Remy: Amnesia: The Dark Descent – First Creature
What makes this game work so well is the fact that it leaves its player completely helpless. You have no means of attack, and can only run and hide when these horrible abominations find you. It is completely terrifying, and makes playing this game an undeniably nerve wrecking experience.
At no point is this more glaringly obvious than when you encounter your first creature in Amnesia. From the way it looks to the fact that you have no way to defend yourself, there is a reason there are tons of reactionary videos on Youtube of people playing this game and screaming like children – because it really IS that scary.