What was the scariest moment in Amnesia: the Dark Descent for you?

I just got this game about 5 days ago and have been playing it as much as I can get my hands on it and I have almost completed it but I was wondering, which moment was the scariest one for you?What was the scariest moment in Amnesia: the Dark Descent for you?
One of the parts that creeped me out the most was the part where you have to walk through the water and that invisible monster is splashing around and chasing you. That was pretty cool. Also every single hallucination/weird vision that you saw, like monsters walking across doorframes and then dissappearing, the walls breathing. Awesome game :DWhat was the scariest moment in Amnesia: the Dark Descent for you?
The prison was the scariest for me so far... I haven't completed the game yet, so it might change.