force the king into a narrower box, then use a rook to deliver a checking move that cannot be met by interposition or escape. Patterns like this often appear after a tactical invasion on the seventh rank.