Kevin Levin

For a time, Kevin Levin was a villain in the cartoon series Ben 10. In the premiere of Ben 10: Alien Force, he became a hero/anti-hero and joined his former rival / new friend, Ben Tennyson to fight against extraterrestrial activities.

Then on Ben 10: Ultimate Alien episode, The Forge of Creation, he absorbs the Ultimatrix and becomes insane once again and a lot more dangerous than before.

Ben 10
When Ben found him, Kevin lived alone and stole from people in order to get by. Ben befriended him once he found out that Kevin, too, had special powers. Then, when Kevin tried to commit a crime out of spite, Ben tried to stop him and persuade him to use his powers for good. Kevin grew resentful of Ben and later returned as an enemy.

Kevin reappeared in several episodes. In one episode Kevin absorbed the Omnitrix, granting Kevin the power of shape-shifting into Ben's alien forms. Kevin tried to frame Ben for several crimes. But eventually Kevin mutated even furthur into a monster with all of Ben's alien forms wrapped into one hideous creature.

But in one episode, Kevin and Ben had to team up with each other. they were kidnapped by a robot named Slix Vigma. They were forced to fight other as entertainment for others. Because they were connected together. After Slix was destroyed Ben manage to escape while Kevin was trapped on the ship with a new friend of Ben Technorg.

Kevin also teamed up with Vilgax so he can defeat Ben for making a fool out of him. Since then Kevin has been trapped in the Null Void.

Ben 10: Alien Force
In the first episode of Ben 10: Alien Force, Kevin joins Ben and Gwen to battle against evil. Even though Kevin became an ally to Ben Tennyson Kevin still did several things that make him an anti-hero.

Ben 10: Ultimate Alien
It is later revealed in the episode of Ben 10: Ultimate Alien, Ultimate Aggregor, that when he absorbed raw energy, he became insane, which happens to the rest of the Osmosians. Later in the episode The Forge of Creation, he absorbs the Ultimatrix in order to stop Aggregor from absorbing a baby Celestialsapien, but it does more harm than good after he goes insane again. After Aggregor has been defeated, he flies off, leaving both 10 and 16 year old Ben and 16 year old Gwen behind. In the next episode, ...Nor Iron Bars A Cage, It's revealed how Kevin escaped from the Null Void and how he turned back to normal between the original series and Alien Force and how he had gotten his material absorbing powers. In the same episode, he volentarlly goes back to the Null Void to get revenge on his prison's warden, Morgg. He almost got his vendetta on Morgg, and leaves the prison, thinking that he did kill him. Gwen still thinks that Kevin could get his sence back and go back to normal, but Ben says that they now might have to "put him down", meaning that Kevin might have to be killed. However, as of the end of the season one finale episode, "Absolute Power: Part Two", Ben and the others restored Kevin back to normal, and Kevin is once again a good guy.

Powers and Abilities
Kevin has the ability to absorb any solid matter he touches like stone, metal, and crystal, and have it cover his entire body. He is also able to shapeshift his arms when coated in solid matter and repair cracks with a simple touch.

Alternate Reality Kevin
Main article: Kevin 11,000

In an alternate reality, in the distance future, Kevin is still trapped in the Null Void. While he was there, Kevin's been absorbing all the other aliens that were in the Null Void. He somehow manage to produce a son named Devlin Levin, and told him to open the Null Void projector so he can "Spend some time with his son."