No one knows exactly how Avatars of Vengeance form. Some claim that when a person with a great need for vengeance dies, their spirit becomes an avatar of vengeance. This story cannot be true, though, as avatars of vengeance are not undead creatures. Rather, they are beings composed of the raw energy of vengeance and vendetta; they are revenge given physical form.
Avatars of vengeance are rarely encountered naturally, nor are they summoned. They are born of a terrible wrong or bitter emotional state. When an individual seeks vengeance with all of their will, they may inadvertently bring to life an avatar of vengeance. The spirit has a will of its own — even if the individual who created it remits their hate. The spirit does not stop until it claims vengeance upon the perpetrator of the act that caused its creation.