Celeste is PSPACE-hard

TL;DR

This paper proves that the platform game Celeste is computationally very complex, specifically PSPACE-hard, under various game mechanics, even in scenarios without player input, highlighting its theoretical difficulty.

Contribution

It establishes the PSPACE-hardness of Celeste across multiple game mechanic subsets, including cases without player input, advancing understanding of game complexity.

Findings

Celeste is PSPACE-hard in multiple scenarios.

The complexity holds even without player input.

Different subsets of game mechanics do not reduce the game's computational hardness.

Abstract

We investigate the complexity of the platform video game Celeste. We prove that navigating Celeste is PSPACE-hard in five different ways, corresponding to different subsets of the game mechanics. In particular, we prove the game PSPACE-hard even without player input.