|Kevin Ethan Levin|
|Species|| Human/Osmosian (formerly)|
|Affiliations|| The Resistance (formerly)|
|Abilities||Most or all of the abilities of the species he is made up of|
|Voice Actor||Greg Cipes|
|First Appearance||Surprise Visit|
Before his mutation, he had his Omniverse season 1 appearance, but the sleeves of his shirt were not cut, and he had no tear on his pants. He also did not have a padlock or wholesters. He had Kevin's Alien Force/Ultimate Alien head and facial features.
After becoming Ultimate Kevin-21, he now looks like Ultimate Kevin in Ultimate Alien, but his tail has black lines (similar to XLR8). His Spidermonkey arm is replaced with a Crashhopper one, and his Diamondhead arm is made of fire instead of crystal. The two Chromastone crystals on the same arm are now made out of building blocks. His left leg is replaced with a Kickin Hawk one.
Prior to his mutation, he had the same personality as his Timeline 1 equivalent, but he was more serious.
After being mutated, he had been broken by the Overrulers and had turned into a mindless servant of Ben-21.
Powers and Abilities
Prior to his mutation, he had all of a regular Osmosian's powers.
After being mutated, he currently has the abilities of over 60 Omnitrix aliens.
After the destruction of Bellwood, he refused to join Ben-21's regime, stating he did not want to return to the dark side. He and Gwen-21 started gathering some of Ben-21's old allies and enemies to take a stand against the regime.
Ben 10: Protector of the Omniverse
- Credits for the human Kevin-21 go to The Awesome Jack.
- Credits for Ultimate Kevin-21 go to Brywarrior.