Diamond in the rough. A kind of outsider piece, as if the modder hadn't actually played Half-Life at all, nor learned any basics of level or encounter design. And yet it's super compelling, I think because of the phenomenal atmosphere - the music and sound design is wonderfully fitting and the visual presentation of these gargantuan levels inspired feelings of alienation I've not felt in a long time from a video game. In Portal, there's the framing of Aperture Science and "testing" that contextualises the surreal, enormous levels, but even this game's repeated visits to some sci-fi hub area don't explain a thing. When a piece of a gigantic machine fell down and destroyed half of a (huge) room I was in, it was a really powerful feeling of smallness. You understand nothing and you're tiny and weak, but you're pushing ahead anyway.

It's not very fun gameplay-wise, with annoying encounter design that spams a lot of enemies in wide open areas with no cover, but given the intensely vibes-based design that comes across, and the unexplainability of almost everything, godmoding or noclipping to progress feels thematically justifiable. The environments and atmosphere are the attraction here, and to my mind they're unlike anything else I've seen in a fangame/mod, so go in for those and don't worry about the shooting or puzzles.