List of Ben 10: Ultimate Alien episodes

Ben Tennyson's secret identity is exposed to the world by an online video, ending his secretive life of heroism. Public opinion on Ben is polarized; he is idolized as a superhero by kids and teens, but distrusted by adults, particularly news anchor Will Harangue, who deems Ben a menace. Ben, Gwen, and Kevin decide to pay a visit to the Internet conspiracy theorist who exposed Ben's identity, revealed to be a ten-year-old boy named Jimmy Jones who runs a website on alien sightings. Not recognizing one of the aliens on Jimmy's website, Ben and his team travel to Orlando, Florida, the site where the photograph was taken, to investigate. Ben's team is brought into custody by the U.S. military, where Air Force Colonel Rozum explains that the alien in question has been stealing parts from a NASA interstellar rocket called Orion. Ben confronts the alien, named Bivalvan, who explains that he is trying to leave Earth after having been stranded there. Ben defeats Bivalvan, who reveals that he is from the Andromeda Galaxy and was kidnapped along with four other aliens by a monster named Aggregor. Ben and his team leave to retrieve the Plumbers, but Bivalvan is recaptured by Aggregor. Later, Ben's classmates take his side and clap for him and the lives he's saved.

Ben's girlfriend Julie Yamamoto has a major tennis match, but Ben is torn between attending and aiding Kevin in stopping the Forever Knights from robbing a museum, while also wanting to watch a new Sumo Slammers movie. Ben eventually turns into Echo Echo and divides into three copies, then returns to his human form so that he can attend all three events at once. However, the split causes Ben's personality to be divided among the trio; while the arrogant Ben attends Julie's match, the kind Ben aids Kevin and the rational Ben watches the movie. Eventually, all three Bens reunite to help defeat the Forever Knights to prevent them from stealing ancient alien battle armor. Ben attempts to reconcile with Julie, but after revealing his actions, she is disgusted with him and storms off.

Ben learns from Grandpa Max that the exposure of Ben's identity has caused various old enemies of his to crawl out of the woodwork, seeking revenge by targeting Ben's loved ones. Ben, Gwen, and Kevin trail Ben's father Carl, intercepting a team of villains consisting of Charmcaster, Vulkanus, and Zombozo the clown. The team succeeds in protecting Carl and split up to protect Ben's family, but Gwen is ambushed by Charmcaster, resulting in Ben's mother Sandra being captured. The team tracks Zombozo to a nearby circus, where Kevin defeats Charmcaster and Ben defeats Vulkanus. Gwen is captured by Zombozo, but her fury prompts her to awaken her innermost anodite self (one year since "War of the Worlds, Part 2") and frightens Zombozo into fleeing, rescuing Aunt Sandra in the process.

Ben is approached by video game producer Oliver Thompson, who invites Ben to be the star of his own video game, scanning Ben's alien forms into a computer for motion capture. In reality, however, Oliver is in the employ of Will Harangue, who is developing a battle robot called the Stalker to target and destroy Ben by analyzing and predicting his moves. The Stalker attacks and nearly kills Ben, but Harangue holds back, wishing to exploit Ben's battles with the Stalker for television ratings. He publicly challenges Ben to a final battle at the National Mall in Washington, D.C. Ben is able to defeat the Stalker by using Nanomech, who was too small for the computer to scan; subsequently, Ben uses Way Big to crush the Stalker as well as Harangue's car.

Ben, Gwen, and Kevin defeat an alien rampaging through the streets of Bellwood. Through a universal translator, they learn that the alien, Galapagus, was only trying to get Ben's attention in order to seek his help. Galapagus explains that he was one of the five aliens from the Andromeda Galaxy captured by Aggregor, who brought him into a cell on his spaceship along with the other prisoners: Bivalvan, Ra'ad, P'andor, and Andreas. The aliens manage to escape, but are divided on what action to take: Bivalvan, Ra'ad, and Galapagus send a distress signal out to nearby Plumbers, while P'andor and Andreas confront Aggregor. Aggregor defeats and recaptures them, subsequently killing Magister Prior Gilhil, the Plumber responding to their distress call. Galapagus seemingly betrays the other aliens to Aggregor, but instead turns on Aggregor and helps them flee to a nearby spaceship, which they take to Earth and then go their separate ways. Ben sends Galapagus home via a Plumber ship, but the pilot is revealed to be Aggregor in disguise, who recaptures Galapagus.

Kevin takes on an underground job to open a safe for a large sum of money, only to discover that the employer is P'andor, one of the missing Andromeda aliens, who wishes to be freed from a containment suit that he has been kept in. Kevin refuses to free P'andor after his Plumber's badge detects radiation in the suit; the two battle, but Kevin flees, and P'andor steals a shard of taydenite - the strongest mineral in the galaxy - from him. After Kevin informs Ben and Gwen about P'andor, Gwen insists that they help free him, but Kevin refuses on the basis of him being too dangerous. The trio find and confront P'andor, who attempts to use the taydenite to free himself, but is unsuccessful; he realizes that he needs Kevin to absorb the taydenite in order to free him. P'andor has his minions kidnap Kevin, who taunt him into liberating P'andor, revealing himself as an energy-based alien who absorbs radiation. Ben disguises as Bivalvan and tries to dissuade P'andor from attacking a nuclear power plant, but this only results in a fight. Ben and Kevin ultimately work together to defeat P'andor, who is arrested by the Plumbers. Aggregor then attacks the Plumbers' ship and captures P'andor.

Argit is running a con selling insurance to the Forever Knights, threatening that if they do not pay him, he will destroy their castles. Ben, Gwen, and Kevin investigate and discover that Argit has befriended Andreas, one of the missing Andromeda aliens, and manipulated him into destroying the castles; out of fear, the Forever Knights have now become Argit's servants. Argit is confronted by Sir Dagonet, a legendary Forever Knight seeking to liberate the knights from Argit's influence; he captures Argit, Andreas, Ben, Gwen, and Kevin, intending to execute Andreas using an energy cannon. Ben and the team free Andreas, but Dagonet turns the cannon into a bomb and flees with the knights. On Argit's insistence, Andreas absorbs the bomb's blast, saving the others but seemingly dying in the process. Kevin punches Argit in outrage, and they part ways. Later, Andreas is shown to have survived, and is recaptured by Aggregor.

Ben is attacked in the dead of night by Ra'ad, the last of the Andromeda aliens, but Ben defeats him. Captured in the abandoned military base at Los Soledad, Ra'ad reveals that Aggregor recaptured the other four aliens and blames Ben for it. Ra'ad asserts that the Ultimatrix led Aggregor to the other aliens, and attacks it in an attempt to deactivate it, causing an explosion and vanishing. Ben and his team are subsequently attacked by Aggregor, whom Kevin realizes is an Osmosian - the same species as Kevin's father, and thus possessing the same power to absorb energy that Kevin has. Ben transforms into an Amperi, the species of Ra'ad, and is trapped in his alien form; he realizes that he and Ra'ad are sharing their consciousness. Fleeing from Aggregor to Kevin's garage, Kevin is able to split Ben and Ra'ad, but Ra'ad flees as Aggregor arrives. Aggregor defeats Kevin and Gwen and nearly kills Ben, but Ra'ad intervenes out of guilt and electrocutes Aggregor. Kevin's garage explodes, and Ra'ad is recaptured, but Ben vows to use the powers of the Andromeda aliens to rescue them.

Vampire Summer movie star Jennifer Nocturne is attacked by mercenaries, but rescued in a joint effort by Ben and Carl Nesmith, a.k.a. Captain Nemesis, a real-life superhero and billionaire whom Ben idolizes. Jennifer is infatuated with Ben and kisses him, to Nesmith's jealousy. Subsequently, Ben and Jennifer become friends, much to Julie's jealousy. It is then revealed that Nesmith secretly orchestrated the attack on Jennifer to gain popularity, and is conspiring with Will Harangue to boost his public image. After Ben and Nesmith work together to battle against extradimensional robots, Harangue slanders Ben and prompts Nesmith to challenge Ben to a friendly competition. Ben wins the competition, which outrages Nesmith, who resorts to kidnapping Jennifer and Julie. Ben rescues the two and defeats Nesmith, chastising him for losing sight of what it means to be a hero. Nesmith is then arrested.

A group of Plumbers ambush Aggregor in an attempt to rescue the Andromeda aliens, but are overwhelmingly defeated. The team then learns from Colonel Rozum that Aggregor has taken the aliens to Los Soledad; Professor Paradox then appears and reveals that Aggregor is using Paradox's technology to facilitate the total absorption of the aliens. Ben and his team confront Aggregor, with Kevin attempting to reason with him, insisting that energy absorption causes Osmosians to lose their sanity. Aggregor asserts that these are merely lies, and absorbs the aliens into himself; the aliens disappear, and Aggregor emerges as a monstrous amalgamation of their forms.

Ultimatrix alien debuts: Ultimate Swampfire

Believing that Aggregor has killed the Andromeda aliens, Ben attacks him viciously, only to learn that Aggregor's new form makes him virtually invulnerable. After Aggregor leaves Earth, Ben and his team are brought to Galvan Prime by Azmuth, who explains that Aggregor's goal is to acquire the Map of Infinity - a complete map of spacetime which will lead him to a mysterious realm known as the Forge of Creation, where he can acquire unlimited power. Because of the map's importance, Professor Paradox separated it into four pieces and hid them throughout the universe in secure locations; Aggregor absorbed the powers of the Andromeda aliens to make him powerful enough to retrieve them. Ben, Gwen, and Kevin travel to the tidally locked planet Mykdl'dy to retrieve the first piece of the Map of Infinity, encountering a group of Necrofriggians and entering an ancient temple. Inside of the temple, the trio evade a series of traps, but end up at the mercy of Aggregor, who takes the piece of the Map of Infinity and leaves. Ben and the others barely escape, resolving to prevent Aggregor from getting any of the other pieces.

While fighting the Forever Knights, Ben learns that his former bullies Cash and J.T. have started a web show with the aid of Oliver Thompson, claiming themselves to be the masterminds behind Ben's success. Ben reluctantly agrees to participate in the web show after Cash reveals that he needs the money for his mother's operation. The group learns that the Forever Knights are developing a power decoupler, a deadly cannon which absorbs energy from its surroundings. Ben and his team defeat the Forever Knights but are suddenly attacked by Psyphon, Vilgax's former subordinate, who saw the web show and wishes to kill Cash and J.T. to avenge Vilgax's death. At Psyphon's mercy, Cash reveals that the web show was a lie and that his mom only needed money for a nose job. Psyphon attacks Ben instead, but Cash and J.T. fire the power decoupler at Psyphon, defeating him. However, because the decoupler disabled Oliver's camera, there is no evidence that Cash and J.T. were able to defeat Psyphon, leaving them ridiculed.

Following the events of the previous episode, Azmuth contacts Ben's team and teleports them to the location of the final piece of the Map of Infinity: a huge, cube-shaped structure known as the Perplexahedron, located in another galaxy. The team pursues Aggregor to the interior of the Perplexahedron, discovering that it is an enormous, shifting maze designed by Professor Paradox to protect the final piece of the map from all who are unworthy. Ben eventually deduces a way to navigate the maze, and the trio are able to outmaneuver Aggregor and beat him to the center of the Perplexahedron. There, they meet the Sentinel, an alien who exists to protect the map piece. Ben retrieves the piece, causing the Perplexahedron to begin collapsing; while they try to flee, Ben decides to go back to save the Sentinel. In the process, Ben and Aggregor battle, and Aggregor steals the last piece. The Sentinel, lamenting that all is lost, vanishes in Ben's arms; Ben, resolving to honor him, declares that they will stop Aggregor.

On Galvan Mark II, Azmuth chastises Ben, Gwen, and Kevin for their failure to stop Aggregor from acquiring the completed Map of Infinity. Ben decides to turn into Alien X, his most powerful alien form possessing virtual omnipotence, in the hopes of stopping Aggregor; however, Ben is unable to convince Alien X's split personalities to cooperate, and Professor Paradox ultimately reverts Ben to human form. Paradox explains that the Forge of Creation is the birthplace of Celestialsapiens, the species of Alien X; Aggregor intends to absorb the powers from an infant member of their species, which will give him infinite power. Paradox teleports the team to the Forge of Creation, which is out of sync with time itself due to a chrono-randomization barrier. When Ben falls through the barrier, he accidentally summons a ten-year-old version of himself, who agrees to help them stop Aggregor. In the center of the Forge of Creation, the team battles Aggregor on the palm of a mother Celestialsapien, but all of them are defeated. As a last resort, the ten-year-old Ben convinces Kevin to absorb the Ultimatrix's power, turning him into a monstrous amalgamation of Ben's aliens. Kevin easily defeats Aggregor, but loses his mind and flees. Paradox returns the young Ben to his timeline, while the old Ben resolves to find and rescue Kevin.

Omnitrix alien debuts: Heatblast (10 years old), Wildmutt (10 years old), Four Arms (10 years old), Stinkfly

In the Eastern European monarchy of Zarkovia, Prince Gyula reveals to his father, King Xarion, that he has acquired the corpse of Dr. Viktor, and intends to weaponize it to crush internal rebellion in the country alongside Gyula's mind-controlled army. Xarion, fearing the prince, summons Ben, Gwen, and Kevin to remove Dr. Viktor from Gyula's custody. Gyula confronts them and unleashes Viktor, who is under his mind control, who quickly defeats and captures the trio along with King Xarion. Gwen helps Xarion escape, but Xarion betrays her and drags an unconscious Ben into his lab. Using AmpFibian, Xarion transfers his mind into Viktor's body, becoming "King Viktor," a virtually unstoppable weapon. King Viktor attacks his son and unleashes his wrath on the rebels, but is attacked and defeated by Ben, Gwen, and Kevin. However, they are unable to take King Viktor to the Null Void due to the Plumbers not having the authority to arrest Xarion. Gyula declares that he will hang King Viktor, but Ben frees Gyula's army from his mind control so that they can choose their own sides, then leaves the country with Gwen and Kevin.

• Ultimatrix alien debuts: Wildmutt (cameo) Heatblast (off-screen activation)

Ben, Gwen, and Kevin are summoned to the Plumbers' Academy to complete their basic training for Plumber duty, as they originally received their deputy Plumber titles on the field. At the academy, they befriend an alien named Tack, while Ben comes at odds with their instructor, a strict yet decorated Plumber named Magister Hulka. As they train, several incidents occur which lead Ben and the team to suspect that someone is targeting Hulka with the intent to assassinate him. Investigating, they eventually discover that the attacker is Kolar, a Tetramand and one of Hulka's old foes. Together, they defeat Kolar and send him to the Null Void. Ben, Gwen, Kevin, and Tack then graduate from the Plumbers' Academy and are made formal Plumbers, while Hulka gives Ben an award for his creative tactics.

• Ultimatrix alien debuts: Fasttrack, Diamondhead

In an alternate future, a different version of Ben 10,000 defeats Eon and seemingly destroys him using Clockwork's powers. However, Professor Paradox appears and reveals that Eon was merely sent back in time twenty years. In the present day, Ben, Gwen, and Kevin arrive at a museum to investigate a signal that the Ultimatrix received. They find a mysterious artifact and are attacked by ninja-like assailants who emerge from it; they defeat the ninjas, but before they can unmask them, the ninjas vanish. Gwen performs a spell on the artifact and sees into another reality (the world of Ben 10: Race Against Time), where Ben, Gwen, and Grandpa Max are confronting Eon. Paradox and Ben 10,000 then appear, explaining that the artifact is the Hand of Armageddon, a gateway that leads to different parallel universes. After being defeated by the Ben from Race Against Time, Eon began travelling between worlds, killing every version of Ben Tennyson he could find. The group resolves to destroy the Hand of Armageddon before Eon can enter their world; however, as the two Bens begin to destroy the device, Paradox realises that Eon is instead using their powers to open a crosstime breach. Eon emerges and is revealed to be another alternate Ben Tennyson, who has been absorbing other Bens and making them his slaves. He intends to gain enough power to replace the timeline with one where only he exists. However, Ben is able to destroy the Hand of Armageddon, seemingly destroying Eon. Ben 10,000 then returns to his timeline, while Paradox ominously warns Ben about "Old George," and the "creature from beyond."

Grandpa Max tells Ben, Gwen, and Kevin the story of how he first met Verdona and became a Plumber. In 1962, a seventeen-year-old Max is a pilot in the Air Force. After spotting a UFO, Max gives chase and shoots it down, only to crash his Lockheed F-104 Starfighter. Max's colonel threatens to discharge him from the Air Force, but Max is summoned by the general, who believes Max's story. He reveals that President John F. Kennedy intends to send humans to the moon in order to meet alien visitors on a level playing field, and invites Max to join the Apollo program as an astronaut. Max agrees, and later visits a bar to celebrate, encountering a beautiful girl named Verdona. Verdona is then attacked by a mysterious robot; Max helps her flee, and Verdona reveals that she is an alien, and that the robot is a Synthroid who kidnapped her in order to use her power to fuel his species' home planet. However, Verdona escaped when Max shot down the UFO. Max and Verdona try to escape, but the Synthroid captures her and takes her to his ship. Through their telepathic connection, Max follows Verdona to the ship, where he and Plumber Magister Labrid destroy the ship and the Synthroid and help Verdona escape. Verdona leaves Earth, but promises to one day return to Max.

The mysterious old man from "The Creature From Beyond" approaches Area 51 and breaks in, causing the entire facility to disappear. Ben and the team are summoned by Cooper Daniels to investigate, where they meet Colonel Rozum and discover a layer of metal at the bottom of the crater that doesn't originate from Earth. Rozum reluctantly reveals that beneath the metal is a holding facility containing hundreds of aliens, who have been illegally detained by the Air Force over the course of fifty years after being deemed a threat to national security. The group discovers that one of the prisoners, #775, has escaped and fled in a stolen Plumber ship. Ben, Gwen, and Kevin confront Prisoner 775, who reveals that he was captured unjustly by the Air Force, and while imprisoned, his family members were killed on his home planet. Believing he has nothing left to live for, Prisoner 775 resolves to kill Colonel Rozum in revenge, and travels to Patrick Air Force Base in Florida, where Rozum lives. Ben and the team intervene, and Ben uses Ultimate Wildmutt to defeat 775. 775 is arrested by the Plumbers, while Max chastises Rozum for unjustly capturing the aliens; Rozum justifies it as protecting the safety of the United States.

During a battle, Ben transforms into Ultimate Humungousaur and suddenly declares that he is not Ben, attacking Gwen and Kevin. The two subdue him and consult a psychologist about his behavior, who deduces that he is suffering from some kind of split personality disorder. Ben screams and vanishes in a flash of light, leaving only the deactivated Ultimatrix, which Gwen realizes Ben is trapped inside of. Gwen and Kevin are divided on how to rescue him; Gwen uses an astral projection to enter the Ulimatrix, while Kevin travels to Galvan Prime to seek the aid of Azmuth. Kevin reaches Galvan Prime and battles a Galvanic Mechamorph security system, yelling at Azmuth that Ben is a hero and his best friend. Azmuth, moved by Kevin's growth and maturity, agrees to help him. Inside of the Ulimtatrix, Ben encounters his ultimate forms, which claim that they possess their own lives and minds, and wish to kill Ben in order to free themselves from him. Gwen arrives and saves Ben from the ultimates, and the two pursue them to a fiery pit, which the ultimates demand Ben jump into in order to liberate them. Gwen threatens to destroy the ultimates, but Ben tells her to stand down, and realizes he must sacrifice himself so that the ultimates may live. Ben kisses Gwen and hurls himself into the fire; he regains consciousness outside of the Omnitrix, where Azmuth, Kevin, Gwen, and the ultimates await. Azmuth reveals that he has repaired the glitch that granted the ultimates erroneous sentience, and says that the Ultimatrix recognized Ben's sacrifice and freed both him and the ultimates. Azmuth agrees to take the ultimates to a planet where they can live in peace, and Kevin offers to buy food for his "best girl" and his "best friend."

• Ultimatrix Alien debuts: Ghostfreak

Ben, Gwen, Kevin, and a squadron of Plumbers confront the Flame Keeper's Circle, who are transporting Vilgax via truck. The Plumbers are defeated by the Esoterica, the soldiers of the Circle, and Conduit Edwards escapes with Vilgax. Ben and the team unmask one of the captured Esoterica, who is revealed to be Winston, the Forever Knight squire who was controlled by the Lucubra. Ben and the others confront Driscoll; they deduce that Dagon is real and exists in the other dimension where the Lucubra was from, and can now control anyone the Lucubra controlled at will. Dagon possesses Gwen and reveals that Vilgax is seeking his heart, which George cut out of him centuries ago, which will grant Vilgax limitless power. Driscoll reveals that hundreds of years ago, George fought Dagon and sealed him away, the origin of the myth of Saint George and the Dragon. George is still alive in the present day, possessing immortality, and has left the Forever Knights in order to retrieve his sword, which is buried in Dagon's heart. Gwen deduces where the sword is located, and Driscoll betrays them, then takes Winston and the other knights to the sword's location. At the location, a battle breaks out between the Forever Knights and the Esoterica, and Vilgax absorbs the power from George's sword and Dagon's heart. Dagon, possessing Winston, convinces Vilgax to break the seal; when Vilgax attacks the seal, Dagon absorbs him into his dimension, leaving the sword behind. George picks up the sword and his youth is instantly restored.

Techadon weapon master Inspector 13 kidnaps Ben in order to investigate the failure of the Techadon robots to kill Ben in "Greetings from Techadon." Gwen and Kevin attempt to rescue him, but a malfunction in the Ultimatrix causes them to turn into Ben's alien forms. As Ben is captured in the Techadon factory, Gwen and Kevin are able to infiltrate it, and together they fix the Ultimatrix and defeat Inspector 13.

Jennifer Nocturne aids Carl Nesmith in escaping from prison. Ben and Gwen pursue them across the country, with Ben believing Nesmith has kidnapped her, while Gwen suspecting she is an accomplice. They track down Jennifer's mother, who reveals that Jennifer's father abandoned her before she was born, and Jennifer herself left for a TV show at the age of 14 and never returned. Meanwhile, Nesmith, seeking to hide his identity from the police, meets with a veterinarian who gives him plastic surgery; Nesmith subsequently murders him, as well as a random driver. Gwen deduces that Jennifer is suffering from Stockholm syndrome and has begun to identify with Nesmith due to her feelings that her old life was empty and meaningless. Nesmith leaves a note with the murdered driver telling Ben to meet him at Nemesis Tower; at the tower, Ben confronts and defeats Nesmith, but Jennifer uses one of Nesmith's battle suits to attack him. Gwen then defeats Jennifer; Nesmith insists to Jennifer that she tell the police he kidnapped her so that she won't be arrested for his crimes.

Dr. Animo is unexpectedly paroled from prison and starts up a company selling eggs, which in fact contain mutant dinosaurs which he wishes to distribute around the world.

Ben transforms into Ultimate Way Big and attacks Dagon, but is defeated and nearly killed by Dagon's nigh-omnipotent power. Subsequently, Dagon electrocutes and disintegrates George with lightning, declaring himself victorious over his greatest foe. Vilgax suddenly appears and taunts Dagon into firing a laser at him, which Psyphon absorbs into the machine that Vilgax used to steal the powers of other heroes in Ben 10: Alien Force. Because Dagon's "substance is power," his entire body is absorbed into the machine, which Vilgax orders Psyphon to fire at him in order to grant him Dagon's power. Psyphon does so in spite of Ben's objections, and Vilgax gains the full power of Dagon, attacking and seemingly destroying Ben, Gwen, and Kevin. However, Gwen is revealed to have teleported them all at the last second to the decommissioned Plumber headquarters at Mount Rushmore. Moments later, Vilgax returns and attacks them, knocking out Kevin and Gwen. Ben takes Ascalon and wields its power, defeats Vilgax and absorbing Dagon's power from him. Ben is tempted by the virtually limitless power he now possesses, and on Vilgax's suggestion, contemplates wiping out all evil in the galaxy. However, Gwen, Kevin, and a recently arrived Julie dissuade him, and Ben gives up the power. Julie kisses Ben, and Azmuth arrives to reclaim Ascalon. Azmuth then destroys the Ultimatrix and gives Ben a new Omnitrix, asking him to keep doing the right thing.

• Ultimatrix alien debuts: Ultimate Way Big
• Noted: Series Finale March 31, 2012
• This episode was dedicated in memory of Dwayne McDuffie.^[b]

Benjamin "Ben" Kirby Tennyson teams up with sixteen-year-old Rex Salazar to save both of their Earths from a very powerful and deadly nanite-of-nanites called "the Alpha Nanite", the enhanced technological force of the Omega Nanite which resides within Rex's body, having integrated into his DNA one year ago that entered New York City through a swirling vortex from an entirely different alternate universe, the same way Ben Tennyson arrived in the city as Humungosuar. After a brief skirmish and getting to know one another, the two superpowered heroes of aliens and machines unite to put a stop Alpha's plan of draining Rex dry of his great and powerful Omega Nanite to dominate both realities with their combined power.

• Ultimatrix Alien debuts: XLR8, Shocksquatch, Upgrade
• Notes: The events of the crossover specials take place during the third and final season of Generator Rex.