The Old One is an ancient demonic entity and the main antagonist of Demon's Souls. The Old One takes on the form of a colossal serpentine creature made out of trees and other plant matter. It is many times larger than the Slayer of Demons, the visible part of it being comparable in size to the bridge in front of the Boletarian Palace, where the Archstone of the Small King is located. It appears on a beach in the middle of a vast desert, which is only accessible from the Nexus once the player slays all five Archdemons and talks to the Maiden in Black. It has no facial features other than a circular mouth, inside of which is a passage leading to a small pond which contains the remains of King Allant XII and what appears to be the Old One's, "soul," or, "brain." The Old One is, as its name implies, one of the oldest demons in existence, and is nigh-unfathomably powerful.