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arXiv · 2610.23639

Puzznic is PSPACE-Complete

Jake Anderson·Lars Magnus Hvattum·András Z. Salamon
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Abstract

We prove that deciding solvability of Puzznic, a falling-block puzzle game originally developed by Taito, is PSPACE-complete. To show hardness we construct a self-closing door gadget using Puzznic's game mechanics. For membership, we show that the configuration space is exponentially bounded and apply Savitch's theorem. We also improve an existing NP-completeness proof for a simpler version of the game known as Cubic, showing that this game is NP-complete even when restricted to only two kinds of blocks.

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Jake Anderson, Lars Magnus Hvattum, András Z. Salamon. 2026-10-16. Puzznic is PSPACE-Complete. https://arxiv.org/abs/2610.23639

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