Like description says. Full of irritating pitch black hidden passages and some kind of puzzle i couldn't be bothered to solve.

I was actually able to find my way through the map. (Didn't find any of the secrets, though.)

The readme states that the author went for a big trans-dimensional research lab with huge machines, and I'd say he succeeded fairly well, creating a distinct look and feel for the map. It was quite an interesting map to explore.

The puzzle Opus was probably referring to, which also gave me a bit of a headache, requires you to step on some really narrow ledges. I think the puzzle would be better communicated to the player if the ledges looked more traversable, i.e. wider.

And now the big elephant in the room: the darkness. It's one of the key elements in creating atmosphere in the map, that's for sure, and I don't mind that, but when gameplay suffers immensely from that, then you get 1/5 ratings from frustrated players. Important passages are hidden in the darkness, and maybe even more annoyingly, monsters ambush you from the darkness. You don't want to have your players illuminate rooms with your weapons to navigate.

But for me, maybe even the darkness wasn't the worst offender. I disliked the end fight the most, which was unnecessarily difficult. You could also fall into the bottom of the elevator shaft, where your only way out is through grenade jumping.

I understand why people rate this 1/5, but if the lighting was okay, I think this map would probably fall into 3/5 territory. It's creative, has challenging combat and has a lot of effort put into it.

Agree with everything Esrael wrote. This has a unique setting/concept and had the potential to be good.