Ben 10: Alien Universe

Ben 10: Alien Universe was a short-lived Ben 10 fan-fiction series that ran alongside Ben 10: Alien Force. It first aired December 11, 2008, and was meant to be followed by sequel series Ben 10: Unleashed. The show's sequel never continued further than the pilot, but a spin-off fan-fiction telling the story of between Ultimate Alien and Omniverse will be releasing sometime in 2012.

Plot
The show had several villains throughout the story, a few of which appeared as main villains. In the first season (the only completed season), the show introduced a first episode much akin to the first episode of Ben 10: Alien Force, where Ben retrieves the Omnitrix to fight a DNAlien who attacks him during a boxing training session. In the first episode, Ben and Gwen meet Kevin for the first time in 5 years and Ben fights him solely using Swampfire. The gang drive off telling each other's stories of the past few years, when Kevin's car breaks down and the gang are forced to exit the car. Kevin is abducted, and Gwen and Ben as Jetray chase after him only to find him beating up so DNAliens. At this point, Kevin joins the gang as a member.

Throughout the season, Ben, Gwen, Kevin, and at one point, even Grandpa Max, face off with DNAliens, Highbreed, Albedo, and even Hex. In this series, Albedo is at one point reverted to his Galvan form, but later revealed to have been changed back to his Human/Ben self with unlimited access to all alien DNA and their transformations. Albedo is the first villain met in the series, other than the DNAliens who appeared in the first episode, and he faces off with Ben in the second episode. At the end of the battle, Albedo's omnitrix powers out and malfunctions, leading to Ben eventually using Alien X's abilities to revert Albedo to a Galvan, and send him back to his homeworld. In episode 3, a parody of "Gwen 10" is seen where the first episode plays out as if Gwen had gotten the watch first in that episode and Ben remembered the events of the last two episodes. Nonetheless, in the end, a blue mutated Cerebrocrustacean (Brainstorm's species) pinches the Omnitrix, removing it from Gwen's hold and returning it to Ben at last. Later, in episode 4, DNAliens are met again when the gang meet Alan Albright akin to the third episode of Ben 10: Alien Force. In Episode 5 "Homesick Trilogy: Part 1," Ben is hurt by a Gwen who is revealed to be a DNAlien angered at the fact that his leaders were stopped and his purpose was no longer thanks to the fact that the Highbreed didn't need them anymore for their missions. In episode 6 "Feel My Ghostly Wrath," Ben faces off with Ghostfreak whom he believes is the cause of the loss of Gwen and the return of the DNAliens. There, Ben meets a Plumber who goes crazy and nearly kills Ben. In the last part of the Homesick Trilogy, titled "The Final Part," Ben and Kevin apprehend the most likely DNAlien group to have Gwen, where they find Gwen, and Ben uses Way Big to beat down the Highbreed behind all of it. In "Alien Queen," a meant-to-be four-part story, Alien Swarm is parodied. In Episode 10 "Artificial Consequence," the gang meets up with Darkstar for the first time and faces off when Kevin is transformed into a giant hulking monster when he and Darkstar attempt to revert him to hsi proper human form. In Episode 12 "Darkstar's Inside," Darkstar is seen again ripping aliens out of the watch using Azmuth as a hostage who's known to have the passwords and lockout keys to get inside. In Episode 14, the second episode of the second season, Darkstar is seen one last time in "Darkstar Falling," where his villainship is cancelled for the show thanks to Ben. In Episode 15, Clancy returns. In episode 16, the last known episode of the series, "Charmed to Perfection," Charmcaster returns and uses some spells to use Ben's aliens to defeat him. She is stopped by Ben, Gwen, and Kevin.