Sparkling Waters

Sparkling Waters is the tropical world in New Super Mario Bros. U. Players can reach it by moving south from the end of Layer Cake Desert. Sparkling Waters lies east of Acorn Plains, south-east from Layer-Cake Desert, south from Frosted Glacier, and west from Soda Jungle. Sparkling Waters is in an ocean filled with multiple islands and having bubbling water geysers, which is quite similar to World 4 from New Super Mario Bros Wii as that tropical world also had multiple islands. The world's name is possibly a reference to carbonated water. There are 9 levels in this world, consisting of 6 normal levels, a secret level, the Tower level and the Castle level. The boss of this world is Larry Koopa.

Levels

 * Sparkling Waters-1: Waterspout Beach: It features Huckit Crabs and water geysers.
 * Sparkling Waters-2: Tropical Refresher: An underwater course where many pipes are found.
 * : Giant Skewer Tower: A tower level holding Spike Pillars.
 * : Haunted Shipwreck: The ruins of a ship infested with Boos.
 * Sparkling Waters-3: Above the Cheep Cheep Sea: A course with Yoshi and giant Water Geysers.
 * Sparkling Waters-4: Urchin Shoals: The fourth level of Sparkling Waters includes Urchins and water geysers.
 * Sparkling Waters-5: Dragoneel's Undersea Grotto: Introduces Dragoneel, who follows and attacks the players.
 * : Larry's Torpedo Castle: Contains climbing fences and Torpedo Teds.
 * Sparkling Waters-Leaf: Skyward Stalk: A course which consists of climbing a giant beanstalk.

Challenge Mode original courses

 * Bubble Up