Penumbra is real - possible inspirations?

[The Rock Worm]

Thanks. Deep One, that place is scary.
I wish to have an horror adventure game with that locations.

Oh, I almost forgot. This might be something you're looking for:

http://www.moddb.com/mods/crypt

I'm keeping my eyes on this one. Very promising mod.

Oh wow, that is a great mod! I will have to keep an eye on this as well