Colle System Puzzle (Rated 871): Fork — Win Material
This Colle System middlegame features a classic double attack: a checking bishop move simultaneously challenges the exposed queen and intensifies pressure around the centralized king. Black’s king is safely sheltered, while White’s king remains uncastled and vulnerable. The key tactical idea exploits the value of forcing moves. Even though White begins with extra material and central space, Black can turn king safety and piece activity into a decisive material gain.