Outlast follows a journalist protagonist investigating an asylum who has gone bonkers without spoiling much and your only weapon is a video camera! This means that you won't be able to fight your enemies, you only have 3 options at your disposal, you either run for your life, you hide wherever you can, or you die and in Outlast you will die A LOT!
The FPS view serves as a very personal experience and thus the fear factor goes all the way up. Sometimes its' very dark to play without your night vision cam on, so maybe that can put off some players, but personally I think it adds up to the ridiculous amount of tension you experience when a bloody oversized man, dragging chains chases you along the dark and narrow corridors throughout the game, it can get pretty freaky and claustrophobic. I don't want to spoil much but, I played through the game after finishing Resident Evil 7, which is a more recent game (and a brilliant one too) and I must say you get scared much more in Outlast to tell you the truth, it's such a creepy game, you definitely will remember this game.
The graphics are quite good, I like the night vision effect, there are lots of bloody corpses, gore and guts all over the place so it's not for the faint of heart. The audio is top notch, I played through the whole game with my headphones on, volume turned up, and it's so bloody good, you can hear your character breathing heavily whenever there is a gruesome scene, or someone's chasing you, awesome sound effects.
Gameplay wise, when you think about it, there is not much to do except run for your life, hide, and find documents that serve as background story so you can MAYBE understand some of the craziness and the mentally ill beings that populate the game, and there's the occasional 'find the key' or 'turn the valve' puzzle in order for the player to proceed.
Overall I would recommend Outlast to all the gamers who enjoy a good scare, particularly the horror freaks and the 'adults' who think they don't fear anything or anyone. I'll bet they'll scream like little girls at one point or another.