The gameplay remains very close to that superb blueprint introduced in Mario 64, with a similar moveset, familiar enemy encounters, and generally comparable platforming elements throughout. However, the gameplay is a major departure from said formula in one aspect: the introduction of Mario’s hydro-pumping backpack, F.L.U.D.D.
Mario utilizes F.L.U.D.D. throughout a majority of the game, and can apply it to a wide variety of different uses – most notably, the ability to Squirt objects and enemies that are due for a good rinse, as well as the ability to hover, which allows for a safe recovery from dangerous falls, and provides the aptitude to reach previously inaccessible areas.
Super Mario Sunshine has gameplay similar to previous Super Mario game, Super Mario 64. As with every Mario game, however, it adds new gameplay aspects and features. Likely the most important upgrade is the addition of F.L.U.D.D. (Flash Liquidizing Ultra Dousing Device). F.L.U.D.D. is a pack that Mario wears that can either spray water or use water power to have Mario hover. Other nozzles can be unlocked later: the Rocket Nozzle and the Turbo Nozzle. The Rocket Nozzle can shoot Mario several hundred feet into the air. The Turbo Nozzle can allow Mario to run at incredible speeds, even allowing him to run on water and break through thing s like doors.
Mario can also enlist the aid of Yoshi. When riding Yoshi, he can eat enemies, fruit, and even birds. Some of the birds grant a Shine Sprite upon being eaten, while others give coins. After eating fruit, Yoshi can spit juice from the fruit. This juice can dissolve large orange blocks, which are obstacles blocking certain secret areas. The juice can also turn enemies into platforms. Based on the type of fruit, the color and effect of the juice are different. Yoshi can die in two ways that Mario can't: without eating fruit, Yoshi will die, and when Yoshi touches the water, he dies.
The primary goal of Super Mario Sunshine is to collect Shine Sprites. These are in a variety of smaller levels, from the hub world of Delfino Plaza. Each Shine Sprite can be acquired by doing a specific task in the level. Every level has eight such tasks to be completed. After collecting a large enough amount of Shine Sprites, a new level is unlocked, Mario gets a new ability, or an event related to the plot. Shine Sprites can be collected in other ways, such as gathering enough blue coins (scattered around Isle Delfino) or eating certain birds. Not all Shine Sprites need to be acquired in order to gain access to the final level; only Shadow Mario related events.
The game opens with Mario, Princess Peach, and several of the Princess' royal entourage aboard a private plane, en route to Isle Delfino, a destination that everyone believes will be a tranquil escape from the every day grind of kidnappings, fire-breathing behemoths, and general mayhem that makes the Mushroom Kingdom such an unproductive working environment. However, the holiday is brought to an abrupt halt as soon as the vacationing group touches down on the runway, when they discover a prominent work of graffiti that bears an apparent resemblance to the mustachioed plumber. Mario travels to the other end of the runway to seek help in clearing the obstruction, and is introduced to a talking, water-pumping backpack, nicknamed F.L.U.D.D.
With the help of his newfound semi-sidekick, Mario is able to clean up the runway of all graffiti and restore it to its original state. However, no sooner is this act of goodwill completed than two of Isle Delfino's finest arrive on the scene to bring Mario under arrest for evidently fouling up several other areas of the island. After a fairly unfair trial, Mario is ultimately sentenced to clean the entire island of all of the pollution that blemishes it before he will be permitted to leave. Doing so will quite literally brighten up the place, as a good many of the island's " Shine Sprites" have gone missing due to the rampant vandalism. These "Shine Sprites" traditionally gather at the "Shine Gate" in the center of town, and are the source of the pleasant rays that illuminate the island paradise; but, the malicious work of the real vandal has essentially scared them all away, leaving the island covered, in large part, by a persistent shadow.
By traversing the many areas of Isle Delfino, and working to undo the true culprit's defacement and overall trouble-making, Mario will collect and return the "Shine Sprites" to their rightful place and restore the island to its normal, immaculate state.