Ben 10: Ultimate Alien
#1 - Solitary Alignment 8.74
Season 2 - Episode 23
Azmuth reveals how Old George got his sword and slayed Diagon.
#2 - Escape From Aggregor 8.73
Season 1 - Episode 5
In the Himalayas, Dr. Animo and his mind-controlled Yeti were fighting with Ben. Ben, as Brainstorm, mind-controls the Yeti and frees him. Kevin and Gwen deactivates the Devalution bomb. Gwen calls the Plumbers to take them, the Plumbers informed them that there is an alien action in Bellwood. Ben encounters the turtle-like alien Galapagus, who was on a rampage to find Ben. He escaped from Aggregor and tells Ben how he ended up captured alongside four other aliens in a plot to permanently absorb their powers. Galapagus ended up telling Ben how he, Bivalvan, Andreas, Ra'ad, and P'andor escaped from Aggregor when Magister Prior Ghilhil answered the distress call and did an inspection which ended with Magister Prior Ghilhil getting knocked out by Aggregor. Though the aliens escaped from Aggregor's spaceship, they crash-landed on Earth. After Ben's Ultimatrix scans Galapagus' DNA, he arranges for the Plumbers to get Galapagus back to his home planet. Unfortunately for Galapagus, Aggregor was posing as a Plumber.
#3 - Ben 10,000 Returns 8.60
Season 2 - Episode 10
Following a visit from Paradox after a fight with Eon, Ben 10,000 arrives 20 years from the future to seek the aid of his past counterpart in tracking down Eon.
#4 - The Enemy of My Frenemy 8.57
Season 2 - Episode 25
Gwenand the gang revisit Legerdomain in hopes of rescuing Charmcaster.
#5 - Catch a Falling Star 8.56
Season 2 - Episode 27
Jennifer Nocturne is recaptured by Captain Nemesis aka Overlord.
#6 - Greetings From Techadon 8.47
Season 2 - Episode 15
Techadon robots go after Ben on orders from Vulkanus
#7 - The Flame Keeper's Circle 8.46
Season 2 - Episode 16
Julie joins a cult that worships Vilgax
#8 - Map of Infinity 8.37
Season 1 - Episode 11
With his new powers, Aggregor easily defeats Ben and his friends. Azmuth tells Ben that Aggregor intends to steal the Map of Infinity, a complete map of the entire universe. With it, he'll be able to find the Forge of Creation, the birthplace of the universe. He further explains that Aggregor stole the five aliens' powers to protect him from the traps guarding the map, which is split into four pieces. In order to keep him from assembling the map, the team tries to take one of the pieces first. Aggregor, however, simply follows them and steals it after they disable the traps for him.
#9 - Moonstruck 8.30
Season 2 - Episode 11
The history of Max and Verdona Tennyson in flashbacks.
#10 - Inspector 13 8.30
Season 2 - Episode 24
A mysterious weapon master from Techadon visits Earth and wants the Ultimatrix.
#11 - The Perfect Girlfriend 8.27
Season 2 - Episode 18
The Perfect Girlfriend
#12 - Video Games 8.23
Season 1 - Episode 4
After defeating Ssserpent with Fourarms, Ben's celebrity status lands him in a starring role in a video game. The developers ask him to show off all his aliens' different moves so they can be implemented into the game. In reality, TV reporter Will Harangue has been using the video game to build a giant spider-like robot that knows all of Ben's aliens' moves from when he openly showed them. After being defeated twice by Harangue's robot, he challenges Ben to a final showdown on live TV. After realizing how Harangue's robot can predict his aliens' moves, Ben uses Humongousaur with sumo slammer moves to fight it. He damages it until it has lost control, but its still shooting randomly. Ben then turns into Nanomech which was the only alien with moves that were not installed into the robot, Ben is able to defeat it from the inside.
#13 - Prisoner #775 is Missing 8.21
Season 2 - Episode 12
The secrets of Area 51 are revealed to Ben Tennyson by Colonel Rosum after Old George infiltrates Area 51. (ChamAilen and Ultimate Wildmutt first appears in this episode).
#14 - It's Not Easy Being Gwen 8.21
Season 2 - Episode 9
Gwen has always been a multi-tasker, trying to juggle school, hobbies, friends and her work as a hero, waking up early and going to sleep late. But Gwen's already packed day is about to get worse when Dr. Animo attacks with an army of giant frogs and Gwen is forced to make a hard choice.
#15 - Couples Retreat 8.18
Season 2 - Episode 26
Charmcaster and Darkstar team up to destroy Ben, Gwen and Kevin.
#16 - Too Hot To Handle 8.17
Season 1 - Episode 6
Eager to escape his containment suit, P'andor (one of the aliens who were captured by Aggregor) offers a huge cash reward to anyone who can break him out of it. Everyone who tries to break the suit ranging from Buzz, Hammer, and Surgeon fails, save for Kevin, who uses a piece of Taednite to pierce it. But, when Kevin's Plumber's badge senses that the contents of P'andor's suit are radioactive, he stops trying to open it. Enraged, P'andor then offers Buzz, Hammer, and Surgeon an even bigger reward if they capture Kevin. Kevin escapes, but he accidentally leaves his piece of Taednite behind. P'andor tries to use it to break his suit open, but only after failing to do so, he realizes that he needs Kevin's help. He sends his hired minions to kidnap Kevin, and then tricks him into using the Taednite to slash his suit open. Freed from his suit, P'andor heads for a power plant to absorb all of the nuclear energy inside. Working together, Ben and Kevin are able to trap P'andor back inside his suit, and deliver him to a pair of Plumbers who offer to take him back to his home world. Unfortunately, Aggregor intercepts the Plumbers' ship in space and recaptures P'andor.
#17 - The Eggman Cometh 8.17
Season 2 - Episode 28
Dr. Animo returns with a plot to transform eggs into pterodactyls.
#18 - Eye of the Beholder 8.17
Season 2 - Episode 2
Ben, Julie and the rest of the heroic crew embark on a dangerous journey that could cost them all their lives in an effort to achieve the safe return of Ship and his former owner Baz-L.
#19 - Revenge of the Swarm 8.12
Season 2 - Episode 6
Victor Validus resurfaces and attacks Ben at night. Elena Validus and the nanochips return.
#20 - Perplexahedron 8.11
Season 1 - Episode 15
With the fourth piece of the Map of Infinity almost in Aggregor's clutches, the gang chase him through the artificial planetoid known as Perplexahedron.
#21 - Duped 8.10
Season 1 - Episode 2
Ben needs to be at more than one place at once; he has to fight the Forever Knights with Kevin, go to Julie's tennis game, and see a Sumo Slammers movie. So Ben transforms into Echo Echo and divides in three and changes back to Ben, but this time there are three Bens with one part of his personality. One is the real Ben, the other is the honest, intimate Ben, and the last one is the immature Ben. The Honest Ben goes with Kevin to the museum, the Immature Ben stays to watch Julie's match, and the real Ben goes to see Sumo Slammers. Urien (a king of a fraction of Forever Knights) is after some strong suit of battle armor. When Honest Ben and Kevin are in danger, Urian is in the battle armor and attack Intimate Ben and Kevin, the real Ben and the immature Ben have to help them stop Urian. All the Bens go Echo Echo and change back into one. Ben later defeats Urian with Lodestar and heads to back to the tennis match, where its revealed that his plan backfired and he is scolded by his friends for his foolish plan which ruins Julie's game (although she won) and causes Julie to angrily storm off. Gwen angrily storms off too, along with Kevin, leaving Ben all alone to repent for what he's done.
#22 - Basic Training 8.06
Season 2 - Episode 8
Ben, Gwen, and Kevin are summoned to a Plumbers' Academy to go under training that is supervised by Magister Hulka.
#23 - The Ultimate Sacrifice 8.05
Season 2 - Episode 19
The ultimate aliens inside Ben's Ultimatrix demand their freedom!
#24 - Fused 8.03
Season 1 - Episode 8
After ambushing Ben at his house, Ra'ad (one of the aliens captured by Aggregor) blames him for letting Aggregor recapture the other four aliens through the Ultimatrix. While trying to resist being scanned by the Ultimatrix with his electric powers, Ra'ad causes it to malfunction, and ends up deactivating it while both his and Ben consciousnesses trapped within his body. Despite Ra'ad's protests, Gwen and Kevin reactivate the Ultimatrix, and separate Ben from the alien. But in doing so, they alert Aggregor to their location. Ra'ad flees, leaving the others to be wiped out by the Osmosian. After Kevin scolds Ra'ad for his cowardice, the alien decides to sacrifice himself to save Ben, and is recaptured by Aggregor in the process. After the battle, Ben swears that he will do whatever it takes to save the captured aliens.
#25 - The Creature From Beyond 8.00
Season 2 - Episode 7
The Forever Knights unleash an evil force mistaken for an ancient weapon.