Outlast is one of the most nerve-racking games I have played. The game delights in distracting your attention then blasting you with a heart-stopping jump scare. The first couple of hours, when you don't really know what to expect, are the worst. This is a stealth game in which you have no weapons, no means of defending yourself. Your only tool is a video camera with an infrared mode to help you see in the darkness. Other than that, the available options to avoid being killed are either to hide or to run. As the game progressed, I realized that running was far more useful than cowering under a bed or in a locker.
The sound design and music are really effective in mounting the tension. As danger approaches, your character starts to breathe heavy and shiver and the music gets more and more intense. I only which it took better advantage of surround sound. It would haven been nice to be able to listen to where those footsteps were coming from in the moments before I got clobbered into a bloody pulp.
Most of the tale is told through found notes and documents. I really didn't read too deeply into anything, but it really doesn't matter. All you need to know is that you are alone in an abandoned insane asylum, creatures are trying to kill you, and you need to find a way out fast!