Amateur games are decided by a short tactical shot more often than by strategy: a piece is left undefended, two pieces end up on the same line, or a check opens a second threat. Most of these shots are built on four tactics: the fork, the pin, the skewer and the discovered attack. Each has a diagram below, with the signs to look for on the board.
The Fork: One Piece, Two Targets
A fork is one piece attacking two or more of the opponent’s pieces at once. Your opponent has one move and can save only one of them, so you take the other.
The knight forks more often than any other piece. It jumps over whatever stands in its way, so its attack cannot be blocked, and a queen or rook it attacks cannot capture it. Any piece can fork, though: a pawn can attack two pieces, a queen can hit a king and a rook, and in the endgame even a king can attack two undefended pieces.
A fork with check is the most dangerous kind. The check has to be answered, and that leaves no move to save the other piece.
How to spot it: look for a square from which one of your pieces attacks two enemy pieces at once. Try the knight first and see whether it has a check that also hits the queen or a rook.
The Pin: A Piece That Can’t Leave the Line
A pin involves three pieces on one line. Your bishop, rook or queen attacks an enemy piece, and a more valuable enemy piece stands behind it. If the front piece moves off the line, the one behind comes under attack, so the front piece is called pinned.
There are two kinds. In an absolute pin the pinned piece shields its king. It cannot leave the line, because the rules forbid exposing your own king to check. In a relative pin the piece behind is any other piece, most often the queen. Moving away is legal, but it costs material.
A pinned piece is a poor defender, and it cannot run from an attack. So you attack it again, with a pawn or a minor piece. Once it is attacked more times than it is defended, you win it.
How to spot it: look for an enemy piece standing on a line between your bishop, rook or queen and a more valuable enemy piece. Then count whether you can attack it more times than your opponent can defend it.
The Skewer: The Pin Turned Around
A skewer is carried out by the same pieces as a pin: the rook, the bishop and the queen. The difference is that the more valuable enemy piece stands in front. It is under attack and has to move, and you take the piece that stood behind it on the same line.
A skewer usually comes with check: the king has to move, and the piece behind it is left exposed.
How to spot it: when your rook, bishop or queen can give check or attack a valuable piece, look at what stands further along the same line. If a piece is there, you take it as soon as the front one moves.
The Discovered Attack: Two Threats From One Move
A discovered attack needs two of your pieces on one line. The front piece moves away and uncovers the attack of the piece behind it, and it makes a threat of its own as it goes. Your opponent faces two threats and has one move.
In the diagram the check comes from the knight, the piece that left the diagonal, and the bishop takes the queen. It can be the other way round: the piece behind gives the check once its line is opened. That is a discovered check, the strongest form of discovered attack. The front piece can attack almost anything, because while your opponent answers the check there is no time to defend the second target.
How to spot it: look for a bishop, rook or queen of yours that is aimed at an enemy piece but blocked by one of your own pieces. Then see whether the blocking piece can move away with check or with a threat.
How to Find These Tactics in a Game
The four often appear together. A knight fork works because the piece that guarded the square is pinned. A discovered attack opens a line, and the piece behind uses it for a skewer. The same routine before every move finds any of them:
- Look at every check, capture and threat, yours and your opponent’s.
- Find the undefended pieces, the pieces that share a file, rank or diagonal, and the pieces a knight attacks from a single square.
- If there are two targets, see which of the four tactics fits them.
The habit forms faster when you look for these tactics in your own games, both the ones you missed and the ones your opponent missed. Paste a username, a game link or a PGN into the field below. Stockfish labels every move and shows the best move in each position, and the evaluation before and after a move tells you what a missed fork or a hung piece cost.
Go through a few of your recent games this way and see which of the four you miss most often. Then solve puzzles on that one: each of the four has its own theme in the puzzles section.
Related
- Common Chess Mistakes: the mistakes these tactics punish, and how to stop making them.
- How to Analyze Your Chess Games: how to look for missed tactics in a game, step by step.
- Understanding Chess Accuracy: what the accuracy percentage shows.
- Free Chess Analysis: Stockfish analyzes your games for free, with no daily limit.