A. Chess Tactics

1. Direct attacks

1.1 Fork: One piece attacks two or more enemy pieces simultaneously.

1.2 Pin: A piece is unable to move because doing so would expose a more valuable piece (or the King) behind it (only bishops/rooks/queens can do this)

1.3 Skewer: A piece attacks a valuable enemy piece, forcing it to move and exposing a less valuable piece behind it; pin has more valuable piece behind less valuable one; skewer is the reverse; only bishops/rooks/queens can do this

1.4 Discovered Attack: Moving a piece to unblock a line of attack for a friendly piece standing behind it. Also includes Discovered Check and Double Check.

1.5 Hanging Pieces: Leaving a piece unprotected and exposed to capture.

2. Breaking defences

2.1 Overloading: Targeting a defensive piece that is trying to protect too many squares or pieces at once.

2.2 Undermining: Capturing or driving away a defending piece to leave an enemy target vulnerable (also called "Removing the Defender").

2.3 Deflection: Forcing a key defender to move away from its job

2.4 Decoy: Forcing a piece to a bad or “poison square”

2.5 Pawn break through: Breaking through a pawn shield to attack the king.

3. Combos

3.1 Sacrifice: Deliberately giving up material to gain a tactical or positional advantage (e.g., to clear a square or open a line); Includes Queen Sacrifice, Exchange Sacrifice, and Clearance Sacrifice

3.2 Overloading: Targeting a defensive piece that is trying to protect too many squares or pieces at once.

3.3 Intermezzo: Playing a surprising "in-between" move that creates a new threat before responding to the opponent's previous move.

3.4 X-Ray attack: Attacking through a piece to pressure or target what lies behind it; only bishops/rooks/queens can do this

3.5 Battery: Lining up two pieces in a row (bishop, rook, or queen) to form an attack across a line or diagonal

4. Rare but powerful

4.1 Piece trap: Forcing a piece into inescapable capture

4.2 Interference: Placing a piece to block an enemy line of defense or communication

4.3 Windmill: A repeated series of discovered checks that lets you capture material between checks; only bishops/rooks/queens can do this

4.4 Desperado: Using a piece that will be lost to try to capture the best opponent piece along the way

5. Endgame wins

5.1 Simplification: when winning, trade pieces with opponent to avoid complicated games that could lead to mistakes

5.2 Zugzwang: (move compulsion) – Any move worsens your position because you are forced to move

5.3 Smothered Mate: Checkmate delivered when the king is trapped by its own pieces, usually via a knight.

5.4 Underpromotion: Promoting a pawn to a piece other than a queen for tactical reasons

6. Endgame draws

6.1 Forced stalemate: Deliberately engineering a position with no legal moves but not in check.

6.2 Perpetual check: Checking repeatedly so the opponent cannot escape, forcing a draw.

6.3 Fortress: create a protected wall so opponent can’t penetrate without a sacrifice