Stafy (A.K.A. Stafi, Starfy, and Starfi) is an athletic starfish, capable of quickly traveling in or out of water. With help from his younger sister Stapy, and advice from his clam friend Kyorosuke, Stafy embarks on yet another quest to defeat the evil Oogura.
At the beginning of World 8, Wario warps in à la Wario Land 4, and meets Stafy at the "Undersea Ruins" entrance. Stafy uses Wario (and his transformations) to progress through World 8, and Wario finds treasure in the process. At the end of each level, Wario rewards Stafy with various "Goods" which become part of Stafy's "Dress-up Doll" accessories collection.
In World 8-1, Wario drops in, and his trademark laughter is heard. Inside the ruins, two doors are blocked by huge "Fire Blocks." After hitting a statue to set Wario aflame, Stafy must hit the platforms below Fire Wario to bump him over the stones so he can clear the block at the end.
In World 8-2, Stafy must guide Wario to the bottom of a water-filled chamber. Wario will often get trapped in a bubble and start to float upwards, so Stafy must repeatedly pop Bubble Wario to reach the bottom of water. In another room, the goal is to reach the top, so Stafy must guide Bubble Wario around spiked platforms.
In World 8-3, Stafy jumps on a Frog Switch, which triggers an auto-scrolling level where only low spots in the floor can save Stafy from being smashed by a rising and falling spiked ceiling.
In World 8-4, an evil green clam steals Wario's gems, so Stafy and Wario go through four rooms to find him. In one room, Stafy has to ride Balloon Wario to the top, guiding him around spiked platforms. In other rooms, Stafy deals with Fire Wario and Bubble Wario (popping) again.