One of the scariest survival horror games I've ever played.
It's one of the first games I'd truly call survival horror as you don't get any opportunity to destroy those horrifying creatures patrolling the corridors of the abandoned castle. As a fan of H. P. Lovecraft I was glad to encounter many references to his Cthulhu myth and the overall mood of his works (e.g. the protagonist going insane when looking at monsters or standing in the darkness for too long).
Amnesia is perfect in the way it leaves most of its scary parts to manifest in your mind. It takes quite a time to see the silhouette of the first enemy but the unnatural happenings and frightening sounds made me so nervous by then, that I fled desperately, covered in cold sweat.
I hope that the sequel will be just as good as the first game was.