The player starts out on land with block formations above. A Warp Pipe leads to the main level, which takes place underwater. Landing underwater, Mario will have to avoid Cheep Cheeps while swimming through the level, or use fireballs to kill them if he is currently in the Fire Mario form. After several amounts of Cheep Cheeps and coins, the player can find the first Star Coin in plain sight. A Red Ring is right after, in which collecting all eight red coins will give the player a power-up, depending on their current state. After the first whirlpool the player has to avoid getting sucked into, is the checkpoint. A Question Block shortly after has a Star, in which two more can be obtained if the player swims fast enough. After another whirlpool, the player can find a yellow Warp Pipe, where the second Star Coin is located. After two more whirlpools the player must avoid, the player can find another whirlpool, but this time it is surrounded by bricks. The player get can sucked down to find the third Star Coin. After a few Big Deep Cheeps, the player can find a green Warp Pipe that will take them to the end of the level and the flagpole.
- Star Coin 1: The first Star Coin can be found in plain sight, just before the Red Ring.
- Star Coin 2: The second Star Coin is located in a hidden section, accessed by a yellow Warp Pipe just past the first whirlpool after the checkpoint.
- Star Coin 3: The third Star Coin is located in a hidden section, accessed by sinking into a whirlpool surrounded by bricks.
|Cheep Cheep||Random spawner|
|Deep Cheep||Random spawner|
|Big Deep Cheep||2|