Tactics & checkmates
Discovered check
A discovered check occurs when one piece moves out of another friendly piece’s line, uncovering an attack on the enemy king. The moving piece can create a second threat against a queen or rook. If both pieces give check, it is a double check.
A practical example
White has a rook on e1 and bishop on e2; Black has a king on e8. With the rest of the e-file clear, Bb5+ reveals the rook’s check. The rook, rather than the bishop, gives check.
A common mistake
Considering only the moving piece’s new threat. Its move must be legal, and a single discovered check can sometimes be answered by a capture or interposition.
Try this in your next review
Find friendly pieces in front of bishops, rooks and queens. Check which moves uncover check and whether the moving piece can create an additional threat.
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