The End of the Universe-ity is the thirteenth episode of Season 6.
After failing to destroy the Earth once again, Dark Laser decides to get Timmy to join his side instead by tricking Timmy into wearing a dark suit that allows him to perform actions Da Rules normally wouldn't let him use Cosmo and Wanda for.
The episode starts off with Dark Laser trying to destroy the Earth by means of a powerful laser. However, Timmy is alerted of his attempts by an alarm, and he wishes for there to be a mirror in front of the Earth, redirecting the laser back at Dark Laser's ship. Undeterred, Dark Laser tries again to destroy the Earth with more powerful lasers, so Timmy wishes for the Earth to be located on the other side of the Sun. Still determined to completely decimate the Earth, Dark Laser tries yet again, only to have Timmy wish that his laser was a self-destruct mallet, causing the Death Ball to get severely pummeled and battered. Consulting with his staff, Dark Laser realizes that it is Timmy's fairies who give him powers that enable him to anticipate and counteract his every move. One of his advisers suggests turning Timmy to their side, which will enable him to destroy Earth.
Dark Laser turns up on the Turners' doorstep, claiming to be a professor at Dark Mouth University who is ready to offer Timmy a scholarship. After fooling Timmy's parents, Dark Laser then attempts to lure Timmy Turner into joining the dark side by giving him a suit that utilizes Dark Powers, expecting him to be so amazed with its powers that he'll choose it over his fairies and his morals. If he returns it after twenty-four hours, then Dark Laser will promise not to attack Earth again. Deciding to do so, Timmy wears the suit, using Dark Powers to do things magic can't as restricted by Da Rules, such as winning the science contest by destroying everyone's projects, slamming Francis repetitively into a locker, forcing Trixie Tang to kiss him by controlling her, and making Vicky his servant.
Soon enough, Timmy becomes a slave to the Dark Powers and is given the honor of destroying Earth by Dark Laser. Wanda tells him not to do so, reminding him to think of his god family. Right before pressing the activation button, he realizes she's right, and he rips it out instead, takes off the suit, and demands that Dark Laser hold up to his end of the bargain. However, possessing a dark power he forgot to mention(lying), Dark Laser had no intention of doing so and assembles his army of robots. Unfortunately for him, he forgot to reclaim the suit, which Timmy uses to contain his army in cages, conjured up by his fairies. However, Dark Laser managed to reclaim the button to fire the laser. Timmy then simply wished the laser to go in reverse, destroying the Death Ball instead.
Back on Earth, Timmy decides to use dark powers for emergencies only, which he does when Vicky turns up, making her flush her head in the toilet.