Thulsa Doom is a fictional character first appearing in the Kull short story "Delcardes' Cat" by Robert E. Howard. He has since appeared in comic books and film as the nemesis of Kull and, later, one of Howard's other creations, Conan the Barbarian. Thulsa Doom is the prototype for many of the future undead evil wizards, such as Tsotha-Lanti and Kathulos; other living or revenant Howardian practitioners of magic such as Thoth Amon, Thugra Khotan, Kathulos and Xaltotun bear some psychological similitudes to Thulsa Doom even if their outward appearance is vastly different.