Discovered Attacks
Move one piece, and a completely different piece delivers the blow.
Moving piece + uncovered line piece
White to move — reveal the attack.
Hint
Something is blocking one of your own pieces. Move it somewhere useful.
Tap a piece, then tap where it should go.
A double check — both the moving piece and the revealed piece giving check at once — can only be answered by moving the king.
Learn double attacksA discovered attack happens when you move a piece that was blocking one of your own long-range pieces (a bishop, rook, or queen), revealing an attack that piece was already lined up to make.
The moving piece is free to do something useful of its own — capture, attack a third piece, or simply improve its square — while the piece behind it does the real damage. When the revealed attack is check, it's specifically called a discovered check.
Moving piece + uncovered line piece
Two pieces are always involved: the one that moves (which can go almost anywhere useful, since it isn't the one delivering the main threat) and the long-range piece behind it, whose attack was blocked until that moment.
Discovered check
When the newly revealed line hits the enemy king, it's a discovered check — and often a dangerous one, because the moving piece can deliver its own threat (a capture, a fork, even checkmate) in total safety, since the opponent must deal with the check first.
Why discovered attacks are easy to miss
Unlike a direct attack, nothing about the moving piece's own destination looks dangerous — the danger comes from a piece that wasn't 'doing anything' the move before. That's exactly what makes them hard to spot for the side being attacked.
Frequently asked questions
What's the difference between a discovered attack and a discovered check?
A discovered check is a discovered attack where the revealed line hits the enemy king specifically. Every discovered check is a discovered attack; not every discovered attack is a check.
Why are discovered checks so strong?
The opponent must respond to the check immediately, which means the piece that moved is free to capture something or create a second threat with no risk of an immediate reply.
Can the moving piece also give check itself?
Yes — if both the moving piece and the revealed piece attack the king at once, that's a double check, which can only be answered by moving the king (blocking or capturing can't stop two attackers at once).
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