Revenant

Revenants are a type of Monster born from the spirit of a deceased humanoid. They are created when a particularly strong-willed individual is betrayed and killed by someone close to them. Unlike Ghosts and Banshees, Revenants retain their physical form, which they are able to regenerate if it is destroyed. They are driven by a single-minded desire for vengeance and cease to exist once they have avenged themselves on their betrayer.