|Exponentially Variegated Organism|
|Home World||Rex's Earth|
|First Appearance||Ben 10-Generator Rex: Heroes United|
E.V.O.s (shorten for Exponentially Variegated Organism) are a special type of Mutants living in the Earth from Rex's Universe, the E.V.Os are originating later of Nanite Event, all living beings are infected by Nanites (Plants, Animals and Humans).
The appearance of E.V.O.s are random, but the active Nanites altered their appearance at a Molecular level, and gives a infinity class of powers and abilities. Rex, a notable E.V.O, have the appearance of a common Human, but has mechanical powers, and Bobo a Chimp E.V.O is a normal Chimp but with the ability to speak.
Most E.V.O.s are savage and hostile including Human E.V.Os, but others have reason and intelligence.
- Human E.V.O.s
- Animal E.V.O.s
- Alien E.V.O.s