The game revolves around 16 minigames. In single player, the player is only allowed to play as Garfield while the opposing team (mice or space lasagna) are the AI. In multiplayer, the players may choose to either be Garfield or the opposing team. The game also includes a story mode where the player can unlock all the minigames and hats, and a minigame mode, where the player can choose any minigame they unlocked. In each game, either Garfield tries to stop the opposing team, or the opposing team try to keep Garfield from thwarting their plans. Every minigame supports either the Wii Balance Board or the Wii Motion Plus.
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While Garfield is sleeping, the Space Lasagna are planning their return to Earth to take revenge on Garfield for stopping their plan on the episode "Pasta Wars". They discover that Garfield is friendly with the mice, and decide to take control of them, and make the mice wreak havoc around the city while the Space Lasagna go about with their plan. Later that day, after the Space Lasagna start their plan, Garfield finds Squeek hiding. Squeek then tells Garfield about how the Space Lasagna took control of his family, and Garfield decides to save Squeak's family, and stop the Space Lasagna from invading their planet.
|The section above contains spoilers! Content within that section may reveal significant parts of a game(s) story.|