Queens Indian Defense Petrosian Variation Puzzle (Rated 1218): Exploit Discovered Attack — Classical Chess Puzzle with Theory & Hints

This middlegame puzzle is a classic example of a discovered attack, where one piece moves with tempo and opens a stronger line for another attacker behind it. The key idea is that the opponent’s most active piece can become a tactical target when a hidden file, diagonal, or queen line is revealed. In positions like this, a forcing capture can win material by exposing a loose knight or overloaded defender, turning a balanced board into a decisive advantage.