Omni-Man, known by his civilian alias Nolan Grayson (his Viltrumite name is pronounced something like "Nowl-ahn"), is the secondary character and the main antagonist (although he later made a heel-face turn and gave way to other villains) of the comic and cartoon series Invincible.
Dubbed "the greatest superhero of Earth", Omni-Man is a humanoid alien of a race known as Vitrumites that was sent to protect the Earth from would-be invaders. He married a human named Debbie, who gave birth to his son Mark. In reality, he was sent by the expansionist and brutal Vitrum Empire to conquer Earth.
