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arXiv · 2601.18813

Fog of War Chess

Matthias Gehnen·Julius Stannat
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Abstract

Fog of War chess is a popular variant of classical chess, in which both players have only partial information about the position of the opponent's pieces. This study provides the first theoretical analysis of endgames in Fog of War chess. In particular, we analyze the setups king and queen versus king, king and rook versus king, and king and two rooks versus king. We show that a king and queen can always guarantee a win against a lone king. In contrast to classical chess, a king and a rook cannot guarantee a win against a lone king. However, adding one more rook guarantees a win.

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Matthias Gehnen, Julius Stannat. 2026-01-21. Fog of War Chess. https://arxiv.org/abs/2601.18813

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