Quoridor is PSPACE-Complete

Marius Drop; Benjamin G. Rin; Finn van der Velde

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arXiv · 2605.22747

Quoridor is PSPACE-Complete

Marius Drop·Benjamin G. Rin·Finn van der Velde

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Abstract

Quoridor is an award-winning abstract strategy game designed by Mirko Marchesi and published in 1997. Similar games include Maze Attack, Blockade (also known as Cul-de-sac), and Pinko Pallino. In line with chess, checkers, Go, and other classic combinatorial games, Quoridor is a turn-based, deterministic, perfect-information game played on a square grid. We show that it is PSPACE-complete to determine whether a given player has a winning strategy in a given Quoridor position on a board with size $n \times n$. We prove this by reduction from Gpos(POS CNF), a Boolean formula game originally defined in 1978 by T. Schaefer.

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BibTeX RIS

Marius Drop, Benjamin G. Rin, Finn van der Velde. 2026-05-21. Quoridor is PSPACE-Complete. https://arxiv.org/abs/2605.22747

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