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Pawn — moves forward one square (two on its first move), captures diagonally.
Knight — moves in an L-shape (2+1 squares), can jump over pieces.
Bishop — moves any number of squares diagonally.
Rook — moves any number of squares horizontally or vertically.
Queen — combines the rook and bishop; any direction, any distance.
King — moves one square in any direction.

Your king is in check when it's under attack — you must move out of check immediately. If there's no legal way to escape, it's checkmate and the game ends.

Castling — king and rook move together for safety, if neither has moved and the squares between them are empty and not under attack.
En Passant — a special pawn capture that can happen right after an opponent's pawn moves two squares past yours.
Promotion — a pawn reaching the far end of the board becomes a queen (or another piece of your choice).

Outsmart the AI engine with tactful plays. If the AI gets you, hit New Game and try again!