quite a letdown. the level design is kinda weak - there's a lot of narrow corridors and enemy encounters rarely feel very unique as a result - and the excessive puzzles are far-too-frequent pace killers that feel like they're intended to pad out the run time. there's a lot of ideas, but doesn't really explore any of them to much depth - especially the aperture connections and multiple-universe references that are disappointingly dropped about 2/3rds of the way into the game. the military-shooter style for the guns with ADS instead of HL2's usual hipfire is a weird choice that doesn't add anything to my mind, and combined with the pretty broken enemy AI and aforementioned poor level design i ended up tired of the combat and unimpressed by the puzzles. it's a shame, because the aesthetics are incredible, and i gotta give props for the effort to voice act all the characters, even if it's not great in english. entropy:zero 2 clears, i'm afraid

This is an impressive mod for Half-Life 2, with some of the best looking environments made with Source I've seen. It even has a great original score.
The mod has issues though. First, the pacing is weird. 70% of the mod is puzzle solving. I like puzzles but in this case it's a bit too much. They constantly stop you in your progression, and some of them aren't that interesting (like go find a battery or a jerrican to start a generator, stuff like that).
The levels are often too claustrophobic, and you'll bump always against walls and small objects on the ground. This mod is clearly inspired by the Metro series, and that kind of narrow level designs don't work very well with Source. You need more space to move smoothly.

With that said, it's still a good mod that's worth checking out. Despite the issues, it feels like an ambitious project made by a passionate team. It's nice to see a HL2 mod which has completely new environments, and not just the same assets from HL2 recycled.