This is the episode guide for Ben 10: MEGA Alien.
Series Premiere: 2 years have past since the events of Ben 10: Ultimate Alien MEGATRIX; Ben, Gwen and Kevin open up a brand new Plumbers academy in Bellwood when a silhouetted alien snatches Gwen. The alien hides her with power draining bands over her body to prevent her from getting out.
Zs'kayr returns with a vengence. He begins slowly torturing each member of the team until they discover what is happening and manage to stop him!
After Azmuth being reckless while trying to fix the Ultimatrix when the ultimates escaped the Ultimate Forms have returned. This time Ben must deal with the 6 female versions along with Ultimate Wildmutt, Ultimate FuzzBall, Ultimate Hopefull and Ultimate Goop.
As promised, Ben, Gwen and Kevin return to Ledger Domain to help Charmcaster in her battle against Adwaita and to free all magical beings within that planet.
Will Harangue teams up with Psyphon to trick out the Stalker. It begins to send miniature versions around attacking Ben and study his routine. After three weeks it breaks into Ben's house and captures his parents as bait. After defeating the Stalker, Psyphon leaves to personally fight Ben.
After his defeat, Psyphon's new and improved electrical R.E.Ds are activated automatically and begin going after Ben.
Adwaita returns and wants revenge on Ben Tennyson.
The Plumbers Academy from Press Conference returns. Ben, Gwen and Kevin must test it out to make sure everything is in order before it is opened for the public. Soon they find out that someone is rigging the tests... Will they make it out alive?
The Vreedles pay a Weaponmaster of Techadon to create a gun that shoots out a ray to turn people into clones of themselves. They begin scouring the universe creating clones and when Ben turns up to fight them as Eatle he gets hit and is stuck in the form of Eatle with some Vreedle features.
Albedo returns and enters the MEGATRIX II. When he returns he is carrying a small blob of DNA. He throws it and it evolves into Ultimate Way Big. The sentient Ultimate Way Big begins destroying Bellwood. Albedo explains that the DNA was growing when the other Ultimate forms escaped but didn't get a chance to finish growing before Azmuth fixed the glitch so it lived on as a blob of DNA. Now Ben, Gwen and Kevin must stop Ultimate Way Big before Albedo can convince it to work with him.
Ben finally gets his own place, just as he had been wishing for and it was built to function as not only his home but his headquarters too! But on moving day a lot of his old enemies show up.
This episode is from Adwaita's POV. Adwaita goes hunting for Animo to be mutated. When he finds Animo, he agrees to help as long as Adwaita runs some errands for him. Once Adwaita has completed the errands, Animo steals his abilities.
A distress call is sent from Khoros. Ben, Gwen and Kevin are sent to investigate a Tetramand that is shooting ice around. When they arrive, the MEGATRIX II samples the Tetramand's DNA despite the fact that there is already a sample. Isn't there?
The Alpha Nanite manages to break free from its containment pod and reenters Ben's Universe. Ben tries to defeat it but immediately realises he needs the help of another hero and enters Stan Rumin's Universe, followed by the Alpha Nanite who absorbs the power of both trixes and becomes the MEGA Ultra Nanite.
Brian and co. break Rob out from Incarcecon and they go after Ben.