Today I revealed the secret of this nasty invisible evil corpse-eating water monster you encounter at the end of the demo. Here's a photo of its horrible terrifying shape:
I now realize that I have seen such a thing many times before. But what could it be?
Maybe some mutated form of Yog-Soggoth as described in the forbidden tomes in Miskatonic University in arkham. A Soggoth is a "bubbling mass" (see the dreadful pages of unfathomed wikipedia). So maybe this thing in the sewers of Brennenburg is just some distant cousin of it who came up the long way from the fabled roots of the mountains of madness.
Or I am suffering from paranoia... Ia! Shub-Niggurath! The Black Goat of the Woods with a Thousand Young!
The other monster guy looks like Dr. Herbert West has visited Brennenburg to perform some experiments. I wonder if there are any other lovecraftian horrors in this game.