Despite being a minor antagonist in the original show, Zombozo played a key role by introducing the Circus Freak Trio, who later became recurring villains. His episode was also the first one to hint the existence of Ghostfreak's true form, possibly anticipating the Zs'Skayr storyline.
Long before the events of the series, Zombozo was bitten by a zombie and then left for dead. However, he didn't die and was ultimately rescued by a circus, presumably the same one which hosted his shows in his first appearance. However, the damage was already done and Zombozo became a zombie.
In the episode "Last Laugh", Zombozo uses his shows to use his "Psyclown", which robs the unlucky person of their joy and life energy for the clown to eat. While this is happening, his minions rob people in the town. Although not majorly powerful, he posts a mental threat for Ben, due to his coulrophobia. However, Ben manages to steal his nerves after seeing his family in danger, and uses Ghostfreak to make the clown explode. He is not seen again for the remainder of the series.
Ben 10: Ultimate Alien
Zombozo makes his long awaited return in the episode "Hit 'Em Where They Live". After Ben's identity is revealed, Zombozo decides to attack him with several of his other foes, such as Sevenseven, Charmcaster, and Vulkanus. After forming a team with the later two, he uses a captive Sandra as a trap, bringing them to his lair to attack them. He tries to kill Sandra in a torturous way, but this fails as Gwen becomes furious at the site of her pain, transforms into her Anodite form, and yells at the clown to leave both the Tennyson's and Kevin's alone. After this, she lets him live to tell any other villain the same thing.
Ben 10: Omniverse
Making his first appearance in "The More Things Change: Part 1", Zombozo first steals a brain from the "Brain Bank". However, he is stopped by Lodestar, beaten, and is taken away.
Next, he appears in "Special Delivery", where he is seen in Psyphon's auction. Once Psyphon notes the Dwarf Star is missing, he goes with Fistrick and Trumbipulor to find it. However, he is beaten by Armodrillo, and after he teams up with Psyphon to stop Ben, Humungousaur.
He makes a final appearance in the episode "Something Zombozo This Way Comes", where he escapes from Plumber Headquarters by putting a costume of himself over Jerry and putting him in his cell to fool everyone. Bringing back his lackies, he and his goon feeds on people's fear, turning them into zombies. Zombozo regains his power due to Ben's remaining fear, but destroyed the machine after seeing Toepick, who he fears. He then escapes using a cannon.
Ben 10 (2016)
Zombozo returns in the 2016 reboot of Ben 10, with a far larger role. Most of his plans involve hypnotism, such as in "Clown College", where he tries to steal people's money while they are hypnotized, "Zombozo-Land", where he buys Adrena-World to make the "hypno-tower" to hypnotize everyone once more, "Vote Zombozo", where he tries to become mayor of Sleepy Town with hypnotism, and " Welcome to Zombozo-Zone!", where he hypnotized people to believe he was a king and act like they were in the medieval times to earn the favor of the Forever Knight.
He also posed at a driving instructor in "Bomzobo Lives" to try to have Max imprisoned, "Super-Villain Team-Up", where he teams up with Vilgax to try to both take his revenge and help him in the latter's schemes (getting thrown off the ship when he annoys the alien warlord.), "Dreamtime", where he uses a machine to haunt Ben's, Gwen's and Max's dreams, and "Speechless on the Seine", where he swaps the Louve's art for clown-inspired knock-offs.
Cunning, manipulative, sadistic, and cruel, Zombozo is a vile man who enjoys gallows humor, and using Ben's fear for his own gain. In Ben 10: Ultimate Alien, he is more psychopatic, using weapons to torture Sandra to death and possibly burying someone alive, as he mysteriously carries a shovel in one scene.
Zombozo never or rarely attacks alone, always gathering together a crew to do his dirty work for him. Originally, this was his Circus Freak Trio and later Zombozo leads a coalition between Vulkanus, Charmcaster and Sevenseven (and eight others who were all warded off by Max before he was injured fending off Sevenseven).
Powers and Abilities
Often using machines to do his dirty work, Zombozo can also teleport in a puff of smoke or confetti and creating illusions. He also has a set of comedy based weaponry, such as caltrops, acid in a seltzer bottle, streamers made from steel, a extendable arm to grab people, a enhanced joy buzzer, dynamite, and a large hammer. He also has the ability to fly by holding a flying toy airplane.
- Due his appearance and characteristics, it's likely that Zombozo was based on The Joker, Batman's iconic archenemy. However, Zombozo's obsession with fear seems to more closely resemble those of the Scarecrow, another popular member of Batman's rogue gallery.
- Ben acts like he doesn't remember Zombozo to hide his own fear of clowns.
- In Ben 10: Ultimate Alien, Gwen seems to have a grudge against Zombozo, likely due to her almost perishing to his Psyclown. This is a bit odd, however, as due being hypnotized, she may have not be able to remember it, but it's highly possible that Ben or Max told her what she did during her trance.
- While in the original series Zombozo was already an scary and creppy villain, Zombozo arguably is more depraved and evil in Ben 10: Ultimate Alien, as he displayed a much more sadistic and psychopathic behavior, used lethal weapons and tried to make Ben and the Tennyson family suffer by killing Sandra, slowly and scarily. It's even suggested at the beginning of the episode that he has buried someone. Even Charmcaster goes to fear him just like her uncle Hex.
- Among fans, Zombozo became popular as in his first two appearances (which were the most notable), after being defeated, he simply dissapeared without explanation, leading the audience to wonder about whether he had been killed, scared, arrested, etc.