Unsettling, deceptive and thought provoking. Three words that come to mind when I think of how to describe this game.
I went into it without any reading, just waddling along, and had my mind blown sufficiently. Not by the mechanics, which are standard if not simplistic, though they work, but by the setting, the tone, and the commitment to the theme.
This game knows what it is, and embraces that. It's quite a unique story and it creeped me out quite a bit. I got a certain 1 of 4 endings that made me question myself on a deeper level. How often does a game make me do that? This was great.
I took off a star for a couple of reasons: One, if you're doing any revisions to this, please either lessen or take off the camera shake. I was getting motion sickness (literally, it can be a problem for me sometimes, for example, Wolfenstein the New Order did it too, unfortunately) I find the frequency and amplitude of the shake to be jarring. Each switch, fire of the weapon, door opening... there's a lot of it in the game.
The other reason was the sameness of the scenery. Don't get me wrong, I was actually wowed by the gorgeous BG and parallax on the clouds and sun effect. And the wires, the creepy hands, all of the biblical allusions were great, though I would have loved to see some amount of pallette change depending on the area you're in, it could be used to great effect thematically. (Though I do understand you are going for a barren, metallic wasteland sort of vibe)
All in all, great job, really enjoyed it, and want to play again, but I might wait a bit till my eyes stop being dicks -_- (Seriously I'm not being rude with that, it's just a weird thing I experience, I'm not sure if anyone else has that issue too)