Discovered Attacks
How to spot it: look for your own rook, bishop, or queen aimed at an enemy target but blocked by one of your own pieces. Ask: where can that blocker go to also create a threat? Two attacks for the price of one.
How to recognise it in a game
Find your long-range pieces whose lines are blocked by one of your own pieces. Then ask where the blocker can move with tempo. The strongest discoveries make the moving piece and the revealed piece create separate threats.
The common calculation mistake
Moving the blocker is not automatically strong. Check whether the revealed line actually reaches a valuable target and whether the moving piece has a safe, useful destination.
How to defend against it
When an enemy bishop, rook or queen is lined up behind one of its own active pieces, treat that front piece as a potential trigger. Moving the target off the line or trading the rear attacker can remove the discovery before it happens.
Now spot it yourself
A real position: find the move. This is exactly what the drills in the app do, banded from beginner to expert.
How this lesson is made: this public explanation comes from the authored Strong Squares curriculum. Automated checks protect its chess data, source fields and learning flow. Independent chess-editor approval remains part of the private-preview release process. Read the teaching method.