As a condition, Kevin's power to control this ability is weaker than the Omnitrix, causing the power to overpower his human self causing him to stay as an alien for most of the period. In the episode " Framed," it is revealed that Kevin actually gained the ability to transform into the bodies of the original ten Omnitrix aliens at will, the amount of power produced by the Omnitrix in "Kevin 11" permitted Kevin to completely obtain its powers.
![ben 10 vilgax attacks mr smoothie ben 10 vilgax attacks mr smoothie](https://vignette.wikia.nocookie.net/ben10/images/8/85/Ben_with_Smoothie.png)
In the closing of the episode, Kevin displays the ability to light his hand on fire, suggesting that he absorbed the abilities of at least one of the Omnitrix aliens more permanently.
![ben 10 vilgax attacks mr smoothie ben 10 vilgax attacks mr smoothie](http://vignette3.wikia.nocookie.net/ben10/images/b/ba/Mr.Smoothy_Vilgax_Attacks.png)
The Omnitrix then released a wave of energy sending Kevin through a wall and reverting him to his original form. Kevin realizing, that Ben is now in his own form and powerless against the strength of his current form, grabbed Ben and tried to remove the Omnitrix. Noticing the Omnitrix beginning to time out, Ben desperately fought him back only to have the Omnitrix time out. He and Ben then began to battle, but when the energy from the Omnitrix began to leak out of his body he absorbed more, this time becoming a half- Fourarms creature and he began to overpower Ben. However, Ben, Gwen, and Max arrived just in time to prevent him from killing the gang he had procured the location from.
![ben 10 vilgax attacks mr smoothie ben 10 vilgax attacks mr smoothie](https://i.redd.it/iiaj0idpgqh51.png)
He was bullied by a gang of boys who occupied the The 39th Street Bridge, but when he absorbed energy from the Omnitrix and transformed into a half- Heatblast creature he got revenge and claimed the bridge as his own. He then moved into the streets where he survived by using his abilities. According to Kevin, his parents abandoned him when they discovered that he had superhuman abilities, labeling him a freak.