Baron Karl Amadeus Mordo (known as Baron Mordo) is a fictional character appearing in American comic books published by Marvel Comics. The character is depicted commonly as an adversary of Doctor Strange. The character was created by writer Stan Lee and artist Steve Ditko, and first appeared in Strange Tales #111 (Aug. 1963). Baron Mordo is a gifted magician, especially adept in the black arts of magic, including summoning demons. Karl Mordo was studying the magic arts under the Ancient One in Tibet when Dr. Stephen Strange arrived. Strange foiled Mordo's plot to kill the Ancient One, leading to Mordo being cast out and Strange eventually becoming Sorcerer Supreme. Mordo has since clashed several times with Dr. Strange, at times with the backing of the demon Dormammu, briefly even impersonating Dr. Strange. The Baron Mordo character has appeared in other forms of media, such as animated television series, films, and video games. Chiwetel Ejiofor portrays the character in the Marvel Cinematic Universe film Doctor Strange (2016) and an alternate universe version in Doctor Strange in the Multiverse of Madness (2022). Publication history Created by Stan Lee and Steve Ditko, Baron Mordo first appeared in Strange Tales #111 (Aug. 1963). Fictional character biography A Transylvanian nobleman (born in Varf Mandra), Karl Amadeus Mordo became a student of the Tibetan sorcerer known as the Ancient One. When Mordo plotted to kill his teacher, Dr. Stephen Strange learned of the plot. Mordo was forced to cast restraining spells to prevent Strange from warning the Ancient One. In desperation, Strange decided to accept the Ancient One's offer to take him on as his mentor in magic to have some hope of stopping Mordo. The Ancient One, however, was fully aware of Mordo's plot and of Strange's desire to warn him. Pleased at Strange's unselfish decision, the Ancient One's magical teachings immediately freed the doctor and explained the full situation. Thus informed in the face of his recent experiences, Strange agreed to become the Ancient One's apprentice despite the requirement that he abandon his former life. The Ancient One trained him to be a formidable opponent of Mordo. Eventually Mordo was exiled by the Ancient One. Mordo's abilities were similar to those of Doctor Strange, but Mordo was particularly skilled at astral projection and hypnosis, as well as mesmerism. He was more than willing to use powerful black magic and invoke demons, both of which