Sacrifice (chess)

In chess, a sacrifice is a move giving up a piece with the objective of gaining tactical or positional compensation in other forms. A sacrifice could also be a deliberate exchange of a chess piece of higher value for an opponent's piece of lower value.

Any chess piece except the king may be sacrificed. Because players usually try to hold on to their own pieces, offering a sacrifice can come as an unpleasant surprise to one's opponent, putting him off balance and causing much precious time to be wasted trying to calculate whether the sacrifice is sound or not and whether to accept it. Sacrificing one's queen (the most valuable piece), or a string of pieces, adds to the surprise, and such games can be awarded brilliancy prizes.

Rudolf Spielmann proposed a division between sham and real sacrifices:

In compensation for a real sacrifice, the player receives dynamic advantages which he must capitalize on, or risk losing the game due to the material deficit. Because of the risk involved, real sacrifices are also called speculative sacrifices.

Attack on the king. A player might sacrifice a pawn or piece to get open lines around the vicinity of the opponent's king, to get a kingside space advantage, to destroy or damage the opposing king's pawn cover, or to keep the opposing king in the center. Unless the opponent manages to fend off the attack, he is likely to lose. The Greek gift sacrifice is a canonical example.

Development. It is common to give up a pawn in the opening to speed up one's development. Gambits typically fall into this category. Developing sacrifices are frequently returned at some point by the opponent before the development edge can turn into a more substantial threat such as a kingside attack.

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