Zugzwang is a position in which it is disadvantageous to move, as every move leads to a worse, and often lost position. Most of the time it happens in late endgames, specially pawn endings, the most obvious example being a KPK endgame, where opposition can be regarded as a special case of zugzwang.

Zugzwang and Null Move

Zugzwang positions are known cause the Null Move Pruning go wrong. For that reason most programs do not use null move in the late endings. As far as middlegame positions are concerned, programmers either assume that they happen too rarely to bother with them, or use some sort of verification pruning.

Mutual Zugzwang

Mutual or reciprocal zugzwang is a rare position such that who ever is to move is in zugzwang, which may occur in late endings ^{[1]}.

Trébuchet

A Trébuchet is an extreme winning/losing type of reciprocal zugzwang in pawn endgames, also broached in Noam Elkies publication On numbers and endgames. ^{[2]}.

Noam D. Elkies (1999). On numbers and endgames: Combinatorial game theory in chess endgames. pdf, differs only in trivial stylistic details from the (1996) version published in Games of No Chance edited by Richard J. Nowakowski

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Home * Chess * Tactics * ZugzwangZugzwangis a position in which it is disadvantageous to move, as every move leads to a worse, and often lost position. Most of the time it happens in late endgames, specially pawn endings, the most obvious example being a KPK endgame, where opposition can be regarded as a special case of zugzwang.## Zugzwang and Null Move

Zugzwang positions are known cause the Null Move Pruning go wrong. For that reason most programs do not use null move in the late endings. As far as middlegame positions are concerned, programmers either assume that they happen too rarely to bother with them, or use some sort of verification pruning.## Mutual Zugzwang

Mutual or reciprocal zugzwang is a rare position such that who ever is to move is in zugzwang, which may occur in late endings^{[1]}.## Trébuchet

A Trébuchet is an extreme winning/losing type of reciprocal zugzwang in pawn endgames, also broached in Noam Elkies publicationOn numbers and endgames.^{[2]}.## See Also

## Publications

^{[3]}1990).Identifying Three Types of Zugzwang. ICCA Journal, Vol. 13, No. 41991 - 2000).Mutual Zugzwang Results. (various) EG1994).Weak Zugzwang: Statistics on some Chess Endgames. ICCA Journal, Vol. 17, No. 21995).A Null-Move Technique Impervious to Zugzwang.ICCA Journal, Vol. 18, No. 21999).On numbers and endgames: Combinatorial game theory in chess endgames. pdf, differs only in trivial stylistic details from the (1996) version published in Games of No Chance edited by Richard J. Nowakowski2001).3-5-man chess: Maximals and mzugs. ICGA Journal, Vol. 24, No. 42007).A Combinatorial Game Mathematical Strategy Planning Procedure for a Class of Chess Endgames. International Mathematical Forum, Vol. 2, No. 682010).6-Man Chess and Zugzwangs. Advances in Computer Games 122011).Zugzwangs in Chess Studies. ICGA Journal, Vol. 34, No. 2## Forum Posts

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## Zugzwang

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## References

1999).On numbers and endgames: Combinatorial game theory in chess endgames. pdf, differs only in trivial stylistic details from the (1996) version published in Games of No Chance edited by Richard J. Nowakowski, MSRI Publications Volume 29## What links here?

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