The story of the tyrannical alien overlord and archenemy of Ben Tennyson, Vilgax, the overarching antagonist of the Ben 10 franchise.
Vilgax was feared across several galaxies for his conquest of a number of planets and destruction of five others, even making a black hole. No biological life form was willing to serve Vilgax, since they were all too afraid of him, so Vilgax was forced to make a crew of robots (with the occasional mercenary thrown in). At one point in the past, he managed to destroy the Petrosapein’s homeworld after Tetrax unwittingly gave him the final element he needed to do so. In the year 1773, Vilgax had been exiled from his homeworld for "ambitious disobedience." He is summoned to Earth by a distress signal sent by a time-traveling Maltruant. There, he makes repairs to Maltruant's damaged transport in exchange for a Chronosapien Time Bomb that he would use some time later. During this, Vilgax encounters George Washington and a time-traveling 16-year-old Ben Tennyson. Watching Ben transform into various aliens is what initially fostered Vilgax's interest in the Omnitrix, planning to use it as a means of creating an army with the abilities of every alien species in the universe at his command.
Later, Vilgax went to Earth, where he had a number of encounters with the Plumbers, a group of humans put together to fight alien threats, particularly Max Tennyson. Vilgax eventually tried to steal nuclear missiles from an army base, but Max and his partner, Phil, showed up. The alien ended up stuck to a nuclear missile and was launched into his own ship, but managed to survive.
Vilgax eventually tracked the Omnitrix to a ship under the command of Xylene and attacked in his own ship, the Chimerian Hammer. She couldn't hold his forces off; thus, she was forced to send the Omnitrix down to Earth, where it would be found by Ben Tennyson.
However, a time-traveling No-Watch Ben secretly used Grey Matter to sabotage the shield generator for the ship. The bridge of the Hammer was then blasted, inflicting severe damage to Vilgax's body, and he was placed in a repair tank to be healed, preventing him from going after the Omnitrix personally. He eventually learned that the Omnitrix was in someone’s possession and relied on his minions to get it back. Vilgax sent robotic drones, hired a trio of bounty hunters and even used a Earth criminal fused with one of his drones to try and get the Omnitrix. During Ben’s battle with the latter, Vilgax made a brief psychic link to Ben and warned him that he’d come after him one day. Finally, the alien’s body was not only healed, but granted cybernetic enhancement, increasing his strength. Vilgax went to Earth to personally obtain the Omntitrix, managing to beat and capture Ben. The alien was surprised that a human child was the one who’d resisted him so long and tried to obtain the Omnitrix. However, Gwen Tennyson and Max interfered and Ben lost control of his transformations, before they eventually set off the self-destruct in Vilgax’s ship with him inside.
In a non-canon episode, Ben found himself re-living the day he found the Omnitrix except Gwen found it instead. However, Vilgax wasn’t harmed by his battle with Xylene’s ship and went after the Omnitrix when his drone was defeated. The alien captured Gwen, but was beaten by Max and Ben, getting thrown into his ship by Upgrade, apparently killing him.
Future Conflicts with Ben
Vilgax survived the explosion of his ship, teleporting out before it blew up, but was somehow frozen, possibly due to the bitter cold of space. Kevin 11 found and freed him, and after a rough fight, Vilgax realized the connection Kevin had to the Omnitrix, agreeing to work with him. Vilgax and Kevin almost succeeded in taking the Omnitrix from Ben, but ended up trapped in the Null Void dimension. When Ben was in an illusion created by the Forever Knights, a dream version of Vilgax appeared to fight him. As they fought, the alien tried to send Ben to the Null Void, but Ben threw him inside instead. However, Vilgax’s actions tipped Ben off to what was going on since he was going to send him to the Null Void without getting the Omnitrix. In an another non-canon episode, after the summer was over, Vilgax and his drones went to Ben’s hometown and destroyed the boy’s home as a means to get revenge.
When Ben got back home, Vilgax showed up, threatening the life of his father, Carl, and forced Ben to reveal his secret when he became Cannonbolt. Vilgax retreated, but began attacking the city with his drones and Ben, Max, Gwen, and Carl worked together to fight off his drones. Eventually, Vilgax was lured into the underground bus line by Ben, where Carl dropped a lighter onto a gas line, incinerating the alien in a massive explosion.
10 years in the future (in what is now an alternate timeline), Vilgax escaped the Null Void via a Null Void portal opening on another planet. However, the future Ben didn’t want to take any more chances and in a final battle, left Vilgax torn to shreds. But 10 years later, Dr. Animo found what remained of the alien and resurrected him with his Transmodulator. With the moves of every alien Ben 10,000 had programmed into him, Vilgax engaged Ben 10,000 and was able to fight him. However, with help from his 10-year old self, who’d been brought to the future by the future Gwen, Ben 10,000 defeated Vilgax and froze him via his Arctiguana form.
Secret of the Omnitrix
Vilgax eventually managed to escape the Null Void after stumbling across a Null Void portal being opened, though it had a stressful impact on him. He also seemed to have a deeper grudge against Ben and eventually reattempted to regain the Omnitrix, which had accidentally been set into self-destruct mode by Ben, not acknowledging the danger the Omnitrix’s self-destruction posed. Vilgax began pursuing Tetrax’s ship, picking up the bounty hunter, Sixsix, outside Incarcecon and using him like a bloodhound. He eventually attacked Tetrax’s ship and confronted Ben, but was eventually shot out into space via the airlock. Vilgax finally managed to follow them to the planet, Xenon, but was defeated when Azmuth (creator of the Omnitrix) deactivated the self-destruct and gave Ben access to the form of Way Big. In this form, Ben defeated Vilgax’s forces and tossed him into space.
Five Years Prior to Omniverse
A flashback occurs where Vilgax is seen with a tied-up 11 year old Ben. Vilgax then threatens to feed Ben to his numerous squid monsters, but Ben breaks free and transforms into XLR8. The flashback ends with XLR8 being grabbed by a Squid Monster. What happened afterwards is unknown.
Resuming the Fight with Ben
Vilgax managed to return, now less cybernetically enhanced (as to how this happened is never explained) and with a new right-hand named Psyphon. However, he began following galactic law, which justified his takeovers if he defeated a champion of that world. Thus, Vilgax conquered 10 planets, including that of Ultimos, and absorbed the powers of each champion. However, Vilgax continued to be obsessed with the Omnitrix and went to Earth after defeating Ultimos. The alien managed to defeat Max and the Plumbers’ kids, but didn’t absorb their powers, choosing to use them as a message to Ben. Vilgax challenged Ben under the galactic code, giving him 24 hours to accept the challenge or he would be able to legally destroy Earth. Ben accepted and managed to get to the fight in time, despite his Omnitrix overloading and forcing him to recollect his aliens. Eventually, Vilgax managed to smash Ben to pieces as Chromastone, but before he could take the Omnitrix, Chromastone was reformatted into Diamondhead. Due to the practice he had with that form and his age, Diamondhead was able to defeat Vilgax, forcing him to leave Earth, never to return. However, he swore that he would have revenge on Ben one way or another. Later on, Vilgax freed Zs’Skayr in exchange for the secrets of the Omnitrix, only to be betrayed. Zs’Skayr invaded Vilgaxia, Vilgax’s homeplanet, and possessed most of the inhabitants, turning them into his Ectonurite minions. Vilgax failed to stop him, forcing him to go to Ben and his allies for aid and made an uneasy alliance. They managed to reach Zs’Skayr and Ben let the Ectonurite possess him so as to absorb him back into the Omnitrix. However, Zs’Skayr took over Ben’s personality and Ben’s friends and Vilgax fought him, arguing over whether or not to hurt Ben. Vilgax was finally able to weaken Zs’Skayr by generating light, which gave Ben control again, changing back into a human. Vilgax let Ben and his friends leave in peace, but gloated to himself that he’d finally gained the Omnitrix’s secrets.
Attack on Primus
Vilgax launched an assault on the planet Primus, which resulted in the Omnitrix teleporting Ben and his friends to Primus. The device then left Ben to find Azmuth, who used it to fight Vilgax, only to lose and let Vilgax take the Omnitrix. However, he didn’t know how to use it since the device was recalibrated and made Ben tell him how to use it by threatening Gwen and Kevin. But Ben made the Omnitrix turn Vilgax into Goop and took the artificial gravity device that let Goop move, causing him to become a motionless puddle. Ben took the Omnitrix out of the puddle, changing Vilgax back to normal. Ben then turned into Cannonbolt, throwing his archenemy into the Codon Stream, which contained all the DNA the Omnitrix accessed. Vilgax grew considerably larger, but Ben changed into Way Big, throwing him into space.
Return of Petropia
Vilgax eventually returned to normal size and began seeking Tetrax Shard, who stole the crystal Vilgax used to destroy Petropia. Tetrax had found out that the crystal was a back-up for Petropia and the Petrosapiens and intended to restore his planet. The conqueror tracked Tetrax to Earth and demanded that he give back the crystal he’d stolen. However, Kevin accidentally revealed that Tetrax gave it to Chromastone, (actually named Sugilite) who’d been freed from the Omnitrix. Vilgax followed him, finding that Petropia had been restored, and was enraged that the crystal had been used to revive a world he destroyed. Vilgax managed to beat up Sugilite, who begged the conqueror to have mercy and allow him to bring back the Petrosapiens. Viglax replied that he had no mercy and continued to beat up Sugilite until Ben, his friends, and Tetrax arrived. Vilgax managed to fight them and remove the crystal from Sugilite’s head only to find its energy was gone. The conqueror returned to Vilgaxia, seeing Petropia as a lifeless planet that was of no consequence, not knowing that Sugilite created a second crystal, which was used to restore the Petrosapiens. To add to the sting of losing the crystal, Vilgax found he’d gotten Ben’s cold.
Alliance with Albedo
Vilgax eventually joined forces with Albedo by telling him that he just wanted to kill Ben and the Omnitrix no longer interested him. Once they killed Ben, Albedo could have the Omnitrix so as to get back his Galvan form. With Albedo using the Ultimatrix, he and Vilgax defeated Ben, who managed to retreat after losing the Omnitrix to them. However, the conqueror turned on Albedo and managed to capture him, while Vilgax planned to use the Omnitrix on his army of Bioids- robots that could assume the alien form of whatever Vilgax put into the Omnitrix. However, Ben and his friends boarded his ship and Ben activated a lesser version of the Omnitrix’s self-destruct, one that would go off in 30 seconds and only destroy the device. Vilgax didn’t take the threat seriously and thus the Omnitrix detonated, prompting him to angrily send his ship on a collision course with Ben’s hometown. Vilgax then attacked Ben and his friends, but Ben freed Albedo, taking his Ultimatrix and using it himself to fight Vilgax as Ultimate Swampfire.
Max and Gwen managed to make the ship crash harmlessly in the ocean and Vilgax revealed his true form, changing into a gigantic, octopus-like monster. He almost managed to swallow Ben, only for his archenemy to escape while he was left in the explosion.
Vilgax managed to return yet again and was left in a weakened state due to the explosion, unable to regain his usual form. Eventually, he washed up on a beach where he was found and put in a carnival sideshow. Despite the indignity of this, Vilgax took the time to get his strength back until he was freed by the Esoterica, one of the 2 cults alongside the Flame Keepers' Circle. They both believed him to be Diagon, a legendary alien of knowledge that two cults worshipped and believed to have bestowed fire on humanity. The Circle worshipped him, hoping he’d bring a Golden Age of prosperity to Earth. Ben eventually found Vilgax, when he was investigating the Flame Keepers Circle and the alien informed him that he planned to take back his empire when he had access to a spaceship. Gwen and Kevin managed to disable a ship the cult stole from the Plumbers. They and Ben tried to tell the cult who Vilgax really was, but the group didn’t believe them and Ben swore to his archenemy that he’d stop him if he ever reattempted to escape Earth after shattering his tank. Vilgax later managed to obtain Old George’s sword, regaining his normal form, but covering himself in armor. Winston told him that breaking the seal that had once imprisoned Lucubra would grant him the power to rule the universe (a trick by Diagon to gain his freedom). Vilgax went to the seal, fighting off the Forever Knights as he did so, and was eventually confronted by Ben and his friends. Ben told Vilgax he didn’t know what he was doing, but the alien thought otherwise and managed to fight Ben off. However when he broke the seal, Vilgax was pulled into Diagon’s dimension. But while he was in Diagon's dimension, Vilgax became Diagon's herald, the most powerful of his followers. After St. George arrived at the seal, Vilgax appeared to fight him, easily taking him on and the other Forever Knights. When Ben as Heatblast arrived on the scene, Vilgax was easily able to fight him as well and eventually he cracked the seal, opening a portal to Diagon's dimension. The opening allowed Diagon to send out a wave of energy that transformed every person on Earth into his servants. However Ben, Gwen, Kevin and Sir George were not affected due to a mana field Gwen had put up and Julie was protected by Ship. Vilgax continued to fight them and eventually tried to completely destroy the seal. Diagon became angry at the amount of effort he was having to use since the power he'd given Vilgax should've been more than enough to destroy the seal. However Ben, transformed into Eatle, and St. George emerged from the rubble they'd been buried under and re-engaged Vilgax. Ben accused him of only helping Diagon because he wanted something for himself, making him angry and he knocked them aside. Eventually Kevin and Gwen arrirved to help and they all cornered Vilgax, demanding that he tell them how to stop Diagon. Vilgax asked his master to give him more power, only to be met with silence, but Psyphon arrived on the scene in a spaceship. Vilgax angrily said he was late, but Psyphon replied that it had been harder than he'd expected to gather what he'd wanted. However, Diagon arrived, appearing in the sky and claiming he was "everywhere". He ordered Vilgax to attack Ben and his allies, but he disappeared, going to prepare the machine he'd used to absorb powers earlier. After Diagon defeated St. George, Vilgax returned, saying he would rule his universe, as well as that of Diagon. Diagon attacked him and his machine, but it began absorbing his energy beam, continually taking in his power until it absorbed Diagon himself. Psyphon then transferred the power to Vilgax and apparently managed to destroy Ben and his allies, but Gwen actually teleported them away. However Vilgax's powers allowed him to instantly find them, following them to Mount Rushmore and sending his Esoterica to attack them. When they were driven off by the defense systems of the plumber base inside, Vilgax changed into his previous form and tore the Washington face away, disabling the defenses. He wrecked the base, defeating Gwen and Kevin, before facing Ben, who took up Ascalon, St. George's sword. They fought and Vilgax was changed back to normal, with Diagon's power being absorbed into Ascalon. He asked Ben what he planned to do with that power and when Ben said he was going to change the Esoterica back, Vilgax pointed out he could use it, along with the power of Ascalon and the Ultimatrix to rid the universe of evil. However Ben, with the encouragment of his friends, gave up the power of Diagon to return everyone on Earth to normal.
Vilgax eventually ended up as a prisoner of the Plumbers and was being escorted to Incarcecon. They even went as far as to evacuate all the prisoners to ensure he couldn't threaten or cajole anyone into helping him escape. As they approached the prison, Vilgax noted how he felt flattered, but they were attacked by the forces of the Incursean Empire, led by Princess Attea, who'd been attempting to conquer Vilgaxia and hoped to make them surrender by killing their leader. The ship managed to reach Incarceceon, but the Incurseans followed with Attea siccing Sixsix, Sevenseven, and Eighteight on them. Ben became angry, thinking Vilgax arranged for this, but Attea soon made it clear that she was trying to kill the conqueror. Ben managed to take down Attea and her minions, before the group escaped. As Ben and Vilgax walked down a hall, Vilgax pointed out that he was the reason Ben obtained the Omnitrix in the first place.
Ben replied he was always trying and failing to get the Omnitrix, only to get beaten again and again, asking Vilgax if he was seeing a pattern. As they started arguing again, Ben said he was considering just letting the Incurseans have Vilgax, but the conqueror pointed out that the Incurseans wouldn't stop with Vilgax and would go after every planet in the universe. However Attea and Eighteight caught up with them and Eighteight managed to trap the two. Vilgax commanded Ben to remove the restraints holding him, which he did. However the conqueror tossed Ben at Attea and Eighteight, before making his escape. Vilgax almost ran into Sixsix and Sevenseven, but Ben caught up with Vilgax and put the restraints back on him, despite his claiming he tossed Ben at them merely as a diversion, knowing Ben could defeat them. Ben decided to bring Vilgax to a different prison, only to again be attacked by Attea and the bounty hunters. Vilgax suddenly saved Ben from Attea's Techadon Dissipator and Ben and the Plumbers ended up defeating the Incursean forces. However Vilgax was freed and knocked Ben out, successfully escaping after failing to try and steal the Omnitrix.
Vilgax appears as a disguise for Lucy to scare Psyphon in Mud is Thicker than Water.
He also appears in Khyber's dream in For a Few Brains More, tied up in the back of the Rustbucket.
In Bengeance is Mine, a human plumber by the name of Bill Gacks, (who surprisingly looks like human version of Vilgax), accidentally activates a hidden device left by Vilgax as a contingency vengeance plan against Ben. The device released an army of Squid Monsters, which Ben had fought five years prior to the Omniverse series. Following the orders of Psyphon, the monsters began a havoc in Bellwood in the name of their master, but were eventually stopped by Ben, Rook and Bill Gacks disguised as Vilgax using ID Mask.
In And Then There Were None, Vilgax has allied himself with Eon to destroy every version of Ben from every alternate reality, taking several evil Bens from the multiverse as his agents. Vilgax encountered Good Ben at the insistence of Eon, who believed that a Tennyson without the Omnitrix was a wildcard that they didn't need ruining their plans. Midway through the battle between multiple Bens, Vilgax activated a Chronosapien Time Bomb, a weapon that would erase all version of Ben (including Eon) and erase every alternate timeline with the exception of Good Ben's. This would leave only Good Ben, the only one that didn't stand a chance against him. While Vilgax wasted time gloating about his superiority, Professor Paradox rescued Good Ben from Vilgax's wrath, taking him to a pocket dimension.
In And Then There Was Ben, Vilgax is first seen when No Watch Ben and Paradox go back in time to the day where everything began. In order to reboot the prime timeline No Watch Ben disabled His ship's defenses as Grey Matter. This allowed the ship to take a last hit from Xylene's ship, making sure that Vilgax mortally injures. Back in the present, he encountered No Watch Ben a few seconds after Paradox saved him and he was glad there was one Omnitrix left. He told No Watch Ben that he doesn't even know how to use it and never will be a hero. However, he turned into Clockwork and undid the effects of the bomb. Clockwork then send back the evil Bens to their own timelines, having Vilgax left alone. Vilgax was beaten by Ben Prime, Ben 23, Gwen 10, Ben 10,000 and was given a final kick by No Watch Ben. He was then taken into custody by Alternate Max and that timeline's Plumbers.
Sometime after that, Vilgax escaped from prison and returned to the main timeline.
In Universe Vs. Tennyson, he excitedly watched Ben's trial on his ship.
In Vreedlemania, Vilgax returned to get his revenge on Ben, but fled after he saw Ma Vreedle.
In Malgax Attacks, after Ben finally managed to remove Skurd from his Omnitrix, Vilgax and Albedo stole Malware's remains from the museum on Galvan Prime. They modified his genetic structure and turned him into a suit which Vilgax wore to defeat Ben Tennyson and obtain the Omnitrix. Vilgax had shown to have the upper hand until Skurd returned to help Ben. After their plan failed and Vilgax was mortally injured in the warm core's meltdown, Malware's remains start to ooze out of Vilgax's petrified body while Albedo had his Ultimatrix disabled and was sentenced to community service for the next "30 Galvan cycles".
In the reboot series Vilgax first appears in the season one finale as Vil and later steals Gax from Ben and had since became a recurring villain.
Ben 10: Protector of Earth
Vilgax is the main villain in the Game, he recruits Zs'Skayr, Dr. Animo, Kevin 11 and more. He sent a robot to earth and extracted DNA from the Omnitrix. He planned to send earth into the Null Void. Oddly Vilgax looked like how he did in the episode Ben 10,000, which takes place in the future.
Punch Time Explosion and XL
Vilgax conquers Chowder's World. Ben then reads a newspaper about Vilgax conquering Chowder's World and goes to stop him. Later Chowder and Ben find Vilgax with Mung who then explains how they are in another dimension instead of another planet. Eventually Vilgax teleports away and a dimensional crack appears and absorbs Ben, Chowder and Mung.
They are then teleported to Bellwood to defeat Buttercup in her Anti-Form. After traveling through caves, blasting with turrets and exploring the Null Void the team finally face Vilgax. Unfortunately Vilgax teleports the team to Primus and summons Ultimate Kevin to destroy them.
When Vilgax is defeated, he flies away from a sinking ship leaving cured Number 1. The heroes then fight Negative Samurai Jack and Vilgax in order to defeat a greater evil.
Ben 10 Alien Force: Vilgax Attacks|Ben 10: Vilgax Attacks
Vilgax, instead of trying to conquer Earth like in Vengeance of Vilgax, looked for sub-energy orbs to power his Null Void Projector to send Earth into the Null Void. Ben destroyed all the orbs and Alien X sent Vilgax and Psyphon to the Null Void.
Ben 10: Race Against Time
Vilgax appears as a boss in the game.
Ben 10: Galactic Racing
Vilgax is a Playable unlockable character. He uses his laser eyes to attack other racers.
Ben 10: Omniverse
A robot replica of Vilgax appears as an enemy.