Ben, Gwen, and Grandpa Max attend a family wedding for Max’s nephew Joel and his bride-to-be, Camille. Before the day of the wedding, Ben interrupts a mud alien’s attempt to sabotage the wedding. Ben defeats the sludge alien as Cannonbolt but finds the groom’s parents pointing rifles at him soon after. He escapes with Gwen’s […]

When Ben and Max go on a fishing trip with Captain Shaw, they encounter the Krakken that lives in the lake. With Gwen’s help, they find out that the creature is upset because Jonah Melville, a poacher pretending to be an animal lover, is stealing its eggs.

Ben transforms into Grey Matter to escape from Ghostfreak and Viktor. He is able to discern Ghostfreak’s plan from a computer terminal: using the corrodium to amplify the power source of the orbiting space station, in conjunction with the device the alien werewolf built in New Mexico, Ghostfreak is intent on covering the daylight side […]

During a trip to Yellowstone National Park, Ben discovers the eleventh alien on the Omnitrix, Cannonbolt. At the same time, a meteor crashes nearby unleashing a giant, tick-like alien called the “Great One” that intends to devour Earth. Ben easily defeats the worshippers, but the Great One turns out to be impervious to the original […]

Distracted by Ben and Gwen quarreling, Max almost hits a young camper named Gilbert on the road. They take the boy back to his camp, Camp Opinicon, only to find no one there. As they investigate the premises, they find two more children, twins named Andy and Mandy, who are hiding from something that caused […]

A shuttle launch at NASA is interrupted by a purple lightning storm, which attracts the attention of the Tennysons, who hope to discover the origin of the alien werewolf and mummy. While at NASA, Ben runs into an ill-tempered scientist named Dr. Viktor. Surveillance tapes associate him with the purple lightning storm, and he is […]

Dr. Animo has just escaped from prison with the help of a mutated seagull, plotting to get revenge on Ben, who is at the beach with Gwen and Max. Ben is being impulsive as no one will play with him, until he is confronted by Animo’s seagull. During the fight, Ben discovers a new alien […]

When Ben tries to take apart the Omnitrix to see how it works, he ends up breaking off its face and causing weird combinations of his alien forms when he transforms. Additionally, the broken piece begins mutating the smaller creatures it comes into contact with. Meanwhile, Dr. Animo escapes from prison and, during a battle […]

After damaging Gwen’s new laptop, Ben enters a mutant wrestling competition as Four Arms to earn some money to replace it, becoming an instant celebrity. During the tournament, he fights a pair of mutant brothers who owe a mob boss a large sum of money to save their farm. They entered the competition to pay […]

The family ride a jet belonging to Grandpa Max’s old friend, Donovan GrandSmith, who owns an underwater resort in the Bermuda Triangle. At the entrance, they receive a warm welcome from Donovan himself, though they also meet with his grandson, Eddie, who doesn’t seem to be excited about their guests. When Eddie, Ben, and Gwen […]

As Ben and Gwen are planning Max’s birthday on the shore of Horse Thief Lake, a mysterious stranger appears and kidnaps her, so Ben follows her into a strange portal. When the dust settles, Ben suddenly realizes he is twenty years old in the future, where humans and aliens live peacefully. Ben then learns that […]

While visiting Washington, D.C., Ben confronts Dr. Animo, a disgruntled scientist whose Transmodulator can mutate living animals, and even resurrect dead ones, and eventually learns a lesson about what being a hero really means.

While visiting a travelling circus, Ben fights an evil clown named Zombozo who is draining people’s souls through their laughter. Conquering his own fear of clowns, Ben defeats Zombozo by terrifying him as Ghostfreak, and saves his family. Ben admits that he scares himself while fighting as Ghostfreak.

While in a tourist trap town called Sparksville[disambiguation needed], Ben plays a practical joke that accidentally unleashes Megawatts, small electric creatures. Ben must stop them from multiplying out of control and destroying the town, and turns into Heatblast to seal the Megawatts in a large fishbowl.