- Published 2016 in ArXiv

We classify the computational complexity of the popular video games Portal and Portal 2. We isolate individual mechanics of the game and prove NP-hardness, PSPACE-completeness, or (pseudo)polynomiality depending on the specific game mechanics allowed. One of our proofs generalizes to prove NP-hardness of many other video games such as Half-Life 2, Halo, Doom, Elder Scrolls, Fallout, Grand Theft Auto, Left 4 Dead, Mass Effect, Deus Ex, Metal Gear Solid, and Resident Evil. These results build on the established literature on the complexity of video games [Vig14, ADGV14,For10,Cor04].

@article{Demaine2016TheCC,
title={The Computational Complexity of Portal and Other 3D Video Games},
author={Erik D. Demaine and Joshua Lockhart and Jayson Lynch},
journal={CoRR},
year={2016},
volume={abs/1611.10319}
}