More monsters

[Razalhague]

I voted for demons, spirits, Behemoths, shadows and Unimaginable Horrors From Beyond Time and Space, though I don't think demons, behemoths and horrors should be in the game as enemies (not directly). They should be more like lurking in the background and making an appearance occasionally, kind of like the rock worms in Penumbra. Alternatively they could just be the cause of all the things that are happening and you never actually see them. Games that let you directly fight those kind of enemies aren't really horror anymore.