Dormammu (/dɔːrˈmɑːmuː/) is a character appearing in American comic books published by Marvel Comics. Created by Stan Lee and Steve Ditko, the character first appeared in Strange Tales #126 (November 1964). He is the extra and inter-dimensional demonic entity and deity brother of Umar and the uncle of superheroine Clea who rules over the Dark Dimension. The character has endured as a recurring antagonist of the superhero Doctor Strange.