Omni-Man, also known as Nolan Grayson, is a member of the Viltrumite Empire and the protector of Earth. As a Viltrumite, he possesses superhuman strength, speed, stamina, flight, near-invulnerability, accelerated healing, and extraordinary longevity. These powers make him one of the most formidable beings in the universe.
On Earth, he initially presents himself as a devoted husband and father, as well as a superhero dedicated to protecting the planet. However, his true mission is to prepare Earth for eventual annexation by the Viltrumite Empire, a brutal and expansionist alien regime that values strength and dominance above all else.