List of villains in Ben 10

This is a list of villains in the American animated television series Ben 10.

Main villains

Vilgax

Vilgax (voiced by Steven Blum) is a Chimera Sui Generis from the Null Void Frontier. His appearance is also very similar to Cthulhu. A vicious, intergalactic conqueror, Vilgax will stop at nothing to obtain the Omnitrix and use it to build an army capable of conquering every planet in the galaxy. Vilgax serves as the main antagonist of the first season responsible for half of Ben's enemies before appearing in person in the final episode of season one. He is, without a doubt, Ben's most powerful enemy.

In the first season, Vilgax is confined to a regeneration tank after being severely injured by the final attack from Xylene's ship, ordering his robotic minions and cosmic bounty hunters to track down the Omnitrix for him. While his body is repaired, he is cybernetically enhanced, making him more than a match for any Omnitrix alien after finally emerging from the tank. Furthermore, the modifications greatly augment his physical prowess, allowing him to easily to leap above skyscraper heights and smash apart mountains, along with being able to increase his strength at will. Even before his modifications, Vilgax had uncanny resistance to harm, being able to survive a nuclear explosion at point blank. At the end of the first season, Vilgax tries to retrieve the Omnitrix himself, but is fought off by the Tennysons. Vilgax's ship is destroyed with him still aboard.

In "Truth", Max tells Ben and Gwen how he had a run in with Vilgax. Vilgax was stealing warheads from a military base when Max and his partner showed up. In the resulting fight, Vilgax was strapped to a warhead by Max and launched into his own ship.

At the end of the second season, Vilgax is still alive, having survived the destruction of his ship but shot out into outer space somehow. He is found encased in ice by Kevin 11 and the two team up in another attempt to retrieve the Omnitrix, but both are locked away in the Null Void dimension by the end of the episode.

In the episode "Ben 10,000", set twenty years in the future, Vilgax eventually escaped the Null Void but lost yet another battle to Ben 10,000. This time around, Ben 10,000 didn't take any chances with Vilgax's defeat, literally tearing Vilgax to pieces. Dr. Animo revives Vilgax using his Transmodulator and the two of them then attempt to get revenge, only to be defeated by both the present and future Bens and Gwens. Ben 10,000 defeats Vilgax by freezing him in a river. This future isn't necessarily certain, as Ben 10,000 interferes with his own past at the end of the episode, potentially altering events from there-on.

A dream version of Vilgax appears in the episode "Perfect Day", where he appears to confront Ben. The battle lasts for a short time, and then Vilgax tries to send Ben to the Null Void. As Fourarms, Ben throws him in instead, but this proves to be an error on the part of the Forever Knights, as Vilgax was about to send Ben to the Null Void without first obtaining the Omnitrix.

Vilgax appears in Ben 10: Secret of the Omnitrix, where once again he attempts to retrieve the Omnitrix. During a flashback, Tetrax reveals that Vilgax destroyed the Petrosapien homeworld, and he unwittingly gave Vilgax the final element needed to carry out his plan. It is unknown how Vilgax escaped the Null Void, but Vilgax refers to his anger at having spent there (including showing a short nervous twitch at its mention), which has deepened his grudge against Ben to the point where he refuses to acknowledge the danger threatening the universe if the Omnitrix self-destructs (but nevertheless gains enough respect for Ben to the point of calling him his real name instead of Tennyson). After a series of battles, he is defeated when Azmuth, the creator of the Omnitrix, gives Ben access to a massive alien, Way Big, who hurls Vilgax into outer space.

Vilgax returns in "Goodbye and Good Riddance", yet again to steal the Omnitrix. Through the combined efforts of Ben and his father, Vilgax is caught in a gasoline explosion which caused him to be incinerated. It is unknown whether or not he survived, although it is apparent as seen in the episode "Ben 10,000." Vilgax is the main villain in Ben 10: Protector of Earth. After being released from the NullVoid by Ghostfreak, Vilgax sends a small mosquito-like drone to go to the Omnitrix and extract the DNA from it. Using the DNA, Vilgax plans to use the Null Void, plus other Plumber technology, to create a vortex large enough to erase Earth from existence. To stall for time, Vilgax sends Dr. Animo, Ghostfreak, and Floraunas to distract Ben, giving him more than enough time to prepare. However, due to Ben shooting Vilgax through space via airlock, Vilgax is warped back to the Null Void, along with his ship, and presumably the Null Void Projector.

Kevin 11

By all outward appearances a rebellious teenager, Kevin (voiced by Michael Reisz in his first appearance and Charlie Schlatter in his following ones) is actually a mutant with the ability to absorb any type of energy and release it at will. The energy can be used to activate or overload various machines and can also be used to make energy blasts. When absorbing energy from the Omnitrix's aliens, he becomes an incomplete, but effective, version of that alien. In his first appearance in "Kevin 11", he absorbed the abilities of Heatblast and Fourarms, using the former form's powers to get revenge on those who had wronged him. He absorbed the later form's powers during his second battle with Ben to even the odds. After trying to take the Omnitrix from Ben, the Omnitrix emitted a feedback pulse to prevent Kevin from taking it, seemingly neutralizing his power. Kevin, however, exhibits the ability to create flame at the end of the episode.

Kevin serves as the main antagonist of the second season. His ability to project heat at the end of "Kevin 11" is a result of the Omnitrix's feedback pulse: the amount of energy it emitted allowed him to fully absorb its powers, giving him access to every alien form Ben had at the time. As a side effect, however, Kevin's ability to regulate this power is poorer than that of the Omnitrix itself, causing the energy to suppress his human form and forcing him to remain as an alien most of the time. As revealed in "Framed", Kevin blamed Ben for this, so he uses the powers of the Omnitrix to commit crimes, both for his own benefit and to damage Ben's (or rather, his alien forms') reputation. Eventually, Kevin's ability to regulate the power fails altogether, causing him to permanently mutate into what Vilgax would describe as a "misshapen, chaotic amalgam of creatures from the Omnitrix." This form has:

• Fourarms's head, body, left eyes, legs, and arm count
• Grey Matter's right eye
• Ripjaws's esca, gills, and teeth
• Upgrade's upper back and shoulders
• Stinkfly's wings
• Diamondhead's upper right arm
• Heatblast's upper left arm
• Wildmutt's lower arms
• Ghostfreak's eye track
• XLR8's tail and speed

After a brief battle with Ben as Fourarms, Kevin is shot off the Golden Gate Bridge by a laser fired by one of Lt. Steel's men, but due to Ripjaws's gills, he survived under water.

After his mutation, Kevin gloats that he has all of Ben's powers plus his own, making him "Kevin 11" (the name Kevin is credited under in the ending sequence of the show). Despite Kevin's claim, Ben notes that Kevin's powers aren't as good as his pure version (he quips that they're only one-tenth as strong, though this is likely not an accurate assessment), and Kevin never exhibits his original powers in this form, nor those of Ghostfreak, Grey Matter, or Upgrade (The powers he can use are based on which aliens are used very often, hence he has Fourarms's body, arm count, strength, and appearance because Ben uses Fourarms the most), Kevin also seems to forget that he can fly and rarely uses XLR8's speed to his advantage, mainly relying on Fourarms's strength and endurance, Stinkfly's slime blasts, Diamondhead's crystals and Heatblast's pyrokenesis. Kevin's mutated form also limits his ability to use the special powers of his alien forms. Being a random fusion of aliens, Kevin only has access to the powers most prevalent in his form. In addition to these limitations, Kevin seems unable to use the powers of any aliens Ben has gained since their original encounter.

During his third appearance in "Grudge Match", Kevin attacks Ben to get revenge, blaming his condition on Ben. As the two battle, they are abducted and forced to fight in gladiator games. During their battles, Ben helps Kevin to realize the advantages of his mutated form. Because Kevin is an amalgam of aliens, he can mix and match their powers to make up for their reduced potency. Although forced to work together, Kevin's only goal was killing Ben. He is transported to a different galaxy at the end of the episode while locked in combat with Technorg.

Kevin returns in the episode "Back With a Vengeance", where he teams up with Vilgax to defeat Ben, and eventually manages to remove the Omnitrix. However, he betrays Vilgax later in an attempt to leave both in the Null Void, only for Ben to escape and leave him and Vilgax trapped instead.

In "Ken 10", Kevin returns after at least thirty years of imprisonment in the Null Void, having been set free by his son, Devlin. Kevin has now fully mastered his powers and can return to his human form. In his human form, he can also utilize the powers he has absorbed to a limited extent, such as XLR8's speed. His mutated form, though still an amalgam, has changed considerably from his continued absorption of alien DNA, leading to his new title of "Kevin 11,000". In this form, he now has:

• A Heatblast-like head, body, left wing and right tentacle, but black and yellow instead of red and yellow.
• A left tentacle that splits in the middle into a slim Fourarms arm and a tentacle with the markings of Upgrade and XLR8's tail
• Several grey tentacles (similar to the tentacles of the flying aliens featured in "Truth" and "Back With a Vengeance") protruding from his lower body.
• Wildmutt's arms
• Stinkfly's wing pattern (though only the right wing has the same pattern)
• Fourarms's legs
• Yenaldooshi's Sonic Howl

Eager for revenge and having not so much as a care for his son, despite Devlin's role in releasing him, Kevin proceeds to beat on Ben and his son, Ken. Ironically, it is Devlin who stops him, trapping his father back in the Null Void.

In the video game Ben 10: Protector of Earth, Kevin only appears, surprisingly, as a mini-boss Ben fights at the end of Lumber Mill.

Kevin reappears in Ben 10: Alien Force as an ally of Ben's, at least temporarily.

Ghostfreak

Ghostfreak (voiced by Steven Blum) is one of Ben's forms, freed from the Omnitrix. A copy of his evil personality was trapped within the Omnitrix when his DNA was sampled. He finally manages to force his way out of the Omnitrix in "Ghostfreaked Out". For some reason, Ghostfreak goes by the name Ben gives him, and does not mention having a real name. After peeling off the protective layer of skin that normally covers him, he tries to take over Ben's body in order to become whole again. After a failed attempt to possess Ben, he coerces Acid Breath, Thumbskull, and Frightwig to help him by taking over Thumbskull and tossing him about the room in a show of force. After this episode, Ben is no longer able to transform into Ghostfreak. Ghostfreak is later replaced by Cannonbolt in the opening credits at the start of the third season.

Ghostfreak is the main antagonist in the third season, returning in the two-part episode "The Return"/"Be Afraid of the Dark", where he is revived by an alien scientist named Dr. Vicktor (Vicktor's species is stated to be from Anur Phaetos, the Ectonurite homeworld, in Ben 10: Protector of Earth). Gathering a group of horror-themed aliens as minions, Vicktor enacted a plan to resurrect Ghostfreak, whose master plan was to plunge the Earth into darkness, just like his actual home world. Ghostfreak himself is still intent on gaining control of the Omnitrix. Using corrodium retrieved by the mummy alien in "Under Wraps", they set up a corrodium beam that will block out light from the sun, allowing Ghostfreak to exist in eternal darkness. Ghostfreak succeeds in doing so, allowing him to reach his full potential, but only for a while before Doctor Vicktor accidentally rammed Max into the corrodium projector during a dogfight. In the end, Ghostfreak is killed on board a space shuttle, when Max opens the shuttle's roof and exposes him directly to the sun. Ben regains use of the form during this time, except in Ghostfreak's natural state.

Ghostfreak appears in Ben 10: Protector of Earth as the main boss of the North East, and is fought in Gold Coast Theater. While not the main villain, he is the one who frees Vilgax from the Null Void, and instigates the plot. He appears similar to his form in Be Afraid of the Dark, having shoulder spikes and more detailed features.

Ghostfreak's minions

These three aliens appeared in separate episodes during the third season. It is later revealed that they were working together on a complex scheme of Ghostfreak's design. It is never explained how this came about, since Ghostfreak was apparently fully incapacitated throughout the season (the fact that his species think through a hive mind might have something to do with it). Ghostfreak and his minions are all based on horror monsters (Frankensteins' monster, a mummy, a werewolf, and a ghost).

Doctor Vicktor: An alien resembling Frankenstein's monster is a Transylian, Doctor Vicktor works at NASA, disguised as a human scientist as a means to hijack a space shuttle. He is intelligent, and working for Ghostfreak; his immediate plan was to resurrect his master, whose ultimate plan was to prevent the sun's light from reaching the earth using various satellites (therefore meaning that Ghostfreak would be at full power all of the time). He serves as the unofficial leader of the three horror-themed aliens. The purple lightning that the previous two horror aliens appeared in was generated by a teleportation machine that he uses. His name is derived from the name of Victor Frankenstein from the Mary Shelley novel.

His first appearance is in "The Return", where he succeeds in reviving Ghostfreak. In the next episode "Be Afraid of the Dark", Ben fights Vicktor and Ghostfreak on Earth. Ben accidentally gains use of Doctor Vicktor's form when Vicktor finds Ben and grabs him by the wrist, unintentionally adding his DNA to the Omnitrix. Vicktor essentially defeats himself near the end of the episode. In an attempt to teleport Ben to an unspecified location, he and the mummy alien are tossed into the portal he created. Doctor Vicktor is voiced by Michael Dorn.

In Ben 10: Protector of Earth, he is revealed to be a subspecies from Ghostfreak's planet, called Vicktor.

Mummy alien: The Thep Khufan appeared in "Under Wraps", sent by Doctor Vicktor to find a dangerous element called corrodium that crashed on Earth millions of years ago. Grandpa Max explains that the crystals are a potent but unstable power source, and the radiation emitted by the crystals causes almost instant mutation in humans and other Earth-born creatures.

Todd Maplewood, a boy Ben and Gwen met, said it arrived in purple lightning, which is the same way the Yenaldooshi arrived in "Benwolf". Max states there may be a connection between the Yenaldooshi and the mummy alien, which is proven in "The Return".

During Ben's battle with the creature, its DNA is absorbed by the Omnitrix, giving Ben access to the form. The Thep Khufan alien is frozen solid by Upgrade and buried, along with its corrodium, under a thick bed of concrete. It was released by the Yenaldooshi in "The Return", and assists in Dr. Vicktor's plan to plunge the earth into eternal darkness. When Ben is fighting Ghostfreak, Doctor Vicktor, and the mummy alien in "Be Afraid of the Dark", Doctor Vicktor inadvertently sends both himself and the Thep Khufan to an unspecified location through an ill-timed use of his teleportation device. Ben's version of this alien is named Benmummy.

The alien Mummy appears as an enemy in the game "Ben 10: Protector of Earth" as two enemies: Mummy and Cyclone Mummy.

Yenaldooshi: The Yenaldooshi is a Loboan (a species of werewolf-like aliens) sent by Doctor Vicktor to steal communication equipment from a reservation that Ben, Gwen, and Grandpa Max were visiting in "Benwolf". Ben first fights against the alien as Wildvine. When Ben is transformed back to his normal self by the Omnitrix, the alien werewolf slashes the Omnitrix, causing the device to download his DNA (signified by its face turning yellow) and gradually change Ben into the form.

In their second battle, the Yenaldooshi appears to be killed by a cave-in, though it is not actually shown dead. The device that it was building is shown coming online at episode's end, its purpose left unrevealed. The Yenaldooshi is revealed to have survived in "The Return", and its device is used as part of Ghostfreak's plan to block out the sun. In the next episode "Be Afraid of the Dark", the Yenaldooshi's transmitter explodes when Grandpa Max rams a space shuttle into Ghostfreak's corrodium projector, destroying it. It is unknown if the Yenaldooshi survived the explosion of the transmitter, though it is possible that he has somehow ended up in the Null Void, since his Sonic Howl has apparently been integrated into future Kevin's new form.

The Yenaldooshi appears as an enemy in Ben 10: Protector of Earth in two variants: Fangface and Fangface Howler.

The Negative 10

The Negative 10 is a group of villains recruited by the Forever King to defeat Ben in the Ben 10 vs the Negative 10 special, most of which are arch-nemesis of Ben.

The Negative 10 consists of:

• The Forever King
• Forever Knight Ninja, a devoted servant of the King, skilled in single combat
• Dr. Animo
• The Circus Freak Trio (Acid Breath, Frightwig and Thumbskull)
• Joey/Rojo (armed with a new cybernetic suit provided by the Forever Knights)
• Clancy (now having devolved into a giant mutant insect since his last encounter with Ben)
• Charmcaster
• Sublimino (new leader Of The Circus Freaks)

The Negative 10 henchmen are defeated when the Tennysons exploit their competitive feelings towards each other and trap them in the force field which previously stored the Sub-Energy.

Dr. Animo

Dr. Aloysius Animo (voiced by Dwight Schultz) was once a promising researcher in veterinary science. His career was cut short when it was discovered that he was performing twisted genetic experiments on animals. He had hoped that his research would win him the Verties Award, which is an award in veterinary science. Because of the nature of his research, he lost the award to another doctor, named Kelly. This drove him mad, and he dropped off the map for five years until he could perfect his research. In the episode "Washington B.C.", he finally finishes his work. For some reason, his skin is currently yellowish-green. A picture of him on Gwen's computer shows that he had normal skin in the past.

By using the Transmodulator, a device of his own design, Animo can mutate animals into giant versions of themselves. The second phase of his work involves reanimating dead cells, literally bringing dead animals back to life. All of this is in pursuit of the award which he had lost. His quest ends in failure, since Ben was there to stop him, reversing the effects of his Transmodulator by damaging it. He is arrested in that episode.

He appears again in the episode "Dr. Animo and the Mutant Ray", where he creates a much larger version of the Transmodulator using the broken-off faceplate of the Omnitrix. This version mutates living creatures with alien DNA, creating odd mixtures of alien and terrestrial creatures, such as a "Heatbat". Before he can complete his plans to use a satellite to shoot the ray all over the world, Ben stops him with Gwen's help. Since his mutants were never shown being cured, it is possible that they are still around, from then on he attempts to steal DNA from the Omnitrix . For some reason, his trademark giant frog is also present, though he may have simply re-mutated it sometime after his original defeat. How and when he escaped is unknown.

In "Ben 10,000", Animo is still alive, though his head is the only part of him that remains. However, it controls a unique apparatus that allows him to attach himself onto animals specially reformatted with a device (in this case, an albino gorilla) and control them. He was the one responsible for creating Exo-Skull and reviving Vilgax. He is defeated by both Gwen and her future self, Gwendolyn, as well as a cybernetically-enhanced Grandpa Max.

In "Divided We Stand", it is revealed that his first name is Aloysius. He escapes what seems to be Alcatraz Island on a mutant seagull and captures one of Ben's Dittos to access the DNA stored in his Omnitrix. He creates an army of self-replicating Lepidopterran mutants, but they are destroyed and he is captured again.

He also appears in Ben 10: Secret of the Omnitrix, but only as the instigator of the main plot. In it he tries to create a DNA bomb that was designed to devolve all life on Earth. He is defeated and the bomb is disabled, but a stray burst of energy is still emitted by it. Ben's Omnitrix absorbs the energy, causing it to start a self-destruct sequence and therefore beginning the plot. Dr Animo was also mentioned in "Ken 10."

He makes a brief appearance at the end of "Goodbye and Good Riddance", wearing an ape-like exo-suit, and leading a group of animal mutants towards Ben's school. He appears in the following episode, "Ben 10 vs. The Negative 10", as part of the Negative 10. He was then joined by a mutant bat and prairie dog.

Dr. Animo appears in Ben 10: Protector of Earth as the main villain of the SouthEast, and is fought at Oil Refinery. He battles in a robotic gorilla suit, similar to his appearance in Ben 10,000, although the in-game version is obviously more robotic and is merely Animo in a suit, instead of being a disembodied head on a cyborg.

Charmcaster

Charmcaster (voiced by Kari Wahlgren) is Hex's niece. Like Hex, she uses magic, but instead of using a staff, she has a bag from which she can draw all manner of items, such as magical explosives, throwing blades, or even a variety of clay animals which she can enlarge and animate to do her bidding. Although small, the bag seems to have something of a pocket dimension inside (basically a magic satchel), allowing Charmcaster to store things within it that logically should not fit (at one point, she produces Hex's magic staff, an item that is at least four feet tall). The bag also appears to have some degree of sentience, as it found its way back to Charmcaster under its own power. She is also skilled in various magical spells, although it's clear that because of her inexperience, she isn't as powerful as her uncle.

In her debut appearance, "Tough Luck", she busts her uncle out of prison and assists him in trying to steal the Keystone of Bezel. She manages to trick Gwen by putting on an act about hating her uncle, only to swipe the Keystone while hugging Gwen. She then gives Hex the Keystone. In the end it's revealed that Hex needs the Keystone to recreate the Charms of Bezel, and that she is manipulating her uncle into doing it so that she can take their power for herself. In the end, her powers, like Hex's, seem to be absorbed by the Keystone.

Charmcaster returns in "A Change of Face", her powers having regenerated since her recent encounter with the Tennysons. She attempts a body swap spell with Ben, hoping to take advantage of the Omnitrix to boost her spells. Her efforts fail, however, as her three attempts end in swapping with Gwen, being returned to her normal body while Ben and Gwen are swapped, and returning Ben and Gwen to their normal bodies respectively. She is arrested at the end of the episode, and her bag is tossed into the sea. She is last seen in a juvenile detention ward, where she is about to be beaten up by two female inmates whom Gwen spurned while she was in Charmcaster's body. Gwen procures her spellbook during this period, and keeps the item as a souvenir, eventually learning to use it.

Charmcaster makes a small cameo at the end of "Don't Drink the Water", where she is seen taunting her uncle (who has been reduced to an infant by the Fountain of Youth) and saying that she's giving the orders now.

She appears in "Ben 10 vs. The Negative 10" as part of the Negative 10. Unlike her partners, however, Charmcaster is mainly focused on defeating Gwen (as opposed to Ben).

Clancy

Clancy (voiced by Nicholas Guest), featured in the episode "Side Effects", is a blue-skinned man who has the ability to control any type of insect; the source of this ability is never explained, though since he explains that he had grown up in his grandfather's house along with his insect friends, he is likely a mutant. His eyes glow when he uses his power. Clancy always speaks using first-person plural pronouns like "we", as he speaks for all of his insects as well as himself.

Clancy originally lives at 8610 Chester Street, an abandoned apartment building. When Councilwoman Liang tries to redevelop the area and have his home torn down, he kidnaps her with the intention of feeding her to his insects. Fourarms stops him, but accidentally destroys his home in the process when Clancy's insects swarm him. After that plan fails, Clancy tries to cause the nearby nuclear power plant to meltdown, killing everyone and everything in the city. Clancy makes himself a protective suit out of cockroaches (which are highly resistant to nuclear radiation) in order to survive the blast. A sick Heatblast, whose powers are reversed by the virus, giving him the ability to control cold instead of heat, stops this plan. Finally, he attempts to take revenge on the trio. Once again, he is stopped, this time by Max's San Ju Yen Pien cold medicine, which attracts the bugs and overrides Clancy's control over them, at which point Max easily knocks him out. Clancy doesn't appear to actually be deranged at first, just trying to save his home (although his comment about having his bugs eat the mayor seems a bit overboard), but starts doing things that show him to be sociopathic once it's destroyed along with many of his bugs.

In "Ben 10 vs. The Negative 10," he joins the Negative 10 and is now mutated into a giant bug-like state. Since he bears some resemblance to Stinkfly, the change might have been effected with Dr. Animo's assistance. In that form he demonstrates no longer the capability of human speech.

Clancy then makes a minor appearance in Ben 10: Protector of Earth as a mini-boss working for Dr. Animo.

Joey/Rojo

Joey (voiced by Jennifer Hale) is the leader of a heavily armed female biker gang. When she tries to rob an armored truck, she is thwarted by Ben as Fourarms and two of Vilgax's drones coming after Ben. The remnants of one of Vilgax's defeated drones fuses with Joey as she invesitgates it, and she becomes Rojo (Spanish for red), a powerful cyborg. The upgrade gives her the ability to fly, super-strength, metallic claws, and a pair of blasters attached to each shoulder. Vilgax is able to communicate with her through the parts and force her to track down the Omnitrix for him. Joey is turned back to normal when Upgrade shorts out the spare parts, after which Gwen knocks her unconscious for attempting a sneak attack on Upgrade.

Joey is greedy, wild and amoral, and not hesitant to attack innocent bystanders just because they annoy her. Neither her real name or her cyborg name is mentioned in the show, but are listed as such in the credits.

Joey first appears in the episode "The Alliance". She returns in "Ben 10 vs. The Negative 10" as part of the Negative 10, with alien tech and armor presumably supplied by the Forever Knights. In that episode she has a feud with Charmcaster about being the 'baddest girl' in the group.

Circus Freak Trio

This trio of thieves are recurring minor villains. They worked together in the guise of being freak show performers in Zombozo's circus. As his minions, they would perform to lure in an audience for Zombozo. While Zombozo would feed on the crowd, they would go out and strip the town of all its valuables. After Zombozo was beaten by Ben, they set out on their own. In "Ben 10 vs. The Negative 10", they are all working for the Negative 10 and Sublimino is now their new leader.

Acid Breath

Acid Breath is one of Zombozo's three minions, and without a higher rank to command them, he acts as the trio's leader (with somewhat inconclusive results). His appearance is quite like that of a zombie. He has the ability to project corrosive acid from his mouth in the form of either a vapor (hence the name "Acid Breath") or a liquid, a trick he implies was taught to him by his mother. This acid can easily dissolve whatever he wants it to, even metal and stone.

Despite the potency of his breath, he is one of Ben's least dangerous foes. If his mouth is jammed by an object (such as a baseball), or if something causes him to cough and gag (such as when Gwen blew a fire extinguisher's contents into his mouth), Acid Breath will be briefly unable to use his powers and will be vulnerable to attack. Dee Bradley Baker voices Acid Breath.

Frightwig

Frightwig has pale skin, a tight-fitting body suit, and five orange tentacles for hair. The tentacles are extremely powerful, giving her strength equal to that of Thumbskull. They are also tipped with metal orbs for greater concussive damage. She's also extremely nimble and skilled in acrobatics. However, she, like Acid Breath, is always easily subdued by Ben, usually by getting tied up by her own hair. Cree Summer voices Frightwig.

Thumbskull

Thumbskull, as the name suggests, has a head shaped like a thumb (complete with a fingernail-like hairstyle on his forehead). He also has incredible strength (though inferior to that of Fourarms), but limited intelligence. Like his co-workers, Thumbskull is always beaten very quickly by Ben, even worse than the other two. His name is a play on the insult "numbskull", as well as the obvious appearance gag. Jeff Doucette voices Thumbskull.

Sublimino

Sublimino (voiced by Richard Steven Horvitz) is an evil hypnotist who uses hypnosis to force people to commit crimes for him. Ben ended up as one of his victims, and Ben's aliens forms prove instrumental in retrieving the necessary parts to build a giant hypnosis machine, allowing Sublimino to control an entire mall full of people. When Sublimino hypnotized everyone in the mall, Ben alone escaped the trance. As Wildvine, he brought down Sublimino and broke his hypnotic spell. Other than his hypnotic powers, Sublimino is a weakling, relying on his slaves to protect him using various objects in the mall, and proved no match for Wildvine.

Sublimino first appears in "Midnight Madness." He resurfaces in "Ben 10 vs. The Negative 10" when the Forever King recruits him. He also is the new leader of the Circus Freak Trio.

The Forever Knights

The Forever Knights (likely an evil parody of the Knights Templar), also known as The Organization, is a secret society dedicated to collecting alien technology for their own benefit. Any aliens they capture along the way are dissected and studied; any humans caught with them (like Howell) are immediately deemed worthless and disposed of. Their entire organization dresses as if they were knights, complete with the appropriate, albeit heavily enhanced, weaponry and stylized metal facemasks. They use a coat of arms over a pair of crossbones as their symbols. Enoch (voiced by Richard Doyle) has significant influence in the organization, appearing as their leader in their first three appearances. In their fourth appearance in "Perfect Day", a larger man in a full-body suit of armor called the Forever King is shown to be his superior.

The Forever Knights first appear in the episode "A Small Problem", then known only as The Organization. They attempt to dissect Grey Matter, but are thwarted. Their base is also destroyed, along with the advanced technology stored on the site. At the end of "A Small Problem", Enoch orders his subordinates to find out about Ben, Gwen, and Max.

They returned again in "Ultimate Weapon", in which their formal name is used. In the episode, Enoch attempts to retrieve the Sword of Ekchuah (a sword of incredible power), only for it to crumble to dust when he finally finds it in a temple (according to Max, "That's what happens when your 'ultimate weapon' is over 5,000 years old."). He remains in the temple as it collapses, trying to collect the dust of the weapon.

At the end of "The Unnaturals", Enoch resurfaces as part of an effort to replace the President with a robotic duplicate using a team of robotic baseball players fittingly called the "Squires". His plot was foiled by the Tennysons, though they remain unaware that he was part of it.

In "Perfect Day" they returned, attempting to steal the Omnitrix while trapping Ben in a dream world, using some sort of dream-inducing device. They were foiled when Ben took control of the dream and escaped. Enoch was trapped in the dream world by the end of the episode where Max mentions that he'll remain there until the police arrive. With Enoch's multiple failures, the Forever King decide to leave him be and deal with the Tennysons himself.

The rest of the Forever Knights return in "Ben 10 vs. The Negative 10" to help their leader obtain the Sub-Energy, the world's strongest energy source.

The Forever Knights appear in Ben 10: Protector of Earth, but are shown not to be villains when you complete the South West, later in the game. They manage to discover Vilgax's plan and attempt to use the Cannonbolt DNA extracted from the Omnitrix, combined with a giant robot, to take down Vilgax before it's too late. However, Ben, mistaking Enoch for the main villain, destroys his mech and makes him unable to stop Vilgax.

The Forever King

The Forever King (voiced by Richard Doyle) is the leader of the Forever Knights and the Negative 10, as well as the fourth season's main antagonist. He was originally known as Driscoll and was formerly a Plumber, back when Max was a rookie member. However, he was thrown out of the Plumbers in disgrace when he was revealed to have been stealing alien technology for his own benefit. He later joined the Forever Knights and works his way up the ranks, eventually becoming their leader.

He first appeared in "Perfect Day" where he finds Enoch defeated by Ben. He then leaves Enoch after his multiple failures and decides to take care of Ben himself. He appears again in "Ben 10 vs. The Negative 10" where he rounds up a collection of Ben's old enemies to form a specialized team, in an effort to steal the Sub-Energy, a powerful energy source given to the Plumbers after capturing an alien convict. He eventually manages to steal it and enhances his armor suit with it. But the energy source was eaten by Upchuck and destroyed his suit. However, Driscoll survived and escaped.

Forever Knight Ninja

The Forever Knight Ninja is a member of the Forever Knights and a member of the Negative 10. He first appears in "Ben 10 vs. The Negative 10" and does not have a voice actor (being completely mute).he is killed by up chuck

Other recurring villains

Hex

Hex (voiced by Khary Payton) is a "Master Magician" who is more Gwen's enemy than Ben's. In "Lucky Girl", he possesses five magical charms called the Charms of Bezel that give him the powers of levitation, fire, reincarnation, lightning, and luck, in addition to his own spellcasting abilities. He attempts to steal an ancient spellbook known as the Archamada Book of Spells during the episode. It dates back to the 16th century and contains powerful spells that, when wielded by someone holding the Charms of Bezel, give the wielder unimaginable powers. He is eventually defeated by Gwen, Ben, and Max. Gwen also smashes the charms. Technically speaking, he is Gwen's "Vilgax".

Hex returns in "Tough Luck", where he's searching for the Keystone of Bezel. With it, he can recreate the other five charms and multiply his power ten times. He is accompanied by his niece, Charmcaster, who is his apprentice that freed him from prison earlier in the episode. She eventually betrays him an attempt to get the power of the stones for herself. As Wildvine, Ben crushes the five charms and damages the Keystone, causing it to drain both Charmcaster's and Hex's powers. The Keystone was not destroyed, however.

Hex returns in "Don't Drink the Water", having aged into an old man since his last appearance. Learning of the Fountain of Youth, he tracks it down and uses it to live forever, only to have the fountain vaporized by a child version of Heatblast. As a result, Hex is overexposed and is reverted into a toddler, where he is later found, captured and taunted at by Charmcaster.

Hex (who is revealed to have been possessed by Ghostfreak once defeated) appears in Ben 10: Protector of Earth, but only as a mini-boss that Ben faces at the end of Effigy Mounds.

Sixsix

Sixsix is one of three alien bounty hunters sent to take the Omnitrix from Ben. He has purple armor and strange, clamp-like feet. He is equipped with a jetpack, and his armour is covered with pouches that hold various weapons and projectiles, such as twin blasters, laser discs, a buzz saw, laser blade and whip, a sonic weapon, throwing pikes, grenades, bolas, rockets, and several tentacle-mounted lasers coming out of his back pack. He also has several very strange small claws and hands that extend from his shoulders that are usually used to throw the small pikes coming out of his jet pack, or bombs when he is using his blasters.

Unlike the other hunters, Sixsix only speaks in his own language. The hunters can still understand him, though. Sixsix appears in the episode "Hunted". Sixsix later appears in "The Galactic Enforcers", teaming up with Volcanus as part of his plan to combine Element X with bisynthium alloy (an unspecified form of iron ore) to create an explosive capable of wiping out an entire solar system.

Sixsix and Volcanus reappear in "Perfect Day" as villians in Ben's dream. Later Sixsix appears aagain in the episode(without Volcanus) working with Enoch and Kevin 11 trying to keep Ben from waking up.

He appears as Vilgax's henchman in Ben 10: Secret of the Omnitrix after Vilgax found him drifting outside Incarcecon. His helmet is broken, revealing a gray-skinned creature beneath. Strangely, he seems to become more feral after this happens: Vilgax attaches a leash to him in order to keep him under control. He seems to have developed a grudge against Tetrax since "Hunted", attacking him relentlessly upon meeting him again. He was finally defeated by Tetrax as he tries to escape after Ben defeats Vilgax and his army.

Sixsix appears again in Ben 10: Protector of Earth as a mini-boss, fought at the end of Cape Canaveral. His role is only to stall for time as Vilgax prepares the final phase of his plan. Tom Kenny voices Sixsix.

Volcanus

Volcanus is a Detrovite (the same species as Technorg) who partners up with Sixsix in order to build a weapon capable of destroying a solar system. Unlike Technorg, he isn't enhanced in any way. He is stopped by Ben and the Galactic Enforcers.

Volcanus appears in the episode "The Galactic Enforcers". He reappears in Ben's dream world in "Perfect Day" working alongside Sixsix again. Volcanus recently appeared in "Ken 10", where he was defeated by Ben 10,000 and transported to the Null Void dimension.

Volcanus and Technorg's species appear in "Ben 10 Protector of Earth" as enemies.

John DiMaggio voices Volcanus.

Secondary villains

Bermuda Triangle Aliens

Within the Bermuda Triangle are a vast number of squid-like robotic creatures of varying size (ranging from 3 metres to 12 metres). They bring down ships and planes for an unknown reason, although a reference to them keeping all the craft in an underwater "parking garage" implies that they collect the craft, and have been doing so for quite some time judging by the age of some of the vehicles present. After Donovan Grand Smith took their energy orb, these aliens attempted to retrieve it. Many of them were wiped out when his grandson Edwin rigged the energy orb to implode, destroying the hotel and everything in it. Whether or not the aliens survived is unknown. These aliens appeared in the episode "They Lurk Below".

Eon

Eon is the main antagonist of Ben 10: Race Against Time, played by Christien Anholt. He is the first alien the Plumbers ever caught, having come to Earth nearly two centuries earlier. He seeks to use a device called the Hands of Armageddon to open a temporal rift to his home dimension, bringing forth an invasion force that can conquer the planet. Christien Anholt, in a behind-the-scenes video hosted on Cartoon Network's video service, says that parts of the character are inspired by Darth Vader, whom Anholt is a fan of. An example of this is when Eon kills one of his underlings for failing him, something Vader has also done. Eon's name comes from Eon, a measurement of time.

To complete his plan, Eon requires Ben, who has the Omnitrix. As he explains, the Omnitrix times out to prevent the alien DNA from overtaking the person using the Omnitrix, and by disabling that failsafe he can allow his DNA to overtake Ben, effectively being reborn. Eon does this because he has grown too old and weak to activate the Hands himself. Once he does so, he retreats, because two Eons can't inhabit the same time and place. Ben, having been overwhelmed by Eon's DNA, then attempts to activate the Hands, but is stopped by Max. Through Gwen's pleas, Ben is able to overcome Eon's DNA and return to normal, while Max disables the Hands. The original Eon then attacks Ben, but is defeated when Ben becomes Wildmutt and knocks Eon into the Hands, causing both to disappear in an explosion of energy. What became of Eon is unknown, but it is possible he was killed.

Eon possesses vast time-manipulation powers. He can stop time relative to himself or others, age objects rapidly through directed energy blasts, and throw people with great force by rewinding time and releasing it suddenly. He also says he can travel through time but doing so badly weakens his body. He is the most powerful and calculative villain. He is also able to disrupt the Omnitrix, which now contains his DNA. Eon's appearance is very similar to that of a normal human. His world was lost in another dimension.

Exoskull

A rhino-like cyborg, enhanced by Dr. Animo in the future. In "Ben 10,000" he attacked the present-day Ben when he was first brought to the future, only to be swiftly defeated by Ben 10,000 as XLR8. He seemed to have met Ben's future self beforehand, as he said "Long time, no see" to Ben, and talked about his "revenge".

Voiced by Richard McGonagle.

Fungal Brain/Mycelium

The Fungal Brain is the head of a fungus colony which took control of Camp Opinicon in the episode "Camp Fear". The scientific name for such a structure in real fungi is called a mycelium; incidentally, the Fungal Brain prefers to be called by that term. It has many mushroom-like minions who go and attack various campers. Its plan was to take control of the entire planet by spreading its spores into the atmosphere. It was killed when Ben threw a can of antifungal powder into his mouth, poisoning it and killing all its minions in the process. The Fungal Brain is voiced by Fred Tatasciore.

The Great One

The Great One is a giant, tick-like alien that travels from world to world, sucking the energy from the planets it lands on to feed itself. This process poisons and eventually makes the worlds it visits implode, it is responsible for countless alien species being wiped out. Its shell is nearly impenetrable and its feeding process brings the ground to life as an extra defense, making it very difficult to attack. On top of that, it is followed by a group of worshipers that want to make sure that it completes its task. The Great One is destroyed from the inside by Ben as Cannonbolt. The Great One is responsible for the complete destruction of Cannonbolt's home planet about a week before it tried to destroy Earth, a somewhat ironic accomplishment considering its death at the hands of a member of the same species (albeit a spliced version). The Great One and the worshipers all appear in the episode "The Big Tick". This is quite similar to Galactus and the Silver Surfer from the Fantastic Four.

The Great One's Worshipers

The worshipers are three aliens that accompanied the Great One. (In fact, their respective planets were all destroyed by the Great One, and they decided to follow the doctrine "If you can't beat it, join it".) All three ride on hovering platforms and protect the Great One while it performs its task. Each of them also bears a headdress which seems to integrate a neural interface control device for the hover platforms, a laser beam and a holographic projector.

• The first is a tall alien with grey skin and six tentacle legs. With his composed personality and appearance, he can be considered the leader of the trio.
• The second is a medium-sized and heavily-built alien with four eyes, two tubes protuding from his back, and a large battle axe which can fire laser blasts when swung. He is the most crude and aggressive of the trio.
• The third is a short six-armed alien. He can communicate with the Great One through direct touch, though its interpretation of the Great One's will is dubious at best.

After the Great One's destruction, they show their flimsy loyalty by worshiping Cannonbolt, who had destroyed the Great One not minutes before. They decide to depart when Cannonbolt reverts to Ben, considering a mere human unworthy of their devotion (though the six-armed one had developed a liking to him). They appear in the episode "The Big Tick". The three alien worshipers are voiced by Fred Tatasciore, Dee Bradley Baker, and Paul Eiding.

Jonah Melville

Jonah Melville is a hunter of rare animals, more commonly known as a poacher. He takes the animals he captures and sells them to the highest bidder. He often uses the cover of an animal-rights activist in order to disguise his activities. Jonah Melville appears in the episode "The Krakken", where he tries to steal the Krakken's eggs. He is defeated by Ripjaws and the Krakken and arrested (although the Krakken tried to eat him, but was stopped by Ripjaws).

Jonah's name is a combination of two names that are associated with large water creatures: Jonah, the Biblical figure that was swallowed by a large fish (which Melville nearly was by the Krakken), and Herman Melville, one-time sailor and later writer of Moby-Dick, a story of a sea captain's obsession with a huge white sperm whale. Robin Atkin Downes voices Jonah Melville.

Kane North

Kane North is the twin brother of Abel North (AKA Kangaroo Commando). In the episode Super Alien Hero Buddy Adventures, Kane holds a grudge against Abel because he made Kangaroo Commando's gadgets and Abel took all the credit. When Kane tried to escape, Ben as Wildvine fought him until the Omnitrix timed out. When Kane was about to strike Ben, Abel sneaks behind him and knocks him out. Kane and his brother are a reference to the Biblical tale of Cain and Abel. Just like Abel, Kane is voiced by John Cygan.

Kenko the Shapeshifter

Kenko appeared as the villain of the Sumo Slammer Smackdown video game in "Game Over". He is a shapeshifter and archenemy of Ishiyama, the hero of the game. He overhears Ben talking about the Upgrade token; believing it could be used to allow him to take over the real world, he attempts to obtain it. While Ben searches for the token, he fights and defeats Ishiyama, then assumes his form after Ben reaches the Upgrade token first. He tries to trick Ben into taking him to the real world, but Max's timely intervention in the game as his own player reveals his ruse. As Upgrade, Ben's control over the game allows him to depower Kenko, revealing him to actually be a small, weak, gnomish creature. Afterwards, Kenko is defeated when he is hit by a piece of his own armor after it falls apart. Clancy Brown voices Kenko.

Kraab

Kraab is one of three alien bounty hunters sent to take the Omnitrix from Ben. He has gold-colored armor, a sideways mouth, four scythe-like legs, a samurai sword and a large, powerful pincer on his left hand. Within the pincer is a power blaster combined with a chemical sprayer. He can also use his legs to burrow under the ground and travel quickly from place to place.

Kraab is an experienced bounty hunter and is smart enough to know of a chemical spray that takes away Ghostfreak's power to become intangible. It should also be noted that Kraab talks like an actual hunter, calling Ben his "prey", and saying that he is "hardly worth the hunt". However, Kraab is more robotic than organic, meaning Ben, as Grey Matter, can easily deactivate him. It is possible that when Tetrax knocked the water tower and shortcircuted Kraab. Kraab then comments that he "hates this planet". Kraab appears in the episode "Hunted" and is the only one of the hunters who has not made another appearance since then. Billy West voices Kraab.

Limax

The Limax are shape-shifting slime aliens from an unknown world. The Limax thrive in conditions of fire and heat, hence why they chose to begin their invasion plans in a retirement community situated in the middle of a desert in the summer months. They come to Earth to collect elderly people and devour them; they indicate that young people don't taste as good. The Limax seem to have a hive mind, being able to coordinate throughout a large area without any direct contact, though they do speak to each other. The Limax can merge with each other to form one gigantic Limax. They melt when exposed to cold water, which evidently is poisonous to them. After their plan to kidnap Aunt Vera's retirement community failed, most of them escaped on their spaceship. A few, however, were left behind.

These aliens appear in the episode "Permanent Retirement" and are mentioned in the episode "Perfect Day" when Enoch in the form of Lt. Steel claims that the real Gwen and Grandpa Max are Limaxes in disguise.

Dee Bradley Baker voices the Limax.

Megawhatts

Megawhatts (a play on megawatt) are mischievous little creatures composed of electrical energy who have the physical form of anthropomorphized batteries. They are black and yellow with plus and minus symbols on their back, similar to a battery, and a lightning bolt on their chest. The top of their heads constantly emit electricity. They stand roughly a foot high, have pointy legs (though they usually fly), and have only three fingers on each hand. Their language consists of a series of high-pitched squeaking and chirping noises, though they are apparently capable of understanding English.

Megawhatts can control electricity and can inhabit electrical devices, controlling them from the inside. Being made from electrical energy, they are weak against things that ground it (water being a chief example). They grow stronger by absorbing electricity and can multiply if split in half or given enough power. It should be noted that that when the first one divided, both it and its clone seemed to be surprised, as if they didn't know they were capable of doing it. It should also be noted that Megawhatts are surprisingly strong for their size, as just one was able to lift Grandpa Max, who is many times its size, into the air by his underwear and giving him a flying wedgie. Another notable ability of theirs is that the noises they normally use to communicate can, at a certain pitch and volume, shatter glass.

Megawhatts exist to have "fun", which in their case is to cause trouble wherever they go. While they cause a lot of damage, Megawhatts do not seem to technically be evil, and in fact are not openly hostile to humans, merely lacking any self-control or sense of the harm they may be causing. They only openly attack after Ben tries to attack them, and don't retaliate against anyone but him.

They are said to be either lightning come to life, static cling run amuck, or an alien (the first two were said by the town leader and the last by Gwen). The latter of the three would seem to be correct, given Ben 10,000's use of a Megawhatt as a form on the Omnitrix. Ben's son, Ken, also gets Buzzshock as a beginning alien, except that Ben and Ken can speak while in this form, as Ben can with Benmummy when the original seemed to be mute. However, as the Omnitrix can absorb and integrate DNA for use by the wearer, they could still have originated on Earth.

They appeared in the episode "Tourist Trap", originally trapped in the world's biggest rubber-band ball. Ben's use of the Omnitrix accidentally empowers them enough to escape their rubber prison. They are currently imprisoned within the world's largest lightbulb, which was originally the world's largest fishbowl adapted into a makeshift prison. The mayor of Sparksville has it converted into a lightbulb to replace the lost attraction.

Mr. Beck

Mr. Beck is a mob boss that wanted Gatorboy and Porcupine to win the prize money by threatening to kill their mom, and almost did, until he was defeated by a four-way Ditto tag team. Mr. Beck appears in the Ben 10 episode "Ready to Rumble".

Voiced by Jim Ward.

Phil

During Max's time with the Plumbers, Phil (voiced by Robert Patrick) was his partner. Together, the two managed to prevent Vilgax from stealing nuclear missiles, resulting in the destruction of Vilgax's ship. After that point, the work dried up and the Plumbers were disbanded. Though Max retired, Phil continued the work, capturing aliens and charging various people for the captures.

During an incident with a small but powerful alien, he met up with Max again, and tried to get him to reform the Plumbers. After Max refused, he ended up calling for help to deal with some loose Vulpimancers (Wildmutts). He discovers that Ben has the Omnitrix during this second fight, and pushes even harder to reform the Plumbers. Through his constant insistence and his familiarity with the aliens they'd been fighting, Max discovers that Phil had been abusing the Null Void Projector — a weapon capable of opening a portal to an alternate dimension, which was used as an alien prison — to con people into paying him to remove the aliens. After Max discovers his secret, Phil tries to get rid of him, but he is stopped by Ben as XLR8 and Grey Matter, and in the end Phil ends up trapped in the Null Void himself. When Gwen asks what would happen to him, Max replies, "There are some things about this job we're better off not knowing". Phil is briefly mentioned by Ben in "The Visitor".

Pinky and Missy

When Gwen was in prison in Charmcaster's body, she met two women criminals. Pinky was the overall leader and Missy was her lackey. When Gwen escapes, Pinky and Missy decide to continue their life of crime instead of reforming, so Gwen betrays them by making a pair of clay animals hold them until the police capture them. At the end, the real Charmcaster goes to the same prison, leaving Pinky and Missy to attack her for 'abandoning' them. They appear in "A Change of Face"; Pinky is voiced by Kim Mai Guest and Missy is voiced by Jennifer Malenke.

Road Crew

The Road Crew are a group of road pirates who pillage cars. Their members are known as Baron Highway (a portly man), Turbine (an attractive woman), and Road Rage (a grizzled, uncleanly older man). Baron Highway drives a blue monster truck, Road Rage uses a damaged old light brown tow truck, and Turbine sports a nice red car. In the episode"Ben 4 Good Buddy" the three successfully stole and modified the Rust Bucket in their plans to blow up the new highway, but were ultimately defeated by the Tennysons.

Baron Highway is voiced by John DiMaggio, Turbine is voiced by Jennifer Hale, and Road Rage is voiced by Dave Wittenberg.

S.A.M.

S.A.M. is a robot designed to help the local TV weatherman, Vance Vetteroy, with his broadcasts. His name stands for Sounding Autonic Meterograph. Vance attempts to redesign S.A.M. in the hopes of giving it control over the weather, not just report it. During the test run, S.A.M. is struck by lightning and develops a somewhat HAL-like personality, albeit with more emotion. For some reason, S.A.M. decides to use his new abilities to wreak havoc (why is never explained, though such events would certainly be newsworthy). Ben is able to take S.A.M. offline with help from Grandpa Max and Gwen by using a sound frequency at the end opposite of the spectrum from the hum S.A.M. gives off. S.A.M. appears in "Monster Weather" and is voiced by Jim Ward.

Slix Vigma

Slix Vigma is the coordinator for intergalactic-viewed gladiator games run on a massive stadium ship known as the Megacruiser. Slix himself is a sentient robot that acts as the control center for the entire ship, or at least did until Kevin 11 killed him. just to kill ben himslef Armin Shimerman voices Slix Vigma.

Sludges

The Sludges appear in the episode "My Big Fat Alien Wedding". They are giant, mud-based creatures that can shapeshift into humanoid forms. Their natural state is a legless, vaguely humanoid blob. Females of the species have antennae in this form. They can stretch their limbs and create makeshift weapons from their composite mud, similar to the villainess Inque from Batman Beyond. Being made of a mud-like substance, however, makes them vulnerable to fire and especially water.

The Sludges and the Plumbers have been at war with each other for years. However, the possible wedding between a Plumber, Joel, and one of their own, Camille, leads a group of Sludges to destroy the proceedings. The first two are Camille's parents (voiced by Steven Blum and Grey DeLisle), and serve as the masterminds behind the assault. The third is Camille's ex-boyfriend (voiced by Dee Bradley Baker), whom her parents set up as an initial scapegoat to avoid suspicion only to dissolve in an indoor pool in his fight against Diamondhead. The fourth is an unidentified Sludge that poses as the Best Man. As Heat Blast, Ben hardened up Camille's parents while Max, Gwen, Joel, and Camille defeated the first man.

Zombozo

Zombozo is a vampire-like clown that feeds on the happiness of others. Dressed in appropriate attire, he stages shows to bring people in and then uses a machine he calls the "Psyclown" to drain the happiness and life energy from them, leaving them depleted and sad. In his show, he gave his secret away on purpose many times, just to get more strength. In the most extreme cases, it even seems to age people as it did with Gwen Tennyson. During all this, his minions strip the town of all its valuables. He was eventually defeated when Ben overcame his fear of clowns and terrorized Zombozo as Ghostfreak by peeling back his skin, causing him to explode in a burst of confetti. Whether he died or not remains unknown.

While Zombozo's henchmen reappeared in a future episode, he himself did not. The three indicate that they have not seen the clown since his defeat. His name is a portmanteau of both "Zombie" and "Bozo". He bears some resemblance to The Joker from Batman. When Zombozo appeared in the episode "Last Laugh", he was voiced by John Kassir.

See also

• List of characters in Ben 10