Fear is a personal thing. Like the majority of negative emotions, it's most effective when experienced alone, twisting perceptions and making the world seem darker and more dangerous than it would with a bit of company. When company comes in the form of shambling humanoid creatures infesting a decrepit castle that's slowly being eaten away by an advancing darkness, however, it's not quite so effective in keeping the fear at bay.
Amnesia: The Dark Descent places you behind the eyes of Daniel, a man with, as the title implies, no memory. Waking up in a room in the upper floors of Brennenburg Castle, he quickly finds a note from his former self requesting he kill the old man sequestered deep in the stronghold's subterranean passages. A quick walk, a little light murder, and done. That doesn't sound too bad, and it's not like there's any other option available.
It's apparent from the start, though, that this isn't a job for the faint of heart. The abandoned castle is dripping with an honestly foreboding atmosphere, and the tension starts the second you step foot into its darkened hallways. The lighting ranges from dim to pitch-black, strange sounds perfectly heighten the sense of something terribly wrong happening just out of sight, and the fear slowly but relentlessly overtakes any sense of bravado you may have had when you started. Bad things have happened and it's just going to get worse, and the your path takes you right to the heart of the matter.
The fear slowly but relentlessly overtakes any sense of bravado you may have had when you started.
On top of everything else, Daniel can't fight - leaving running away and hiding as the only defenses against the castle's deadly residents. Thankfully, escape is helped by standard FPS controls, but Daniel's real strength is the amount of control he's got over the world. Whether it's in turning the gears on creaky old machinery, clearing rocks from a passageway, or slamming a door shut in hopes that the beast on the other side will take a few extra seconds to break through, the castle is designed to be played with. Of course, that's mostly via scurrying through the dark from one light source to another as sanity drains away, but still.
Sanity all but replaces health in Amnesia. Daniel isn't particularly robust, but other than clumsily falling off a balcony, there's not a lot that can hurt him aside from the monsters, and they're more inclined to kill than wound. The real problem is sanity, which is in short supply when crouching behind a shelf desperately hoping that the creature patrolling this section of the castle won't venture far enough into the room to see you.
Sanity is worn away by three things: unexplainable events, staring at enemies, and being in the dark. It's easily regained by making progress and solving puzzles, but once sanity bottoms out Daniel becomes much harder to control, making him an easy mark for anything he may run across. Moving at a shamble and bouncing off walls doesn't do much for running away, after all.
Still, if you keep your wits about you it's not hard to survive Brennenburg Castle's horrors. The darkness eats away sanity, but it doesn't do it very quickly, and monsters have a hard time seeing you in the shadows. Tinderboxes can be used to light a single torch or candle, and lamp oil fuels the (logically enough) lamp, but the darkness doesn't destroy sanity fast enough make them very important. The atmosphere is thick enough with tension that it's good to light a torch now and then simply for the comfort it provides, but from a gameplay standpoint your night vision is clear enough that you can go without.
It's easy to cynically rag on Amnesia's gameplay, calling it a small handful of monsters roaming a very large number of rooms separated by the occasional puzzle, but the sense of honest fear it evokes over its perfectly-paced ten hours is unmatched. The puzzles aren't too hard but are satisfying to solve, and they have the added effect of lowering not just the sanity meter but the game's very real tension, so that when the next horrible thing happens it retains its emotional punch. Amnesia: The Dark Descent turns a journey of fear, tension, and even revulsion into an incredible gaming experience, and can stand tall beside the best the survival horror genre has to offer.