Have tested IG2 two times now (had my sound of for some reason the first time, and figured it out first after I had played the game). Anyway, it was nice but three things would be better to think of to your next game:
1. Better level design.
I entered an door or something at the end of each level, but on the next, there where no sign of where you came from. And I would also recommed you to implement objects like crates that stands on the ground in the large rooms and lamps that lights up around them to make the world more alive and not just an big, flat and quite empty maze. Like tourches that light it up.
2. Harder.
Ok, I do not mean that the enemys should be nearly impossible to kill, rather that they should have better AI and that the puzzles in the game could be made better (not just "find key and open door" or "use this thing to open this door", but rather puzzles that can be hard to solve and that forces the player to really think what they are doing).
3. More animated stuff.
Make more of the stuff you had in the beginning (the intro). Like when you come to the boss, you could talk to her for a short period before hell breaks loose, if you get what I mean.
That´s enough of what could be done better. You have created an game with an good atmosphere. The music and sounds where excellent in combination with the style of the game, and the shaders was really nice. Very well done!
Ohh, and I found an secret room. Who are these two guys?
As an note, there are some other pictures in that room too, so people, try to find it.
Darkness, you haunt me. If I give in, I would be an monster beyond imagining. Light, you guide me. Thanks to you, I see past the nothingness. Life, I choose to live in the light.