The Deviants are not immortal or indestructible. The sole known exception is the Warlord Kro, who, despite being vulnerable to injury, has lived for untold centuries, although he has concealed this fact from his fellow Deviants. Many Deviants possess superhuman abilities. The most common superhuman power among the Deviants is superhuman strength.

The Deviants were the first natives of Earth to develop technology, and even thousands of years ago had already become highly advanced in the study of genetics. It was the Deviants who created the Subterraneans as their slaves, and it has been speculated that it was the Deviants who genetically transformed ordinary humans into the water-breathing Atlantean race.

Originally the Deviants built their cities on the Earth’s surface. They used their advanced technology to conquer the nations of humans, and eventually conquered the entire known world except for the empire of Atlantis.

Since the sinking of Lemuria, Earth’s Deviant population has been greatly reduced from what it was. Because of the Deviants’ distaste for childbearing, they have felt no need to increase their numbers by a considerable degree, and today there are only about two thousand Deviants in the world, most of whom are sequestered underground.