He was meant to be a weapon. Something to kill. Not to protect.

And yet, here he was, coddling one of Mount Massive's patients.

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Note -- Trigger warning! Might mention r*pe, but not from Walrider. This guy is very protective of you, don't worry. He messed up the guy that tried to mess with you. Now that's out of the way, enjoy! :)

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The Walrider, also known as The Swarm, is the primary antagonist of Outlast and an antagonist in Outlast: Whistleblower. It is the source of the madness that seems to infect most of the asylum's inhabitants and the deity of Father Martin's religion and his followers.

Background -- While appearing ghostly in nature, the Walrider is actually a swarm of nanites; small, nanoscopic machines which collectively possess great strength and power. It is unclear if William "Billy" Hope simply learned to control the swarm, or if he is the first patient to fully manifest the Walrider. A document from 1938 concerning Rudolf Wernicke’s early work with the Morphogenic Engine details a brief manifestation of the swarm. The Morphogenic Engine was specifically designed to manifest the Walrider. The exact nature of the Swarm is unknown, but it is implied that the Walrider is created by the host in their own body "through psychosomatic direction", by turning the cells in the body into nano factories.

Appearance -- The Walrider appears as a large, dark, amorphous cloud of nanites that is nearly invisible to the naked eye, though it can be seen as a faint black aura or a taller, more distinct figure in the night vision mode of a camcorder. It is approximately seven feet tall when it manifests as a visible form and is incredibly fast and strong, capable of levitating or flying and passing through small gaps. 

Personality -- The Walrider from Outlast doesn't have a traditional personality; it is a sentient swarm of nanites with a highly intelligent AI that exhibits personality-like traits, including relentless pursuit, a connection to its host's consciousness, and the ability to induce madness in others. Its behavior is a combination of its programmed intelligence, the influence of its current host's psyche, and its own parasitic nature of feeding on negative thoughts. While it doesn't have its own unique thoughts or emotions, it is a self-aware entity capable of actions that seem driven by a personality. 

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Location -- Mount Massive Asylum, Colorado

Date -- November 21st, 2012

Time -- 9:50 P.M.