

The N-Team is playing a shooting game, while Mother Brain, King Hippo, and Eggplant Wizard watch on Metroid. The game ends, and they're about to go back to the Palace, when the Warp Wagon is pulled down to the world of Tetris by a powerful force. Mother Brain sends Hippo and Eggy to Tetris to find the source of that power, so she can get it for herself. It turns out that on Tetris, everything is square- and cubed-shaped. The N-Team is greeted by Mayor Squaresly, who declares today ""Her Royal Roundness Day"". The people of Tetris love holidays! The mayor takes the N-Team to CUBIES, ""home of the best square meal in town"", where they meet Lyle, Lana's clumsy older brother. The two siblings hadn't seen each other for two years. Lyle's been on Tetris all this time, and doesn't even know that his father is missing. He's a Keeper of the Sacred Square (the powerful force that pulled down the Warp Wagon). According to legend, the Square is so powerful that it built the entire world of Tetris. Ly
King Charles is about to come home through a warp zone that only opens every 1000 video years. But he decides to send a supercomputer called Game Boy in his place. Game Boy turns out to be nothing but trouble for the N-Team. Mother Brain gets Game Boy, and Dr. Wily turns him into Game Brain. When the N Team comes to Metroid to rescue Game Boy, Game Brain sends monsters after them. Duke comes to the rescue, pulling the cords out of Game Boy with his teeth! The monsters disappear. Back at the Palace, the gang officially welcomes Game Boy to the N-Team.
The N-Team is invited to Kongoland by Prince Plenty. Dr. Wily invents a brain swapper so Mother Brain can get a body. She chooses Princess Lana as the donor. However, when they go to Kongoland, Donkey Kong kidnaps Mother Brain and Game Boy. The brain swapper is accidentally attached and activated. Donkey Kong gets Game Boy's body, Game Boy gets Mother Brain's body, and Mother Brain get Donkey Kong's body. Simon and Kevin go to find ""Gape Boy"", Kid Icarus and Mega Man search for Game Boy's ""brain-in-a-bottle"", and Lana decides to give ""Mother Kong"" a makeover. Donkey Kong's family elect Simon their new leader! Everyone's brain is swapped back to the right place, and the Kong family carries Simon off.