When Timmy Turner wished he was in the greatest science lab in the universe, Cosmo and Wanda poof him into Jimmy Neutron's lab. Jimmy was seen updating Goddard with a new upgrade. But after Jimmy put Goddard in sleep mode to update him with his new upgrade, he runs into Timmy and he falls into Jimmy's Hypercube while arguing with him. But when Jimmy picks up Timmy's poofer, he accidentally poofs himself back into Dimmsdale.
After Timmy pops back out of Jimmy's Hypercube, he starts to mess with his inventions. When Timmy sees Goddard, he mistakes him for a dog shaped video game console. He thought Goddard's new upgrade was a video game Timmy called boring and took the upgrading disc out and replaced it with the disc of a violent video game called, Decimator. A video game about a giant evil destroying everything robot that destroys the world.
After a few minutes of downloading on the Decimator video game instead of Goddard's new upgrade, he transforms from a robot dog to the giant Decimator robot, and when the downloading finishes, he breaks out of Jimmy's lab. Goddard, now a giant, talking killer robot with red eyes, crushing feet, grabbing claws and with dangerous weapons (he still had his dog head) starts to terrorize Retroville. Decimator Goddard's first victim was Hugh Neutron.
Decimator Goddard knocks out Hugh and grows a few inches. He then destroys a driver's truck and the Retroville Mini-Golf Course windmill. Goddard then starts to attack Carl, Sheen and Libby. Goddard grew bigger and bigger every time he defeated a victim. When Goddard approaches the Retroville Park now gigantic where Timmy and Cindy were dating, he spits magma at the kids and then he eats Timmy.
Timmy now inside Decimator Goddard, gets the help from Cindy to shut the giant destroying everything Goddard down. Goddard approaches the Purple Flurp Factory and was about to destroy it with his rockets, but Timmy, with Cindy's help, was able to flip a switch which was able to shut Decimator Goddard down. Goddard now turned off falls down to the ground and Timmy makes it out of him.
Goddard then shrinks back down to his robot dog form. Goddard was now a robot dog again. When Goddard was now back to normal, his screen opens and Timmy and the others see Jimmy now in 2D and in Fairy World. When Timmy asks Jimmy what is he doing in Fairy World, he explains that some lunatic sucked him, and Timmy's 'computer programs' into a 'computer simulation'. Timmy gets extremely shocked when he finds out Crocker is in Fairy World.
When Jimmy finds out Timmy turned Goddard into the giant Decimator robot that almost destroyed Retroville, he gotten very angry with him asking him, "What kind of Genius are you!?". But Cindy then tells Jimmy not to worry and explains Timmy already saved the day and his dog. Timmy then later on apologizes to Jimmy for turning Goddard into the giant Decimator robot and for breaking into his lab. When Timmy and Jimmy were then returning back to their home dimensions, Jimmy thanks Timmy for saving Goddard.
By the end of the episode, Jimmy teleports Goddard into Dimmsdale for Timmy to use as his Science Fair Project.
- When Goddard turned into the Decimator robot, he was voiced by Dan Castellaneta, the voice actor who voices Homer Simpson and many other characters from The Simpsons.
- Decimator Goddard's magma canon was similar to Robo-Fiend's magma canon he used in the episode, Ultra Sheen.
- Decimator was revealed to be Timmy's favorite video game.
- The name of the destroying everything robot Decimator, was taken from the title of the Terminator movies.