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 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 of all ten of Ben's aliens. While, as Vilgax put it, a misshapen chaotic amalgam ofform of the creatures of the Omnitrix 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 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.

Appearance:
 * Four Arms' frame, arm count, left eyes, legs, head, and torso
 * Heatblast's upper left arm
 * Stinkfly's wings
 * Upgrade's upper back
 * Diamondhead's upper right arm
 * Ghostfreak's track
 * Grey Matter's right eye
 * Wildmutt's lower arms
 * Ripjaws' lure and teeth
 * XLR8's tail

(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, 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 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. 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. He turned back to normal in The Final Battle: Part 2 when the Omnitrix is destroyed in battle. According to Max, the Omnitrix kept him in that form.

Ultimate Alien
In The Forge of Creation, in order to stop Aggregor from absorbing the powers of a newborn Celstialsapian, Kevin had no choice but to absorb the Ultimatrix's powers and turn into as Vilgax would call it a a misshapen chaotic amalgam form of the creatures of the Ultimatrix. He is very powerful in this form, and easily defeated Ultimate Aggregor very quickly by draining Aggregor of his powers. However, his personality has become even worse than it was in the original series. Still, there may be hope for him as he was willing to accept younger Ben's comments unlike when they were kids.

Appearance:
 * Four Arms' skin color around torso, arm count, back and legs
 * Jetray's right foot, half of his face, upper back, right eyebrow, eyes and mouth
 * Diamondhead's upper right arm (with Lodestar's claw)
 * Spidermonkey's lower right arm
 * Big Chill's cloak,wings and antennae


 * Swampfire's upper left arm, and fire blast
 * Half of his face is Ultimate Humungousaur's.
 * Lodestar's left shoulder and right claw (with Diamondhead's skin)
 * Humongousaur's chest, tail and lower jaw (red)

Although Kevin absorbed Aggregor's powers (Ra'ad, Andreas, Galapagus, Bivalvan, P'andor), no apperance or abilities has been shown.
 * Chromastone's crystals on his right shoulder
 * Brainstorm's legs in place of a lower left arm and lighting strike with right arm
 * Rath's left claw and left foot (red) and part of his personality
 * Ra'ad
 * Andreas
 * Galapagus
 * Bivalvan
 * P'andor

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.

Appearance:


 * Heatblast's torso, right tentacle, legs, left wing(all colored black), head flame, and shoulder flame


 * Four Arms' feet and left arm


 * Ghostfreak-esc skull-like face
 * Wildmutt's lower arms
 * Upgrade patterned tentacle jutting out of the left forearm, tipped with the pattern from XLR8's tail, black coloration on Heatblast parts
 * A Null Void Guardian's tentacles and Heatblast tentacle right arm


 * Stinkfly's wings


 * Diamondhead-based right wing


 * Benwolf's sonic howl

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 11,000 has shown the ability to retain certain alien abilites he has absorb while in human form, such as XLR8's super speed).