Kevin Levin

Kevin Ethan Levin (otherwise known as Kevin 11) is a prominent character in the Ben 10 franchise.

Appearance
In the original series, 11-year-old Kevin was a thin and scrawny boy with shoulder-length black hair, pale skin, and dark brown eyes with black markings around them. He wore a torn black T-shirt, black studded arm bands, brown cargo pants, black knee-length shoes, and a padlock necklace.

In an Ultimate Alien flashback, 11-year-old looked the same as in the original series, but had his cargo pants replaced with jeans.

In Omniverse flashbacks, 12-year-old Kevin looked the same as before except for his pants being colored grey and his padlock necklace being marked with an "11".

In the first two seasons of Alien Force, 16/17-year-old Kevin grew into a tall and muscular young man. He wore a black T-shirt over a grey long sleeved shirt, blue pants, and black shoes, and had his hair styled into a choppy mullet. He retained this appearance throughout Ultimate Alien.

In season three of Alien Force, he was seen wearing a short sleeved light blue jacket over a white muscular shirt, blue pants, and black shoes. After he went through a mutation, the transformation completely destroyed his clothes except his briefs. As a result, Kevin had to wear an ID Mask to appear human.

In Omniverse, 17-year-old Kevin wore the same black shirt but the sleeves and collar were roughly cut, the sleeves on his long sleeved grey shirt were slightly torn and he wore blue wholesters. His hair was longer and straighter. His pants had a small tear below the left knee. He also wore a padlock necklace similar to the one he wore when he was 11, but marked with an "11". He also sported black discolored marks around his eyes, making him appear tired; these marks bore similarity to when he was 11 and still absorbing energy.

Beginning in "Many Happy Returns", Kevin grew a few chin whiskers and his grey shirt gained stripes. In "Weapon XI: Part 2", Kevin gained the same cross-shaped scar to his chin that his counterpart from Ben 10,000's timeline has.

In the 2016 reboot series, Kevin looks mostly the same as in the original series except that his eyes do not have marks around them, he does not have arm bands, and wears blue jeans, black shoes that are red at the bottom, and a brown Omnitrix-type device called the Antitrix on his left wrist.

Personality
When Kevin first appeared in the original series, he quickly became one of Ben Tennyson's most notable enemies. However, he reformed in Alien Force, and became one of the main heroes. In this continuity, he is an Osmosian capable of absorbing energy, matter, and DNA.

In the reboot, Kevin is a semi-antagonist introduced in season 3, as he is an enemy to Ben in certain episodes and an ally in others. In this continuity, he is an ordinary human equipped with a replica Omnitrix called the Antitrix that he generally uses to fight Ben out of pride and jealousy.

Mutations
Kevin as undergone multiple mutations, most of which involved using his powers on the Omnitrix.

Kevin 11
Kevin's first major mutations occurs in the original series episode "Framed" when his powers got out of control. This form, dubbed "Kevin 11", mostly resembled a reddish-pink Tetramand but with an upper left arm resembling a Pyronite's, an upper right arm resembling that of a Petrosapien, and lower arms resembling that of a Vulpimancer.

Kevin 11 had Lepidopterran wings, a Kineceleran tail, an Ectonurite eye track on his chest, and an upper back resembling a Galvanic Mechamorph. His head consisted of Kevin's hair and ears, two left eyes similar to those of a Tetramand, a right eye similar to that of a Galvan, and the lure, teeth, and gills of a Piscciss Volann. He wore cargo pants in the original series, but switched into jeans prior to an Ultimate Alien flashback, according to Dwayne McDuffie.

In a flashback featured in the Ultimate Alien episode "...Nor Iron Bars a Cage", Kevin was stuck in this form until a Null Void prisoner named Kwarrel taught him to control his anger and master his powers, resulting in Kevin reverting into human form.

Mutant Kevin (young)
Kevin's second major mutation occurs in a flashback in the Omniverse episode "Weapon XI: Part 2" when he uses his powers on the Omnitrix during a fight with Eye Guy.

12-year-old Mutant Kevin's appearance was similar to, yet different, from Kevin 11. His face retained Kevin's structure and hair, but had green skin colored like a Florauna, a right eye similar to that of a Loboan, a left eye similar to that of an Opticoid, a mouth similar to that of a Gourmand, and a head fin and eyes on his chin similar to that of a To'kustar.

His body mostly resembled an Arburian Pelarota's, but with a Polar Manzardill's back and fins, a Splixson's lower chest and sensory nodes, Thep Khufan bandages, and Transylian shoulders. His arms had lower parts resembling an Arburian Pelarota's and upper parts resembling a Transylian's with red Opticoid eyes, Florauna-like spikes, and fingers resembling Florauna tentacles. He also had Splixson legs, Florauna eggplant bombs, and a Gourmand tail in a length similar to Wildvine's tentacles. He wore Kevin's pants and a Thep Khufan crown.

12-year-old Mutant Kevin was reverted after being knocked out by Argit before being taken back to the Null Void by the Amalgam Kids.

Mixed Material Kevin
Kevin's third major mutation occurs in the Alien Force episode, "Vengeance of Vilgax: Part 1", when Ben's attempt to hack the Omnitrix goes wrong, and the Omnitrix becomes overloaded. Kevin runs over to help Ben and tries to override the system, but does not get there in time and gets caught in the feedback released from the Omnitrix. The blast alters his Osmosian DNA with those of various aliens in the Codon Stream.

Unlike his other mutations, Kevin retained his original frame yet his structure was made out of common elements. The right half of his face, the left half of his chest, the upper right half of his chest, part of his back, and his left arm were made of concrete. The lower right half of his chest, part of his back, his stomach, and his right arm were made of metal. The left half of his face was made of Taydenite, and his legs were made of wood.

Kevin turned back to normal in "The Final Battle: Part 2" when the Omnitrix was destroyed. Max Tennyson pointed out that the Omnitrix's energy that had kept him in that form, meaning that his DNA would not have restored itself so long as the Omnitrix was functioning.

Ultimate Kevin
Kevin's fourth major mutation occurs in the Ultimate Alien episode "The Forge of Creation" when he absorbs DNA from the Ultimatrix to stop Ultimate Aggregor from absorbing the powers of a newborn Celestialsapien. He easily drains Ultimate Aggregor's powers, reverting him back into his original form, and then left the Forge of Creation.

Ultimate Kevin's composition was more complex than his earlier mutations from his youth. His face mostly resembled an Aerophibian's, but with Kevin's hair, a patch around the right eye resembling an Evolved Vaxasaurian, and a jaw similar to that of an Evolved Arachnichimp but with an interior resembling that of a Sonorosian. His torso resembled a Vaxasaurian's, but the backside was colored like an Aerophibian and had a set of Necrofriggian wings.

His right arm mostly resembled a Petrosapien's but with two Crystalsapien crystal spikes on his shoulder and a claw similar to that of a Biosovortian. His left arm mostly resembled a Methanosian's, but with a Biovosortian spike on his shoulder and an Appoplexian's wrist claw. He had an Aerophibian-like right foot and an Appoplexian-like left foot.

Ultimate Kevin also had a Vaxasaurian tail, two Cerebrocrustacean legs in place of a secondary left arm, a secondary right arm resembling an Arachnichimp's, and Orishan water ports.

Ultimate Kevin was cured in "Absolute Power: Part 2" thanks to the efforts of Ben, Gwen, Cooper Daniels, and Darkstar. However, Darkstar betrayed Team Tennyson and became Ultimate Darkstar by absorbing Ultimate Kevin's powers from the Dominus Librium. Fortunately, Ben anticipated this and presses a button that stripped Morningstar of his new powers.

Mutant Kevin (teenage)
Kevin's fifth major mutation occurs during the present-day portion of the Omniverse episode "Weapon XI: Part 2", when he uses his powers on the Omnitrix during a fight with Gutrot, Kevin uses his powers on the Omnitrix.

17-year-old Mutant Kevin's face resembles that of a Gimlinopithecus, but with red eyes, Kevin's hair, a Vladat-like mouth, a crest belonging to both a Gimlinopithecus and an Insectoid, and Conductoid antennae.

He has an upper right arm resembling a Segmentasapien's, an upper left arm resembling a Galilean's, a lower right arm resembling a Pturbosaurian's, and a lower left arm resembling an Atrocian's but with sharper claws. His torso mostly resembles a Gimlinopithecus's, with pieces of both Segmentasapien and Galilean near the shoulders.

He has a uneven set of wings, with the left wing resembling a Nemuina's and the right wing resembling a Pturbosaurian's, and Orthopterran legs. He wears pants resembling Kevin's Rooter uniform.

Compared to his other mutations, Kevin has better control over this form, as he intentionally betrayed Servantis, freed the Amalgam Kids from his mind control, and willingly reverted back to his conventional form.

Monster Kevin
In the reboot episode "Which Watch", Charmcaster uses her spell book to turn Kevin into an amalgam of all 11 of his Antitrix aliens, credited as "Monster Kevin". Since Duncan Rouleau has confirmed that each of Kevin's aliens is mutated fusions of two species, Monster Kevin is comprised of a total of 23 different species. including human, Tetramand, Pyronite, Kineceleran, Subsapien, Arburian Pelarota, Galvanic Mechamorph, Galvan, Cascan, Florauna, Lepidopterran, and an unnamed husky-like species.

His head resembled Kevin's but had eyes resembling Quad Smack's with pupils similar to Dark Matter's, a mane resembling Bashmouth's, and a goatee resembling Quad Smack's. His general skin color was purple, and his torso resembled Quad Smack's but with six arms rather than four.

His upper shoulders resembled Crystalfist's, with the upper left arm also resembling Crystalfist's while his upper right arm was a purple version of Hot Shot's. His middle left arm resembled Thornblade's while his middle right arm was a purple version of Bootleg's. His lower left arm resembled Undertow's while his lower right arm resembled Dark Matter's. He also had Wreckingbolt's back, purple versions of Skunkmoth's wings, and had giant version of Rush's tail in place of legs.

Kevin was returned to normal after Humungousaur and Gwen tricked him into using his Pyronite fire breath on Charmcaster's spell book, destroying it beyond usage.

Secondary Mutations
In "Kevin 11", Kevin absorbed some of Heatblast's DNA and temporarily became half-Pyronite, with his left arm and lower body remaining unaltered, and his upper right chest, head, right arm and shoulder resembling that of a Pyronite.

Later in the same episode, Kevin absorbed some of Four Arms' DNA and temporarily became half-Tetramand. While his hair and lower body's clothing remain unaltered, his skin turned red and his arms enlarged and gained black fingernails on each hand. Four holes were on the sides of his shirt, allowing for four thin human-proportioned arms to extend through. He also gained Tetramand eyes and crooked teeth.