SpongeBob's Truth or Square follows the story of SpongeBob as he loses his recipe for the Krabby Patty, entrusted by Mr. Krabs. With the help of Plankton and his memory machine, which uses the happiest moments of his life to aid in the search, SpongeBob must navigate through various locations in Bikini Bottom to recover the lost recipe.
The gameplay in SpongeBob's Truth or Square involves defeating enemies by transforming SpongeBob into different forms, such as a sledgehammer or an explosive cannon. You can also play as WaterBob to splash enemies, adding a unique twist to the classic platformer genre.
A key feature of the game is its co-operative multiplayer mode, allowing two players to team up and play together over a split screen.