Mordo leaves the palace shortly afterwards and Stephen becomes the Ancient One's successor under the name Doctor Strange. The Ancient One often assists Strange. But when the extra-dimensional monster Shuma-Gorath tries to invade Earth through the Ancient One's mind while the latter is in the Crypts of Kaa-U, the Ancient One prompts Strange to destroy the portion of the Ancient One's mind in which the ego, or sense of self, exists. While such action blocks the way for Shuma-Gorath, trapping him within the Ancient One's mind, the Ancient One's physical body is also destroyed. The Ancient One's corporeal existence is over, but his soul subsequently achieves transcendence, becoming one with the universe and Eternity. Strange then inherits the Ancient One's title as Sorcerer Supreme.