Ruy Lopez Hanging Piece Puzzle (Rated 811): Back Rank Mate — Mate in 1

This puzzle is a classic back rank mate pattern in a middlegame setting. The key idea is that the enemy king’s escape squares are restricted by its own pawns and pieces, so a rook invasion on the back rank can end the game immediately. Even when material is balanced or slightly unfavorable, a direct mating net can outweigh everything else. Look for open files, pinned defenders, and a king with no luft.