In this level, there are Big Piranha Plants, Stalking Piranha Plants, and Buzzy Beetles. The course is a network of Warp Pipes with raising and lowering platforms which the Big Piranha Plants are on top of. Some switches raise and lower the level of the water.
- Star Coin 1: The first Star Coin is floating above the third Big Piranha Plant. Mario and co. must kill the Big Piranha Plant and then use the platform to rise up to it, or wall kick.
- Star Coin 2: The second Star Coin is next to the fourth Big Piranha Plant. Mario and co. should again kill the Big Piranha Plant to make the Star Coin accessible.
- Star Coin 3: At least a Super Mushroom is required for this one. Shortly after the Checkpoint Flag, there are three Big Piranha Plants with one guarding a row of Brick Blocks. Mario and co. must break through any but all of the Brick Blocks and wall kick to the area atop them to be brought to the secret area with the third Star Coin.