This level is an over water level mainly themed with barrels and introducing Skeeters.
When Mario first spawns in, he can make a few jumps over to a barrel with a Question Block and a Skeeter. You can also go underwater and collect coins with questions blocks having more coins. If you keep swimming, you'll find a Red Ring or if you're on the surface, you can encounter another Skeeter. If you go for the red ring, the Red Coins will spawn around on the island above, which contains a red Koopa Troopa. However, you can also completely swim under the island and collect a few more Coins, which are underneath 2 more skeeters trapped in blocks. You can also jump across the skeeters onto the next island because you can't swim under this one. This island will have more coins and 2 more red Koopa Troopas. Next, there will be a couple of skeeters with moving platforms for Mario to jump on, and coins scattered above and under the water. The next island after that will have another Red Koopa and some more coins. Then there will be some Skeeters and a red switch underwater. If you press it, red blocks will appear and create platforms for Mario to jump to the next island with the checkpoint. Next to the checkpoint is a green Koopa Troopa and some Brick Blocks which can be broken with the koopa shell. There is also some question blocks with one containing a power up. Next, is the first Star Coin, trapped in a bunch of brown blocks (except from the bottom). You can use the skeeter there to break the blocks and allow you to get it. After that, is a few more jumps with more red Koopa Troopas and a question block underwater. This question block will have a Mini Mushroom that Mario can use later on. Then, there will be more jumps above the water alternating between ground and barrels. It will also be inhabited with Skeeters and red koopas. The secondStar Coin will require you to jump off a koopa or a skeeter but if you are Mini Mario, it can be done with ease. Go in the pipe to enter the second area of the level. When you enter, jump across a moving platform over to a Warp Pipe with the final Star Coin. You will need to be Mini Mario to run across the water then jump to collect the coin. Once you have it, go up the pipe on the other side and back into the main level. Now jump across more moving platforms past some green Koopa Paratroopas and some Skeeters into the Warp Pipe. Once you're there, use some donut blocks to slide down the flagpole.
- Star Coin 1: After the checkpoint, Mario can find a lone Skeeter. The Star Coin is protected by brown blocks and requires the Skeeter's bombs to penetrate it, or the player can just swim directly under the blocks and then up to the coin.
- Star Coin 2: After the first Star Coin, the second Star Coin is on midair and requires Mario to jump off a Koopa Troopa or Skeeter to get it. He can also collect it by jumping off of the barrels if he times his jumps correctly.
- Star Coin 3: After taking the Warp Pipe to the second area, the player should become Mini Mario and take the regular Warp Pipe, not the small one. They should run across the water and jump to get the final Star Coin. The coin can also be obtained by using a Mega Mushroom.