When Gumball is given a cursed video game console, Elmore becomes trapped inside a fantasy RPG world. Gumball, Darwin and Anais have to battle their way through town, unraveling the secrets of their new virtual reality.
To make up for not getting a present for Gumball's birthday, Richard gives him a knockoff video game console called "The Game Child," which he got from the Awesome Store. Gumball's slightly disappointed, but Richard reminds him how everything in their home is a knockoff of something and leaves. Gumball turns on to find the game within the console is Inverted Paradox: The Enemy Within, a JRPG. When Gumball starts the game and selects to go to the bedroom, he finds the world around him starting to pixelate into blackness which terrifies him.
When the screen is back up, Gumball finds himself in his room, where Darwin asks him what his name is. Gumball looks at the screen and realizes he trapped all of the town into the video game. He calls himself MYBUTT, causing Darwin and Anais' dialogue to sound funnier. Darwin and Anais join Gumball to fix the universe that Gumball messed up by turning on the video game.
They walk outside and encounter a shrub blocking their path. After seeing their limited options, Gumball kicks the shrub, forcing the team to go into a battle with a large, flower monster. Gumball acts overconfident before being damaged by the monster. Anais suggests damaging the creature with fire and activates Science, where she mixes two chemicals and throws it at the monster, which burns it away and gives the trio the victory. When they enter back into the neighborhood, they find out that the monster was Leslie, who was briefly changed into the monster after buying some fertilizer from the Awesome Store. When they get tired of Leslie talking, Gumball takes the dialogue captions to knock him out and the three run away.
They go to Mr. Robinson's house, where Gumball starts looting the place since he can get away with it in JRPGs and takes the old man's VHS player. Despite Anais and Darwin objecting, Gumball is proven right when Mr. Robinson tells them it's okay to take anything they'd like. Gumball takes a break by sleeping on Mr. Robinson's bed.
The siblings go outside and discuss possible outfit options for Anais. Gumball bumps into Penny, who challenges them to a fight with an electronic object stuck to her head. Gumball refuses to fight her, but Darwin tells him that's the only way they can progress. As Penny charges her attack, Gumball tries giving her the VHS player as a gift, which knocks Penny out and gives the team a bittersweet victory. Penny, now with a dented head, thanks Gumball for saving her and gives him the smartphone she got from the Awesome Store that possessed her to help him on his quest, which can summon allies to the battlefield. Gumball apologizes to Penny for disfiguring her with the VHS player and gives her a kiss before they leave. Penny passes out shortly afterwards.
They find the Crocodile Woman, whom Darwin thinks has a clue for them. She asks Gumball to find her missing pigeons, which are all over the town. Gumball is distraught, as the tedious sidequest preys on his gamer weakness of the need to 100% complete the game. After finding all the pigeons and becoming a fat nerd, Gumball receives the "No Life" trophy.
In the world map, Darwin spots the Awesome Store to the West under a thunder cloud. Gumball suggests that the three grind by defeating menial enemies to improve their stats. After defeating some small woodland creatures in the park, they take out some bystanders to increase their levels enough to take on the Awesome Store. They head towards their destination, but not before jamming out to the battle music one last time.
The Watterson siblings arrive at the mall parking lot, where Gumball forgot to save before they entered the cutscene to take on the Awesome Store. The Van Shopkeeper greets them and begins explaining something, but the children don't listen and immediately destroy the van. The Shopkeeper tells them that he is not the enemy and that the Game Child is the true villain of the game. The console comes to life and challenges the trio to one, final battle.
The last boss turns out to be very powerful, as it knocks the three of them down to 1 HP with one attack. Gumball tells Anais that if they lose, they either die in the real world, or have to restart the game from the beginning. While avoiding the lasers from the Game Child, Darwin suggests using their potion, but Gumball ends up throwing it at Game Child instead. Anais suggests using the phone to summon allies in battle. Gumball activates it, allowing him to summon Sarah, Hector, Banana Joe, Carrie, Granny Jojo, Nicole, and Richard to defeat the Game Child once and for all. After one last victory pose, the game's credits start. Anais and Darwin are glad it's over, but Gumball's dissatisfied that he only achieved 89% completion. When it offers Gumball to start a new game, Anais and Darwin try to stop him as he presses "Yes" on the screen.
The fourth wall is broken a couple times in this episode:
Gumball smacks Leslie's face with a dialogue box.
When Penny falls over, the dialogue box does too.
The credits for Inverted Paradox list Ben Bocquelet as the director.
When Gumball, Anais, and Darwin momentarily go into a fully pixelated town, the town looks similar to the one used in the promotional video for the Japanese ending theme song for The Amazing World of Gumball.
In the dialogue sequence where Gumball, Darwin, and Anais grow "anime hair," Gumball and Darwin's resemble the haircuts of Cloud and Sephiroth, while Anais's resemble the haircut of Rizelea from Trinity Universe.
The episode's theme and the battle music of Inverted Paradox: The Enemy Within is extremely similar to the battle theme, "Let the Battles Begin!"
The victory fanfare of the Final Fantasy series is also referenced.
Banana Joe's pose is a reference to the Cactuar creature, and the attack "Thousand Blows" is the Cactuar's signature move, "1000 Needles."
The final attack when Gumball uses the phone to summon all his friends is a parody of Ultimate End, the strongest Summon in Final Fantasy VII. Both attacks involve a myriad of characters ganging up on an enemy.
"Chainor" is a misspelling of China, spoofing on Engrish, or the accidental misphrasing or misspelling of words when translated into English.
Darwin saying he forgot Gumball's name is a reference to RPGs where the player has to type in the protagonist's name.
Anais defeating the leaf monster with a fire attack is a reference to type effectiveness in games such as Pokémon and Mega Man Battle Network.