Viral is a female computer virus and one of the recurring antagonists in Teenage Mutant Ninja Turtles: Fast Forward.
She is voiced by Eva Christensen.
Viral first appeared in the episode "Home Invasion," where she first appears at a local power substation, happy to see that she was free. She then goes over to Cody's penthouse and attacks the turtle in their battle simulator. Luckily, Donnie and Cody were able to cut off the power. As Viral attacks, the Turtles gang up on her - pleased that she is now in a physical body that can take real damage. With nowhere else to upload to, Viral cannot escape the ninja onslaught. A very damaged Viral makes a run for the elevator, but the Turtles catch her and kick her down the deep elevator shaft.
However, she reappeared in the body of a battle dummy. The turtles fought Viral and damaged her body badly, forcing her to retreat. After her defeat, she is unable to leave the body, so she contacts her master, Sh'Okanabo. However, her master refused to free her as he said it was her punishment for failing. While this attempt did not reap results, it's obvious that Sh'Okanabo won't be giving up any time soon...
At the beginning of the episode "The Freaks Come Out at Night," she watches her master implant his genes seed onto a pigeon, mutating it into a monster. However, at the end of the episode, Sh'Okanabo was shocked and outraged after his plan of using the gene seed to mutate everyone went wrong. Viral revealed to him that the cause of it was sun's radiation combined with the earth's oxygen atmosphere, outraging Sh'Okanabo even more.
Later in the episode "The Gaminator", she watches Cody and the turtles at a game convention, where they are awestruck by a high tech game system called Gaminator. She returns to Sh'Okanabo to tell him about a plan to destroy the turtles, once and for all. She sends them the video game system, and the turtles become excited over it. However, as they start to play it, their minds become trapped in it and are seen inside a video game. Viral then reveals herself to them and traps them in a cage.
The Turtles and Serling arrive in the next environment, the futuristic city Copinator game. Our heroes discover that they've landed in the middle of the "big boss" level - with a 50-foot-tall Viral as the boss.
As Viral grabs all four Turtles and once again begins uploading them to Sh'Okanabo, Cody quickly codes in a cheat code. Serling is given a glowing cheat orb that Jones tells him to toss at the villain, which he does. Viral is hit by the orb which zaps her and shrinks her down to size. Cody continues his hacking and the Turtles' weapons appear. The TMNT grab their gear and start some hacking of their own, cutting off Viral's arms. It appears that our heroes have won the battle, but the villain informs the Turtles that she controls the game and has unlimited health! Viral's arms reappear and she grows back into her super size.
The TMNT tell Jones that they're going to need "extra lives" - which gives Cody an idea. The boy scientist codes frantically. Suddenly, armies of duplicate Raphs, Leos, Mikeys, and Dons appear! The swarms of Turtles attack Viral en masse, covering her like hungry ants. Viral can’t handle the overload and aborts the mission as she surges out of the game
Later in the episode "Night of Sh'Okanabo,"Viral manipulates the grid and make it opaque, thus blocking all sunlight to planet Earth. She contacts Sh’Okanabo to inform the plan is going perfectly and we find that he has just captured Leo and Mikey!
Cut to the moonbase control room as Bishop and Turtle X arrive. Viral instantly attacks Cody, trying to take control of Turtle X, but Cody has installed a program that captures the villain and decompiles her code bit by bit. Viral is destroyed and Bishop accesses the Atmospheric Protection Grid and returns sunlight to the Earth.
Viral hacks into the system she's trapped in and finds Donatello and Cody trying to repair the time window, so the Turtles can go back to their own time. After seeing that the monitor she's seeing Cody and the turtles at is from Serling's point of view, Viral concludes that she's still inside of Serling from their last encounter on the moon. Viral then reveals that the decompiler program that seemingly killed her did greatly damage her, but her advanced systems managed to keep her alive and after some time has gone by, Viral's damages are 97.005% healed. Viral then vows to take revenge on the turtles but then, it appears that Cody and Don have completed repairing the time window and the turtles will be on their way home. This news pleases Viral, as it gives her a perfect chance to make the turtles suffer to the fullest extent.
Viral emerges out of Serling and enters the time window herself, infecting it and taking complete control over it. Upon Viral entering the time window, it explodes, taking Serling into it. In the time window, Leo suspects something might be wrong after he saw a surge of red energy enter the time window. The Turtles, Splinter and Serling almost make it to their time, but Viral alters the time window and sends them to a different time instead. The first time period Viral sends the turtles, Splinter and Serling to is the jurassic period, complete with a hostile dinosaur. Leo suggests for Serling to use his weapons, but Serling sadly admits that while inside him, Viral had disabled all his weapons
Donatello used a coil from the Utrom Shredder's exo-suit to reboot Serling, using his decompiler to once against destroy Viral. But as they race back to their proper time, a part of Viral appeared in Serling, using the decompiler on the other Turtles who were not inside (as in the time stream they are temporal data). But Splinter takes the blow just as they return. Viral then escapes from Serling into the Internet, where she attempts to locate a better power source to help her recharge and finish off the Turtles.
After much searching, Viral comes across a red and black data vault, containing a power source more than capable of healing her wounds. Viral attempts to access the data vault, but is unable to for unknown reasons. In the center of the data vault lurks something very odd: the Foot symbol! A virus emerges from the Foot symbol and immediately infects Viral. Viral's data and program are rewritten and reformated, her body begins to swell and red claws begin to burst out of her wrists and the backs of her legs. Finally a mysterious figure breaks out of Viral's infected body, killing her. The figure is revealed to be none other than the Shredder, in a new cybernetic form, (who will later to be the Cyber Shredder).
It is later revealed in the season finale that Cyber Shredder had inherited many of Viral's digital properties, such as her digital core, which enables her to escape harm. This allowed Donnie to figure out a way to decompile the Shredder, putting an end to his newest incarnation and Viral for good.