Make Wiggler Squirm
From the Super Mario Wiki
To get to Wiggler, the player has to first reach the top of Tiny Island. At the top is a small hole underwater, and Ground Pounding it will drain the water. Once that is done, the player needs to climb down the mountain to the Shrinker Pipe at the base and jump in, bringing the player to Huge Island. Afterward, the player has to climb back up the mountain and fall into the now exposed hole. If the water is not drained on Tiny Island, the player cannot enter the hole.
Once inside Wiggler's cave, Wiggler will begin a dialogue complaining about the water drained into his home. Once the dialogue ends, the battle with Wiggler will begin. To defeat Wiggler, the player needs to jump on him a total of three times. After each hit, Wiggler will complain and move faster, beginning the next phase of the fight. On the third phase, Wiggler will begin to charge at the player, and he will turn red in the DS version, which is a trait other Wigglers have. If the Wiggler rams into the player character or the player runs into the Wiggler's body, they will take damage. In the DS version, only Wiggler's head will deal damage. After three hits, the Wiggler will be defeated and shrink, dropping the Power Star and falling into the chasm below.
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