Helltaker is a game that is free on Steam, runs on Linux, and can be completed in an hour.
@sir first time I've ever heard it described without sharply dressed demon ladies
I do not use steam and the maker of this does not seem to have a self-published version.
As an amateur FOSS gamedev I use Itch, though i don't particularly like it either since it still has tracking habits and whatnot.
At least it does not force me to have an app or anything on the machine (unlike Steam).
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