Great game, I really enjoyed it. I like creepy stuff, and here irregular platform shapes of the first level and that purple stuff already hint at something lovecraftian going on, and when the monster appears, ohhhh that is just awesome. I didn't get what the purple bar on top meant tho.
And I really liked the visual effects - the crystals disappearing, monster dripping that black goo, and so on.
If you wish you could check out (and rate ;) ) my submission, too. I tried to make it a bit horror-ish too, although yours is better in that regard imho.