Gameplay sum up: You start you out in Delfino Plaza, the island's biggest city, which serves as the game's hub, and is roughly three times bigger than the hub presented in Super Mario 64. This hub has portals in the form of statues on the side of building, and in other strange places that lead to the many levels. When you enter a level, a screen pops up showing 8 Shines, which represents each of the level's 8 objectives and the game's 120 total Shines. You will then enter the level, complete the objective (each varies to the extreme), and earn the Shine, which will start to unlock more doors to more portals and levels, and ultimately lead you to the showdown with Bowser. Each level also has two hidden Shines, and one Shine for collecting 100 coins in each level.

New to this game is Mario's sidekick, FLUDD, which is a talking water tank that is strapped to Mario like a backpack and serves as a tool to clean up the gooey graffiti found all over the city and levels. You start out with the ability to spray from FLUDD like a hose and float in the air with the FLUDD's hover attachment. And later in, you'll gain the Rocket Nozzle that shoots Mario straight into the air and the Turbo Nozzle, which propels him at high speed on land and makes him like a mini power-boat on the water. The FLUDD will eventually run dry, and to refill it, you will enter water and press the right-trigger. Lastly, Yoshi makes a surprise return, and is accessible a quarter way through. And to ride him, you must feed him his favorite fruit for him to hatch. He (depending on a fed fruit) also shoots fruit juice from his mouth, which is used to dissolve barrier puzzles around the city—but don't let him touch water; he'll disappear.