Kevin's Mutations



Kevin's mutations are caused by Kevin's power of absorbing energy, and absorbing energy from Ben's aliens and from the Omnitrix itself. The result of this was a mutation consisting of a conglomeration of all of Ben's original ten aliens.

Original series
At first, in the original series, Kevin simply absorbed power from one alien at time, earning the abilities of those aliens. Later when he and Ben were fighting, Ben walked away causing Kevin to get angry and turn into a mutation of all ten of Ben's aliens. While, as Vilgax put it, a misshapen chaotic a amalgam of creatures of the Omnitrix, Kevin was quite powerful in this form, but only had, or showed, the abilities of the aliens most obvious in his form and they weren't as strong as Ben's pure versions. However, he is capable of mixing the abilities to his advantage, such as using Heatblast's flames and Stinkfly's goo to form an explosive attack, which was Ben's idea. Kevin also proved strong enough to hold his own against Vilgax in a fight, which Ben was incapable of. Kevin dubbed himself, in this form, Kevin 11 (which was both the title of his debut episode and his actual name, Kevin E. Levin). After five years in the Null Void, his human DNA overwrote the alien DNA, causing Kevin to lose this form in the Alien Force timeline but in the Ben 10,000 timeline he'd keep absorbing alien DNA, becoming Kevin 11,000, who is most likely non-cannon.

(Note: While Ghostfreak's powers do not manifest, it's mark on Kevin is the jagged black 'Y' shape in the middle of his chest.)

Alien Force
In Vengeance of Vilgax: Part 1, while Ben was trying to hack the Omnitrix, the Omnitrix overloaded. Kevin tried to help Ben by trying to overide the system, but instead he got blasted by the feedback that the Omnitrix created. He turned into a mutation of every solid material he had ever absorbed. In Time Heals, Gwen tried to turn him back to normal by going back in time and stopping the disaster, but later learned that it had to happen after Charmcaster made Kevin a rock slave.

In Trade-Off, Kevin teamed up with Darkstar to turn back to normal. He succeeds but lost his powers, making him least useful to the team. Gwen finds out what he did and goes after Darkstar. Darkstar then absorbs all of her power, and Kevin realizes the only way to save her is to stop Darkstar. After the fight with Darkstar, he got his ugly mutation back (so did Darkstar), and Gwen was saved. He turned back to normal in The Final Battle: Part 2 when the Omnitrix is destoryed in battle. According to Max, the Omnitrix kept him in that form.

Possible future
In the episode Ken 10, which takes place in one of the possible futures, Kevin escapes the Null Void with the help of his son Devlin and declares that during his time there, he absorbed the power of all other aliens trapped with him, becoming Kevin 11,000.

His son Devlin has the ability to turn from human to a mutated form similiar to Kevin's first at will.

Trivia

 * Kevin's mutations appear to be an Osmosian trait (which he inherited from his father Devin Levin) as the full Osmosian villain Aggregor is shown to be capable of absorbing & assimilating alien DNA which allows him to gain their abilities and causes a slight mutation (though nowhere as extreme as Kevin's). It is possible that Kevin's mutantions are a result of this ability, however Kevin may be unable to control his mutantions either due to inexperience and possibly due to him being only half-Osmosian (though Kevin ll,000 has shown the ability to retain certain alien abilites he has absorb while in human form, such as XLR8's super speed).