"Super Mario Sunshine" introduces several elements which were carried over to subsequent "Mario" games. Many of the characters introduced in this game have been staples in the series ever since: Petey Piranha, Cataquacks, and Bowser Jr., who has been one of Mario's archrivals ever since this initial encounter. Many of the bosses from this game and "Luigi's Mansion" appear in multiple "Mario" spin-offs that followed on the GameCube, such as the unlockable Petey Piranha and King Boo in ' and the four unlockable characters in '.