It begins with Mario in front of a pool of water infested with Urchins, an orange platform and a pipe leading underwater. First, two Urchins can be seen next to a wall which moves after a set amount of time passes. Two ? Blocks follow, one of them containing a Fire Flower. Urchins then begin to bounce and roll down on slopes on the floor. Several walls will then move down halfway, covering several coins. A Deep Cheep appears, followed by more Urchins. Several more Deep Cheeps and Urchins will then appear, followed by the checkpoint. A Roulette Block can then be found, followed by two Urchins and a Red Ring. More Urchins fall and the floor moves up slightly at certain spots. More Urchins and Deep Cheeps appear. Parts of the floor and ceiling can be found enclosing Urchins which will come out when the floor or ceiling opens up. After that area, Mario needs to navigate through an area full of Urchins. At the end is the exit pipe out of the water. Several blocks in the area can help Mario reach the top of the flagpole, which is a short distance away.
- Star Coin 1: Just before the checkpoint. When the player sees that the ceiling closes down halfway, Mario will need to move as far right of the screen as possible while keeping to the bottom of the level. Mario needs to avoid the Deep Cheep and Urchin which appears after that. When the player sees a gap, Mario needs to quickly drop down the gap and move right before the floor moves up to get the Star Coin.
- Star Coin 2: The Star Coin can be found hidden behind an Urchin which is enclosed in the ceiling after the checkpoint. It can be obtained when the ceiling opens and the Urchin falls.
- Star Coin 3: At the very beginning of the area infested with Urchins (immediately after the area with the second Star Coin), the player should see a green pipe above the first Urchin at the top. Mario needs to enter the pipe. Upon entering the pipe, Mario needs to quickly swim to the top of the area where the Star Coin is located while avoiding Deep Cheeps and large Deep Cheeps before the walls adjacent to the Star Coin closes up.