Guppy and the Underground Lake
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The player must make their way down to the bottom of the underwater cave. There, they will find Guppy waiting on a star-shaped rock, and approaching him will have him challenge the player to swim through eight rings. All eight rings are placed either within a group of enemies or an obstacle. The player can use Green Shells to move through all the rings before they disappear, and failing to move through a ring will cause the player to fail the challenge. Swimming through all eight rings before they disappear will have Guppy give up a Power Star.
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