Cody has built the Turtles a holo dojo to practice in, but as they eagerly try out their new virtual reality practice arena the power goes out in the building. As Don and Cody investigate a sentient computer virus called Viral starts taking over all the electronic systems in the building, including the dojo, trapping the others inside.

''First appearance of Viral and Sh'Okanabo.''
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!! This episode provides examples of

* BackStab: Raph stabs Viral's physical form in the back with his sai.
* {{Expy}}: The virtual elves and troll Leo fights in the beginning bear a strong resemblance to [[Franchise/TheLegendOfZelda Link and Ganondorf]].
** Another simulation in the dojo is an obvious reference to ''WesternAnimation/WildWestCOWBoysOfMooMesa''.
* FallingChandelierOfDoom: How Leo takes out the troll in the opening battle simulation.
* HardLight: While at least some of the enemies in the dojo are physical practice bots, the inanimate objects and probably many of the other enemies appear to be this.
* HolodeckMalfunction: Engineered by Viral, holding Leo, Raph, Mikey, and Splinter hostage to force Cody to give up the password.
* HurricaneOfPuns: Surprisingly done by ''Leo'', of all turtles, as he lets loose with a stream of short-themed puns while fighting the elves, followed by a "Lights out, big guy" as he drops a chandelier on the troll.
* LamePunReaction: Don to Mikey, when the latter says:
-->'''Mikey''': Hey, if you can't stand the heat, stay out of the kitchenbot!
-->'''Don''': Okay, that was lame even for you.
* NeverSayDie: Averted in this episode.
-->'''Raph''': Are we dead? This don't feel like dead.
* UnusuallyUninterestingSight: The power station workers, upon seeing a massive power spike resolve itself into a face that shrieks "FREEEEE!" Probably combined with some BystanderSyndrome.
-->'''First Technician''': What the heck was that?
-->'''Second Technician''': I don't know, but it seems okay now. Uh, let's take lunch.
* UnwantedAssistance: Raph feels this way about all the helpful AI appliances.
* VirtualTrainingSimulation: Cody's custom-built dojo for the Turtles.
* YouFightLikeACow: [[LampshadeHanging Lampshaded]] by Michelangelo.
-->'''Viral''': You! You dare to mock me?
-->'''Mikey''': Yeah, it's sorta what we do in between kickin' butt!
* YouJustHadToSayIt: From Raph to Don, when the latter asks Cody if there was anything else in the building that Viral could inhabit while the power was shut off.
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