Quake

There's something moving under the surface, a wretched rebirth fighting free, ruptured technology bleeding at the edges, biomechane ripped raw and rotten from the world-engine, trying to fly only for its wings to melt away in fungal froth as it crosses the apex of the eclipse.

The kitsch purple-prose episode-end texts about seizing magic runes from cosmic horrors is the only story you get, leaving levels as diverse as Gloom Keep and the Sewage System and Wind Tunnels and Dismal Oubliette as atmospheric yet opaque toyblock killboxes. Low-key genuinely-disturbing industrial ambience, responsive movement, level design with deathmatch arena sensibilities, and a small but characterful roster of enemies all make it a surprisingly strong game given how rough its dev was, though this design philosophy was kinda left by the wayside as shooters shifted to more-continuous layouts for more-involved stories with more-natural encounters. The tail end of id being (able to present themselves as) the giants on whose shoulders everyone else stands.