Learn How to Use X-Ray Attack: Mate in 3
This puzzle shows how a hidden line of pressure can turn an apparently active rook into a decisive tactical weapon. The key idea is an x-ray attack: one piece attacks through another piece on the same file or rank, creating a forcing sequence that wins time and restricts the king. In a sharp chess endgame, that kind of collinear pressure often matters more than material count, especially when the enemy king is boxed in and the back rank is vulnerable.