The character was created by writer Stan Lee and artist Steve Ditko, and first appeared in Strange Tales #111 (August 1963).

Baron Mordo is a gifted magician, especially adept in the black arts of magic, including summoning demons.

[2] The Baron Mordo character has appeared in other forms of media, such as animated television series, films, and video games.

[4] Baron Mordo first appeared in Strange Tales #111 (August 1963), and was created by Stan Lee and Steve Ditko.

[5][6] A Transylvanian nobleman (born in Varf Mandra), Karl Amadeus Mordo became a student of the Tibetan sorcerer known as 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.

Pleased at Strange's unselfish decision, the Ancient One's magical teachings immediately freed the doctor and explained the full situation.

He sent his astral form to hypnotize the Ancient One's servant into poisoning his food, hoping the old man would reveal his secrets of magic.

[10] However, Strange tricked him into returning to his physical body after engaging in astral contact with him, thus breaking his hold over the servant, who helped the Ancient One to recover.

[15] Mordo made a deal with his new master, the demonic Dormammu of the Dark Dimension, to amass additional power to defeat Doctor Strange.

[10][6][16] He dispatched agents, other evil magicians around the World and Spirit wraiths, to search for the incognito Strange,[17] and then banished him from the Earth.

[32] Mordo eventually contracted terminal cancer as a side effect of his use of black magic, and renounced evil just before his death.

[34] He later allies with Terrax, Tiger Shark and Red Hulk as the "Offenders", to be opposed by his old rival and newly costumed Doctor Strange, aided by the other three original Defenders.

[36] During the "Dark Reign" storyline, Quasimodo researched Baron Mordo for Norman Osborn and recommends offering him small favors in exchange for his magical expertise.

Mordo heads to the Sanctum Sanctorum and attacks Wong with Doctor Strange confronting him and the two briefly battle before the latter is taken by Nightmare.

[41] During the "Secret Empire" storyline, Baron Mordo becomes the caretaker of Manhattan after it is surrounded by Darkforce following Hydra's takeover of the United States.

He can tap extra-dimensional energy by invoking entities or objects of power existing in dimensions tangential to Earth's through the recitation of spells.