This level introduces Mega Urchins and is mostly submerged in water.
This level begins on land, near a platform above the water with two ? Blocks above it. The player must then travel through a section of water, where Urchins, Cheep Cheeps, Mega Cheep-Cheeps, and a Piranha Plant are encountered. A piece of land with a Koopa Troopa, a Red Ring, and two ? Blocks are in the section. Afterward, two currents coming out of Warp Pipes are found, along with a wall that leads underwater. A group of Spiny Cheep-Cheeps follows along with a platform with a ? Block containing a Starman. The midway point then follows. The player must then go into the water, where more Urchins and Warp Pipe currents are located. A Roulette Block is hidden in the wall above. A section with Mega Urchins follows, with Koopa Paratroopas flying above. After a Big Urchin with two Urchins, a structure made of Brick Blocks and ? Blocks is encountered. Underneath the last Big Urchin, there is a Warp Pipe leading to an area with three Clampies. After a section with more Urchins and currents, a Warp Pipe leading to an area with a Koopa Paratroopa and the flagpole is found.
- Star Coin 1: Freeze the Pirahna underwater with the Penguin Suit, then jump on the frozen Pirahna to get the first Star Coin. This is located near the beginning of the course.
- Star Coin 2: Freeze the Urchin underwater with the Penguin Suit, then jump on the frozen Urchin to get the first Star Coin. You've got to hurry before it unfreezes! This is located slightly after the midway point.
- Star Coin 3: Belly slide on the water that has Urchins and pipes underneath. Then jump on the ledge. There is a pipe, but don't enter it yet! There is the third Star Coin waiting for you.