Chess tactics, motif by motif

Double check

Two pieces give check at once. The king has to move: nothing can block or capture both.

Discovered attack

A piece moves out of the way and reveals an attack from the piece behind it, so two threats land at once.

Skewer

A line attack on a valuable piece that, when it moves, exposes a piece behind it.

Pin

A piece cannot move (or should not) because a more valuable piece sits behind it on the line.

Fork

One piece attacks two targets at once, and only one can be saved.

X-ray

A line piece attacks or defends THROUGH an enemy piece, along the line behind it.

Interference

A piece is thrown between two enemy pieces to cut the line that connected them.

Zwischenzug

An in-between move: instead of the expected recapture, a threat that must be answered first.

Clearance

A piece vacates a square or a line, often with tempo, so another piece can use it.

Removing the defender

Capture the piece that guards the target, then take the target.

Attraction

A sacrifice that pulls a piece, usually the king, onto a square where a second blow lands.

Deflection

Force a piece away from the duty it was performing, and the thing it guarded falls.

Trapped piece

A piece has no safe square left. Attack it and it is lost.

Hanging piece

A piece that nobody defends. Just take it, or attack it so it cannot be saved.

Exposed king

A king without pawn cover: checks and threats come with tempo.

Quiet move

No check, no capture, and yet the strongest move: a threat the opponent cannot meet.

Smothered mate

A knight delivers mate to a king boxed in by its own pieces.

Anastasia's mate

A knight and a rook (or queen) trap the king against the side of the board.

Arabian mate

A knight and a rook team up in the corner: the rook mates, the knight covers the escape.

Boden's mate

Two bishops on criss-crossing diagonals mate a king blocked by its own pieces.

Dovetail mate

A queen mates diagonally adjacent to the king, whose two escape squares are taken by its own pieces.

Double bishop mate

Two bishops on adjacent diagonals mate a king on the edge.

Hook mate

A rook, a knight and a pawn work together: the rook mates, the knight guards it, the pawn guards the knight.

Kill box mate

A rook mates next to the king while a queen, two squares away, boxes it into three squares.

Corner mate

A knight mates a king in the corner, with a rook (or queen) cutting off the edge.

Triangle mate

A queen and a rook form a triangle with the king, which has nowhere to go.

Swallow's tail mate

A queen mates face to face with the king, whose two diagonal escapes are blocked by its own pieces.

Epaulette mate

A queen mates a king flanked by two of its own pieces, like epaulettes.

Morphy's mate

A bishop mates a king in the corner while a rook takes away the edge.

Opera mate

A rook mates on the back rank, protected by a bishop on the long diagonal.

Pillsbury's mate

A rook mates on the g-file, with a bishop on the long diagonal covering the corner.

Blind swine mate

Two rooks on the seventh rank mate a king in the corner.

Vukovic mate

A rook mates on the edge, protected by a knight, with the knight also covering the escape.

Balestra mate

A queen and a bishop: the queen mates at a knight's distance, the bishop cuts the diagonal escape.

Back rank mate

A rook or queen mates a king trapped behind its own unmoved pawns.

En passant

The pawn capture people forget exists, and the tactic hidden inside it.

Promotion

A pawn reaches the last rank, or the threat of it decides the game.

Advanced pawn

A pawn on the sixth or seventh rank is a tactical weapon: it costs a piece to stop.

Zugzwang

Every move worsens the position. Hand the move over and let them wreck themselves.

Defensive move

The only move that holds: find the defence before the attack lands.