Mario, Luigi and Yoshi return to the Dim Caverns and find 6 eggs by the cave-in. Just then the eggs hatch and the heroes realize that the spiders inside the eggs are Black Arachnia's children. The children find katanas by the wall of the cave and pick them up. They already know how to use them, despite being just hatched. The cut through all the rocks then leap out of the cavern. But, they get captured by a koopa driving the Koopa Cruiser. The heroes decide to rescue them and jump on to the Koopa Cruiser. The koopa driving the Koopa Cruiser's name is Shadow Troopa and he battles the heroes. Shadow Troopa falls off the Koopa Cruiser, but is rescued by one of his partners. The heroes release Black Arachnia's children. The heroes jump off the Koopa Cruiser and land back in the dim caverns and find a bag with 2000 coins in it.