Chess Tactics: Forks, Pins, Skewers and Mating Patterns

How to spot a tactic

Tactics do not appear at random. They appear when something in the position is loose: a piece with no defender, a king without an escape square, or two valuable pieces standing on the same line. Strong players notice these details first and look for the move that exploits them second.

A reliable routine is to look at forcing moves before anything else. Checks come first, because the reply is limited. Captures come next, and then moves that make a direct threat. Run through the same list for your opponent before you let go of your piece, since the most common blunder is a move that walks into a tactic.

Which pieces, on either side, have no defender?
Which pieces are lined up on one file, rank or diagonal?
Can either king be checked, and where could it go?
Is any piece doing two defensive jobs at once?

The fork: two targets, one move

A fork is a single move that attacks two or more pieces. The opponent can only move one of them, so the other is lost. Any piece can give a fork. Knights are the best known for it, because a knight’s attack cannot be blocked and its odd move is easy to overlook, and a knight fork that includes a check is especially strong.

The humble pawn is just as dangerous. A pawn attacks two squares at once, and because it is the least valuable unit on the board, whatever it forks is worth more than it is. Queens fork too, usually by giving check while attacking a loose piece on the other side of the board.

A pawn fork. The pawn steps from d4 to d5 and attacks the knight and the bishop at once. The pawn on e4 protects it, so Black must lose a piece.

The pin: a piece that cannot move

A pin happens on a line. A bishop, rook or queen attacks an enemy piece, and a more valuable piece stands behind it. If the piece behind is the king, the pin is absolute: the pinned piece is not allowed to move at all. If the piece behind is a queen or rook, the pinned piece may move, but only at a heavy price.

A pinned piece is a poor defender, because it cannot leave its line to recapture. The usual way to profit from a pin is to attack the pinned piece again, ideally with a pawn. To get out of a pin, move the valuable piece off the line, put something in between, or chase the pinning piece away.

The bishop on b5 pins the knight to the king, so the knight cannot legally move. White attacks it again by pushing the pawn to d5 and will win it.

The skewer: a pin turned around

In a skewer the more valuable piece is in front. It is attacked and has to move, and the piece behind it is captured. The most common skewer is a check along a rank, file or diagonal: the king steps aside and whatever stood behind it falls.

Skewers turn up most often in endgames, when kings and queens wander onto open lines. Before you put your king and queen on the same rank, file or diagonal, check whether an enemy rook, bishop or queen can reach that line.

The rook checks from a5. The king has to leave the fifth rank, and the rook then captures the queen on g5.

Discovered attacks and double check

A discovered attack is made by moving one piece out of the way of another. The piece that moves can make a threat of its own, so the opponent faces two threats from a single move. When the uncovered piece attacks the king it is a discovered check, and the piece that moved can go almost anywhere, even to a square where it could normally be captured, because the check must be answered first.

If the moving piece gives check as well, the result is a double check. Two attackers cannot both be blocked or captured in one move, so the king has to move. Many of the prettiest checkmates in chess history end with a double check.

Removing the defender

Often the move you want does not work because one enemy piece is guarding the crucial square. The question then becomes how to get rid of that guard. The simplest way is to capture it, even at a small cost: this is removing the defender.

If the guard cannot be captured, it can sometimes be dragged away. A deflection forces it to leave its post, typically by attacking it or by offering a sacrifice it has to accept. A decoy does the opposite and lures a piece onto a bad square. An overloaded piece has two things to protect; make it deal with one and the other falls.

A zwischenzug, or in-between move, belongs to the same family. Instead of making the obvious recapture, you first play a check or a bigger threat, and recapture afterwards on better terms. Whenever a capture seems to force your reply, take a moment to ask whether something stronger is available first.

Mating patterns: the back rank

Checkmates follow patterns too. The one that catches the most players is the back-rank mate. A castled king sits behind three unmoved pawns, the rooks have left the back rank, and an enemy rook or queen lands there with check. The pawns that were sheltering the king now block every escape square.

The cure is one quiet pawn move. Pushing the h-pawn or g-pawn a single square gives the king an escape hatch, which players call luft. Make that move when you have a spare tempo and nothing more urgent to do, and keep a rook on the back rank until you have.

A rarer but memorable pattern is the smothered mate, in which a lone knight checkmates a king that is boxed in on all sides by its own pieces.

The rook goes to e8 and it is checkmate: Black’s own pawns hold the king in. White’s king is safe from the same trick because the pawn on h3 has made room on h2.

Getting better at tactics

Tactical skill is mostly pattern recognition, and patterns are learned by repetition. Solving a few puzzles a day does more good than an occasional long session. Take your time on each one and work out the whole line before you play the first move; guessing teaches very little.

Your own games are the best puzzle book. After each one, find the moment where material was won or lost and name the pattern involved. On LarkSpark, the middle bot levels take any material you leave undefended, which makes them honest sparring partners for exactly this. Unfamiliar words are explained in the glossary, and once you are winning material regularly, the endgames page shows how to turn an extra piece or pawn into a win.