Larry's Torpedo Castle, or Sparkling Waters-Castle, is the castle of Sparkling Waters in New Super Mario Bros. U. This course is unlocked via completion of Dragoneel's Undersea Grotto and its own completion unlocks the path to The Mighty Cannonship.
This castle contains moving fences, Burners, and Torpedo Teds. In the first room of the stage, the player has to climb moving fences and dodge the fire of the Burners. Next, the player goes in to a Warp Pipe which leads to a room filled with water and Torpedo Bases. After dodging some Torpedo Teds, the player reaches the Checkpoint. This is followed by a Warp Pipe that leads to an area with coins and Burners. As the player goes back to the underwater area, there is a Red Ring. Next, the player enters a Warp Pipe which leads to a short room with Burners and moving fences. After avoiding the fire of the Burners, the boss door is found. A cannon is found through the boss door, and leads to Larry Koopa. Waterspoutss are found during the battle with Larry, and he is defeated after being hit three times.
- Star Coin 1: The first Star Coin can be accessed by jumping on top of the ? Blocks and wall jumping to the Star Coin while avoiding the Burners.
- Star Coin 2: The player must swim under a platform where Torpedo Teds are shot without getting hit in order to collect the second Star Coin.
- Star Coin 3: The third Star Coin is hidden at the top of the screen. The player must climb the moving fences.