Getting Superstar rank (20000 points) in every level unlocks an additional Star (only after finishing Champion's Road).
Getting at least an A rank (17500 points) on every level in a world unlocks a Star in that world's Toad House. Now Mario must recover the Grand Ztar before Bowser can use it in his latest evil plan. Bowser barges into the chamber and scares the Toad away, claiming the Grand Ztar for himself. Princess Peach's birthday has arrived, and most of the Toads are at her castle eating cake, except for one guarding the Grand Ztar.
