The Doppelganger is a Haunted which has a stronger mental link with Ruvik than average, and therefore transformed into something more similar to him.
Since the Doppelganger first appears at his ancestral home, as well as the similarities between his claws that the claws of Laura (Creature), it is possible that the Doppelganger is a corrupted manifestation of Ruvik's childhood self. While powerful, the Doppelganger is still weak in comparison to the actual Ruvik, hinting that it represents the beginning of his descent into madness.
Doppelgangers appear to be clones of Ruvik, wearing a hood similar to his but lacks any facial feature.
The Doppelganger starts to appear in Chapter 11 and in later chapters, proving to be a quite persistent foe, as it can absorb a considerable amount of damage before dying. The creature only has one, but deadly attack; a piercing screech that summons arms that resembles that of Laura's from the ground, chasing after Sebastian. When the arms reach him, they will pull Sebastian underground and will throw his dismembered body back to the surface moments after, resulting in an instant death.
Doppelgangers can be killed with normal weapons although due to their large amount of health and deadly attacks, it is advisable to eliminate them as quickly as possibly. Grenades or explosive bolts can destroy both them and any nearby Haunted or the player can immobilize them with a freeze bolt and destroy the frozen remains. It is possible, and recommended (as to avoid alerting the other enemies) to sneak behind them and perform a stealth kill. As they are considered a variant of Haunted, they are very vulnerable to fire and can even be dispatched with a match.
- The Doppelganger have Beacon Mental Hospital's logo on the left side of its clothes
- The art book reveals that his initial name was supposed to be Mr. Unknown.