Discovered Attack
Moving one piece reveals a hidden attack from another piece behind it.
Published 2026-02-01 | Last verified 2026-02-12
Professor Archer says: The discovered attack is what I call a "two-for-one" in chess. You make one move, but you create two threats. It is like a magician pulling back a curtain to reveal a surprise behind it. The piece that moves is the curtain, and the piece that was hidden is the surprise. When I teach this concept, I always see the same spark of understanding in my students' eyes — the moment they realize that every piece on a line can potentially be part of a discovered attack, their tactical vision expands dramatically.
The Mechanics of a Discovered Attack
A discovered attack is one of the most powerful tactical devices in chess because it creates two threats in a single move. Here is how it works: two of your pieces stand on the same line (rank, file, or diagonal). The piece in front moves away, and the piece behind it is suddenly attacking an enemy piece or the enemy king.
What makes this so devastating is that the piece that moves is free to go anywhere it wants, including squares where it creates its own independent threat. So you end up with two attacks at once: the revealed attack from the piece behind, and whatever the moved piece is now threatening.
For example, imagine a White bishop on c1 aiming at Black's queen on h6, but a White knight on e3 is blocking the diagonal. If the knight moves to f5 (attacking Black's rook on d6, say), the bishop's attack on the queen is simultaneously revealed. Black must deal with both threats but can only make one move. Something has to give.
The "discovering" piece (the one that moves) can be any piece at all, including a pawn. The "discovered" piece (the one revealed) must be a line piece — a bishop, rook, or queen — because only line pieces attack along continuous lines that can be unblocked.
Discovered attacks are especially potent when the discovered piece delivers check, because check must be answered immediately, giving the discovering piece a free hand to wreak havoc elsewhere on the board.
Setting Up a Discovered Attack
Discovered attacks do not usually appear spontaneously. They require the right alignment of pieces, and skilled players create these alignments through careful maneuvering.
The first step is recognizing the potential. Any time two of your pieces share the same line with an enemy target, there is a potential discovered attack. The piece in front just needs a good reason to move. Your job as a chess player is to find that reason — ideally, a square where the moving piece creates its own threat.
Consider the position shown. In many Italian Game positions, White's pieces naturally align on key diagonals and files. The bishop on c4 aims toward f7, one of the weakest squares in Black's camp. If a White knight or pawn stands between the bishop and f7, moving that piece could unleash the bishop with devastating effect.
One common technique for setting up discovered attacks is the "battery." A battery is when two line pieces are aligned on the same line — for example, a queen behind a bishop on the same diagonal, or a queen behind a rook on the same file. Batteries are discovered attacks waiting to happen. The front piece just needs to move with a purpose.
Practice looking for alignments in your games. After each move, scan the board for lines where your pieces share a path with an enemy target. Over time, this becomes automatic.
In the Italian Game, pieces naturally align on diagonals and files, creating potential discovered attack setups.
Types of Discovered Attacks
Discovered attacks come in several varieties, each with its own level of force.
The standard discovered attack creates two threats: one from the moved piece and one from the revealed piece. The opponent must choose which threat to address. If both threats target different pieces, the attacker usually wins material.
A discovered check is a discovered attack where the revealed piece gives check to the enemy king. This is far more forcing because check must be answered immediately, giving the moved piece a completely free turn. The moved piece can capture the queen, promote a pawn, or do anything else without the opponent being able to respond to it.
A double check is the most powerful form: both the moved piece and the revealed piece give check simultaneously. The only way to escape a double check is to move the king — you cannot block or capture two attackers at once. Double checks often lead directly to checkmate.
There is also the discovered attack with a capture, where the moving piece takes an enemy piece as it clears the line. This combines material gain with the revealed threat, creating a particularly profitable situation.
Understanding these gradations helps you prioritize your search during a game. Always check for discovered checks first (they are the most forcing), then standard discovered attacks. The most forcing move is usually the best move to calculate first.
Defending Against Discovered Attacks
Defending against discovered attacks requires vigilance and awareness of piece alignments. Here are the key defensive principles.
First, always be aware of lines. After every move, check whether any of your pieces has moved onto the same rank, file, or diagonal as the enemy king or another valuable piece. If your piece stands between an enemy line piece and your king, you are vulnerable to a discovered attack.
Second, avoid placing your king on open lines where enemy pieces can operate. An open diagonal pointed at your king is a discovered attack waiting to happen. This is one reason why fianchettoed bishops (placed on g2 or b2) are so valued — they help control key diagonals and reduce the risk of discovered attacks.
Third, pay attention to enemy batteries. If your opponent aligns two pieces on the same line, they are likely preparing a discovered attack. Consider disrupting their plan by exchanging one of the aligned pieces, blocking the line, or moving your vulnerable piece off the targeted line.
Fourth, when you see a discovered attack coming, look for defensive resources. Can you block the discovered line? Can you capture the piece that is about to discover the attack? Can you create a counter-threat that forces your opponent to abandon their plan?
The best defense against discovered attacks is prophylactic play — preventing them before they arise by keeping your pieces off dangerous lines and maintaining awareness of the alignments on the board.
Frequently Asked Questions
What is a discovered attack in chess?
A discovered attack occurs when one piece moves out of the way, revealing an attack from a line piece (bishop, rook, or queen) behind it. This creates two simultaneous threats: one from the piece that moved and one from the piece that was uncovered.
How do you use a discovered attack in a game?
Align two of your pieces on the same line as an enemy target. When the front piece moves to create its own threat (ideally a capture or an attack on a valuable piece), the revealed piece attacks the enemy target simultaneously, giving the opponent two problems to solve with one move.
Professor Archer says: Study discovered attacks patiently. The best ones in real games are rarely obvious. They require you to notice that two of your pieces share a line with an enemy target, and that one of them can move away productively. Once you train your eye to see these line relationships, a whole new dimension of chess opens up for you.
Quick Quiz
In a discovered attack, what is the role of the piece that moves?
- It must deliver check to the enemy king - The moved piece does not need to deliver check. It can create any threat or simply move to a better square. When it does give check, it becomes a discovered check, a specific subtype.
- It clears the line and ideally creates its own separate threat (Correct) - Correct. The moving piece unblocks the line for the piece behind it and should ideally create its own threat, resulting in two simultaneous attacks.
- It must capture an enemy piece as it moves - The moving piece does not have to capture anything. It just needs to clear the line. Capturing is a bonus but not a requirement.
- It must be a bishop or rook to create the discovery - Any piece can be the discovering piece — even a pawn. It is the piece behind (the one being uncovered) that must be a line piece like a bishop, rook, or queen.