The mark first appeared as a tattoo on the back of Aethyr, one of Zod's disciples, when she emerged from the Black Ship. It was subsequently seen both as a representation of Zod's name and a warning of his impending arrival. The mark was notably burnt into the field where Lex Luthor was abducted by Brainiac and the Black Ship, and as a symbol of red light projected from the Fortress of Solitude that contained Zod's essence.