Ben, is the grandson of Maxwell Tennyson, now a friend to his former enemy Kevin, and a cousin of Gwen Tennyson. Ben was an average ten-year old kid until he accidentally found the Omnitrix, an alien device that allowed him to turn into ten different alien species. With the powers of the Omnitrix, he began his long career as a crime fighter, saving the universe multiple times.

He and Rex Salazar (both created by Man of Action) later had a crossover special where Ben was pulled into the world of Generator Rex and joined Rex in fighting a new threat. (Rex at first thought Ben himself was the threat when he took one of Ben's alien forms for an E.V.O..)

In FusionFall, Ben is one of the four guides. His missions entail trying to stop Fuse from getting his hands on alien technology on Earth. 


Arrival of Fuse

In FusionFall, after the first Terrafusers landed on Earth, ten-year-old Ben (as Four Arms) teamed up
Ben transfoming

Ben transforming into Four Arms

with Dexter to defend Foster's Home, Mac, and Bloo from the Fusion Spawn invaders. With the help of Professor Utonium, Dexter developed plans for an Electronic Pulse Cannon to disable the Terrafusers. Unfortunately, two key parts to the EPC were in the custody of both his nemesis, Mandark, and the villain, Mojo Jojo. Mojo's lair was raided by a team consisting of Ben, Numbuh Two, Bubbles, and Blossom. Ben was able to bypass Mojo's security system as the Galvanic Mechomorph he called "Upgrade."

Despite a Fusion Spawn attack, the part was recovered without a hitch. Ben (once again as Four Arms) then helped defend Dexter's ship against the Fusion Spawns in order to buy him and Professor Utonium time to fire the cannon. However, due to a miscalculation by Mandark, the cannon was too late to stop the Terafusers from summoning Planet Fusion and its army to Earth.

War Against Fuse

Ben Pad hologram

Ben bringing the hero up to speed on what a threat planet Fusion is.

The Future

In the Future, Ben and Numbuh Five help combat the Fusion Spawns at the Battle of Tech Square. They find the hero/heroine in the middle of the battlefield as he/she wakes up from Dee Dee's meddling with Dexter's time travel experiment. He and Numbuh Five teach the Hero/Heroine about basic combat when they run into some Fusion Spawns and a Cyberus. They leave to help out the other characters fighting in the battle while the hero goes to help out Numbuh Two. After the Tech Square battle it is unknown what happened to Ben. Thus, he is presumed dead.

The Past



In the past, Ben is in Offworld Plaza, serving as one of the four guides whom players can choose to work for. He is constantly lending a hand in the fight against Fuse and his minions, whether he is fighting, helping his Grandpa Max create his satellite to survey Planet Fusion, or cleaning up the Space Port in order to take the war directly to the Planet. He is also unaware of Princess's crush on him.

Omnitrix Problem

Ben is having more problems than usual with the Omnitrix, which started acting strangely as soon as Planet Fusion appeared. With a basic understanding of how the Omnitrix works, Dexter helps to keep the Omnitrix stable when it starts to go haywire. When Ben is able to use the Omnitrix, Fusion Gwen always appears to steal a piece from his alien hero forms, such as a talon from Jetray, fur from Spidermonkey, a stone from Chromastone, or a swamp root from Swampfire, presumably in order to create Fusion versions of them. Later it was shown Fuse had also stolen a scale from Humongousaur, and had earlier acquired a barbell from Four Arms. It is revealed by Paradox that Vilgax is the one who figured out how to disrupt Ben's Omnitrix (with the unintentional assistance of the hero/heroine) by somehow blocking the Omnitrix's signal from Primus. Together with Paradox, Azmuth, and the Ben 10 crew, the hero/heroine will try to get Ben's Omnitrix back to normal.


To better combat the invasion, Ben has made uneasy alliances with his mortal nemesis, Vilgax, his evil double Albedo, and Gwen's mortal enemy, Hex. Also, his Pyronite friend Alan, the Petrosapien warrior Tetrax, Ben's girlfriend Julie, her Galvanic Mechomorph pet Ship, his alien forms-among them, the powerful Alien X and the multiplying Echo Echo-the mischievous alien Megawhatt, creator of the Omnitrix and Ultimatrix Azmuth, and the time traveler Paradox have come to help out with the war as well.

Alien Abduction (Swampfire Nano Mission)

After a series of robberies by Fusion Gwen, Ben believes that she is trying to make Fusions of his alien alter egos. He sends the hero/heroine to recover stolen DNA from the Fusion in Steam Alley. Defeating and getting the stolen alien DNA, the hero returns to Ben with the samples of the aliens. After receiving the samples, he sends the Chromastone Crystal, Spidermonkey Fur, and Jetray Talon to Dexlabs for Nano creation. He gives the Hero one last objective: Defeat Fusion Gwen and use the Swamp Root to create a Swampfire Nano. The Hero infiltrates Fusion Gwen's lair, and after she has been defeated, it is revealed the she doesn't have the Swamp Root. Searching further, the Hero finds that Fusion Ben has the root and is working with Fusion Gwen. After a furious battle between the two, the Hero defeats Fusion Ben and creates a Swampfire Nano.

Nano Development

Trying to make more Nanos, or improve already created ones to win the war, Dexlabs and Mandark Industries create a group of Dexbots and Mandroids to get DNA samples from various characters such as Grandpa Max, Numbuh One, Ace, and Mojo Jojo. Mandroid M-99 in City Station sends the hero to obtain a sample of Ben's DNA or something he treasures most to create a Nano of him. Ben is forced to give up his Sumo Slammer card in order to create his Nano. Though he says that he'll miss it, he still gives it away.

Ectonurite Encounter

Some time later Ben becomes increasingly concern that the Planet Anur Phaetos (the homeworld of his Ectonurite alien transformation Ghostfreak) may be in league with Fuse in the plot to control Earth. Ben sends the Hero to talk to Vilgax about Ben's theory. Vilgax refuses to talk unless the Hero can obtain a DNA sample of the local Fusion monsters in the area. Ben devises a plan to get a DNA sample of the Fusion monsters, but use the Omnitrix to render it inert, asserting that Vilgax will never know. The hero ventures into the skypad infected zone and gets a sample of the Sawbreaker. Successful in his/her mission, the Hero returns to Ben and gives the sample to Vilgax, causing Vilgax to tell what he knows.

After this, Ben sends the Hero to Galaxy Garden after having received information from Max that there is a Plumber stationed there who has a device the can detect any Ectonurites that try to enter the Earth's atmosphere. Again the hero ventures to Galaxy Gardens to talk to Plumber Nathan. After the hero meets with him, Nathan says that he has what Max needs, but it's in the infected zone. Going in after it, the hero returns with the device to Ben, who now needs it to be set up.

Into the Chimerian

Not in Retro Large
Not in FusionFall Retro. The following section is about something that appeared after the Academy update in FusionFall, and so will not appear in FusionFall Retro.
As such, it solely exists for archiving part of the original game.

While the hero successfully frees Chromastone and Echo Echo from Vilgax's claws, Ben discovers another alien signal coming from Vilgax's ship. This time, Ben has chosen to come along with the hero to help rescue the last alien. As Echo Echo, he guides the hero while Kevin and Gwen handle Vilgax's security measures and maintaining portals and platforms, etc. The two then split up to cover more ground (inasmuch as Echo Echo can multiply himself).

When the hero looks elsewhere, he/she finds that Vilgax has come up with a way to activate his Bioids without the Omnitrix. The hero uses his/her NanoCom to take readings of the Bioids and defeats a few. The hero meets up with Ben at a waypoint and the two once again split. Ben explains that Vilgax is somehow hijacking the signal that the Omitrix receives from Primus with a receiver device of some sort. The hero gets a receiver from the Bioid Echo Echoes and gives it to Ben. 

Echo Echo Vilgax's Ship

Ben (Echo Echo), onboard the Chimerian.

Now that Ben and the hero have the receiver, Kevin thinks that he can disrupt the signal remotely using Ben's Omnitrix. Lastly, the Hero/heroine frees Ultimate Swampfire from his holding tub. The two regroup back on Ship.

A New Beginning

Not in Retro Large
Not in FusionFall Retro. The following section is about something that appeared after the Academy update in FusionFall, and so will not appear in FusionFall Retro.
As such, it solely exists for archiving part of the original game.
830px-Ben Null Void

Ben in the Null Void Training area.

After a series of warning messages from time portals all over and the hero's coming back with the blueprints for Nano, Dexter decides to take action quickly and stop Fuse's invasion before it advances. DexLabs, with the help of the Plumbers and Providence, create a training courses to help upcoming heroes train to fight Fuse. Ben and a handful of other heroes join the project. Ben has undertaken the task to help first level newcomers adjust to a life of fighting Fuse in the Null Void training area. He teaches the cadets about the basic things such as Resurrect 'Ems and fighting Fusion monsters. After the recruits complete a series of tasks, Ben believes that they are ready to fight a Fusion boss. With the help of Dexlabs, the Plumbers, and Providence, the resistance have managed to capture Fusion Finn, who had been lurking around the area and attacking heroes. The recruit is sent to defeat him and create a Finn Nano. After victory against Fusion Finn, Ben sends the recruit to the Providence Petting Zoo for further training.

Defender Amp Fuse (AmpFibian Nano)

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Not in FusionFall Retro. The following section is about something that appeared after the Academy update in FusionFall, and so will not appear in FusionFall Retro.
As such, it solely exists for archiving part of the original game.

Fusion Ben

Sometime later in the war, Fuse has managed to rob DexLabs and steal the sample of the AmpFibian DNA they were using to create a Nano of the alien. Professor Paradox tasks the hero with tracking down the DNA before Fuse is able to create a Fusion AmpFibian. His efforts are in vain, and before he is able to stop Fuse, the Fusion overlord has already created a Fusion AmpFibian. The Fusion AmpFibian is defeated and the hero creates an AmpFibian Nano.

Let Me Tell You Something About Rath! (Rath Nano)

Somehow Albedo is able to find an Appoplexian (similar to Ben's alien, Rath) and set it loose on Mojo's Volcano. A furious Mojo Jojo blames Ben for the attacks on his base. Grandpa Max, not believing the claims, sends the hero to investigate. Not being allowed in, the hero looks to the Rath Fan club for help. The hero talks to the Rath Fan Club President who sends him/her over to Rath Fan #23. Rath Fan #23 sends him to defeat Spawn Simians for his stolen entry tickets. Following on this success, the hero breaks into the volcano and finds out that Albedo is behind the plot to frame Ben. The hero makes quick work of him, clears Ben's name, and creates a Rath Nano.

Ben's Car

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Not in FusionFall Retro. The following section is about something that appeared after the Academy update in FusionFall, and so will not appear in FusionFall Retro.
As such, it solely exists for archiving part of the original game.
DX Mark 10

The DX Mark 10 in Ben's car in Ben 10: Ultimate Alien. It made its first appearance in the live-action movie, Ben 10: Alien Swarm, as a reluctant gift from Kevin. In the game, it can be seen next to Kevin's car on Mt. Neverest.



  • Ben is unique as he is the only Guide with more than one Nano of himself. Though his standard human form is not an available nano, six of his aliens are.
    Ben 10 Nano

    Nano of ten-year-old Ben Tennyson (not available for use)

  • Interestingly, all of his Nanos are Cosmix, excepting Rath, who is Blastons.
  • After the events of "Space Port Pickups," it was said that a Nano of his fifteen-year old self was in development.
  • Originally, Ben was going to be ten years old. However, with the release and popularity of Alien Force, the developers replaced him with his fifteen-year-old self. Swampfire and Humungosaur Nanos were originally to be Ghostfreak and Upgrade; however, they were replaced as well. There was not enough time to replace Four Arms. Furthermore, the younger version of Ben (and therefore, the younger Ben's aliens) were in the comic.
  • A Nano of young Ben was planned to be released around the time of the update before the game's release, but due to the replacement of young Ben, he was scrapped.
  • A plush toy found in the Ice King's castle is of a Waybig Nano.
  • Like the Scotsman, Professor Utonium, and Courage, Ben's Fusion is fought twice in the same area (Offworld Plaza) though unlike the other three, the real Ben is also located in the same area.
  • Alien X is the only Ben 10 Nano that can be received with a code.
  • Ben, Finn, and Bubbles are the only characters whose Fusion counterpart gives out two Nanos: Alien X and Swampfire.
  • He is one of four NPCs to give out two Nano missions. The other three are Dexter, Lance, and Grandpa Max.
  • In-game, Ben doesn't wear the Ultimatrix or new Omnitrix, despite both series starting and ending after FusionFall's release.
  • In FusionFall Heroes, players can play as Feedback, an alien form only appearing in Ben 10: Omniverse.