A friend of mine told me today that HROT was about to launch on Steam Early Access, after which I spent several minutes trying to figure out what HROT meant without asking for help. I eventually discovered that it's not an acronym but an all-caps title for a new indie FPS set in a small Eastern Bloc country that's suffered some sort of ill-defined disaster in 1986.
HROT is being made by a solo developer, Spytihněv, who says it uses a custom engine, written in Pascal, that imitates 1990s software rendering, "with unfiltered textures and polygon jitter." There's an obvious Quake aesthetic to the whole thing—it's very brown—but I get a little bit of Kingpin out of it as well, and the setting brings to mind a sense of Stalker crossed with Pathologic. Some Steam commenters have also called out its similarities to the 1997 FPS Chasm: The Rift—I haven't played that one, though, so I can't comment.
In gameplay terms, it feels very much like Dusk, the outstanding retro-FPS from late 2018. Dusk publisher New Blood Interactive isn't involved with HROT, but New Blood CEO Dave Oshry acknowleged the similarities in a Steam user review, writing, "Dusk dude drink too myuch vodka." (I don't know if "myuch" is a typo or an attempt at a regionally-appropriate accent, but I'm leaving it just in case.) He also described it in a separate message as "essentially Slav Dusk."
The initial Early Access release includes one episode, called "Kiss Me Gustav," with eight levels, nine weapons, 17 enemies, four boss fights, a new game+ mode, and a horde map. The full version will have three episodes with "tons of enemies, weapons and cool stuff," and is expected to be out in 9-18 months. If you'd like to check it out without commitment (and having given it a spin myself, I definitely recommend it), there's also a single-level demo you can try out for free.