Kevin 11 is an 11 year old delinquent sociopath with a mutant power that allows him to absorb energy. He uses the ability to commit Crimes, to benefit himself never caring about athor people
- Ben 10 - Kevin 11 has black hair, black shirt, jean shorts, and black shoes.
- Ben 10: Alien Force and Ultimate Alien - Kevin grew into a tall and muscular young man. His eyes now lack the black marks (as his body fully recovered from and stopped absorbing energy). His normal attire is a tight black T-shirt over a grey long sleeve shirt, blue pants, and black combat shoes. His hair, although still long, is styled into a choppy mullet. Occasionally, he is seen wearing a short sleeved light blue oil stained mechanic's jacket over a white muscular shirt, blue pants, and his black combat shoes. After he goes through a second mutation, an unbalanced mixture of various matters, the transformation completely destroys his clothes, except his briefs. As a result, Kevin had to wear an ID Mask in public to appear human. In his second mutation he looked like a mixture of solid materials such as stone, wood, Taydenite, and metal. During Kevin's time as Ultimate Kevin, his appearance is again an unbalanced mixture of various aliens that were currently accessible to Ben through his Ultimatrix.
- Ben 10 Omniverse - Kevin 11 has black hair, he wears a black shirt with sleaves torn off, and wears an orange and light orange striped shirt underneath, he also wears blue jeans and black shoes.