Among all of Ben's enemies, Kevin is the only one who holds a personal grudge against him.


From all of the visible appearances as a disobedient adolescent, Kevin 11, (voiced by Michael Reisz during his first appearance and Charlie Schlatter in his following appearances and so forth) is a sociopath that Ben encounters after having a quarrel with his grandfather.


Kevin is a mutant human teenager born with the power to take in any sort of power and let go of it whenever he desires. The energy can be utilized to turn on or overwork different types of technology and can be utilized to create energy explosions. When he was taking in the energy from the Omnitrix's aliens, even though he transforms into a incomplete versions, it is still effective. When he makes his first show in "Kevin 11", he soaked in the powers of Heatblast and Fourarms, utilizing the previous appearance's abilities to get even with people whom had wronged him. He extracted the later appearance's abilities once more when he was locked in combat with Ben for the second time to get even again. When he tried to remove the Omnitrix from Ben, the Omnitrix released a reaction pulse to prevent Kevin from winning it, deactivating his power. Kevin, on the other hand, shows the power to produce fire during the conclusion of the episode.


Kevin's main role was to serve as the main villain during several of the second season episodes. His shows the ability to throw fireballs during the end of "Kevin 11" as an affect from the Omnitrix's response pulse: the amount of power it produced permitted Kevin to completely obtain its powers, providing him access to the original ten alien forms that Ben had when they met. 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. Ad shown in the episode, "Framed", Kevin holds Ben responsible for this, so he utilizes the advantages of the Omnitrix powers to make more trouble for Ben, both for his own advantage and to harm Ben's (more like, his alien forms') status.


Sooner or later, Kevin's power to control this ability stopped working in total, changing him into permanently mutated amalgam, what Vilgax would explain as a "misshapen, chaotic amalgam of creatures from the Omnitrix."
This form has:

• Fourarms's head, body, right eyes, number of arms, and legs
• Grey Matter's left eye
• Upgrade's upper back
• Stinkfly's wings
• Diamondhead's top right arm
• Heatblast's top left arm
• Wildmutt's bottom arms
• Ghostfreak's lines on the chest and on his back
• XLR8's tail and speed
• Ripjaws's antenna, gills, and jaws

Right after a short fight with Ben, who is transformed as Fourarms, Kevin was shot off the Golden Gate Bridge from a laser released by one of Lt. Steel's crew.

After his transformation into a mutant, Kevin states that he now has every single one of Ben's alien abilities including his very own, calling himself, "Kevin 11". Even though Kevin states that, Ben takes note that Kevin's new found powers are not as well as his full version (he notes that they are only one-tenth as strong as the real ones, but this may not be a correct evaluation) and Kevin hasn't shown any signs of his original powers in this state, or any those of Ghostfreak, Grey Matter, Wildmutt, or even Upgrade too. Kevin's transformation also restricts his ability to utilize the special skills of the original alien forms. Being a mixture of Omnitrix aliens, Kevin only gained access to the skills most common in his condition. In addition to these restrictions, Kevin 11 doesn't seem to be able to utilize the powers of any aliens that Ben has obtained since the last time they met.


He makes his way into another appearance in "Grudge Match", Kevin was in combat with Ben, to get back at him, blaming his state on Ben. As they fight, Kevin and Ben were teleported and were told to fight in alien gladiator games. Throughout their fight, Ben helps Kevin to learn the advantages of being an amalgam. Because Kevin is a mixture made up of different Omnitrix alien's body parts, he can combine their abilities to make up for their decreased strength. Even thought they were forced to work as a team, Kevin's only achievement was to destroy Ben. In the end, he was brought to another galaxy while fighting Technorg.


Kevin makes his fourth appearance in the second season episode, "Back With a Vengeance", where he works together as a team with Vilgax to overpower Ben, and was able to finally remove the Omnitrix from Ben's wrist. However, he becomes disloyal to Vilgax and tries to abandon Ben and Vilgax in the Null Void, but was unsuccessful causing only Ben to flee leaving him and Vilgax trapped as a substitute.
During one of the fourth season episodes called, "Ken 10", Kevin 11 returns after being trapped in the Null Void for at least twenty years, only to be released by his son, Devlin. He now has control over his powers causing his to be able to return to his human self. In his human form, he can use the powers that he extracted from the Omnitrix alien's DNA to a limited extent, for example, XLR8's speed. His mutated state, yet, still an amalgam, has changed often because of his growing extraction of alien DNA, making him a new title known as "Kevin 11,000". He still obtained Wildmutt's bottom arms, Stinkfly wings, and Fourarms' legs, apart from that he now also has:

• A Heatblast-similar head, body, left wing and right tentacle, but black and yellow instead of the usual red and yellow.
• A left tentacle that splits in the center of Fourarms's left arm and a tentacle with an Upgrade and XLR8's tail marks
• Few gray tentacles (like the tentacles of the flying aliens that appeared in the episodes "Truth" and "Back With a Vengeance") sticking out of his lower body.
• Avalible to emit sonic howls similar to Benwolf's and Zs'Skayr's Minions
• Wildmutt's bottom arms
• Stinkfly's right wing
• Fourarms's legs and the number of arms.

Interested more in revenge than his son, even though Devlin Levin played his part for releasing him, Kevin continues to take on Ben and his Ben's son, Ken . Unluckily, it was his own son that puts a stop to his father, imprisoning his own father in the Null Void once more.
In the first Ben 10 video game released, Ben 10: Protector of Earth, Kevin 11 shows up, but only as a mini-boss that Ben must battle during the end of the Lumber Mill level.

Kevin 11 (Villain) First Appearance
Kevin 11 (Episode)

Kevin 11 (Villain) Last Appearance
Ken 10


See also: Kevin Levin, Kevin 11, Images