Dancing Blocks, Poison Swamp
From the Super Mario Wiki
Dancing Blocks, Poison Swamp, or Soda Jungle-2, is the second course of Soda Jungle in New Super Luigi U. It is unlocked by completing Giant Swing-Along, and its own completion will unlock Stone-Snake Tower.
The level starts in a jungle, near a curved Brick Block structure below a ? Block. Two vines that protract and retract are found, followed by triangular Brick Block formations that occasionally drop into the poison. Some Koopa Paratroopas are found, along with two ? Blocks. Another vine is found after the Brick Block structures, followed by a platform with a Goomba and a Koopa Troopa on it. Two more vines are found, followed by curved Brick Blocks structures that enter the poison. More Koopa Paratroopas are found flying above the Brick Blocks. The player then reaches the Goal Pole.
After the set of triangular brick formations, the last one is breakable and has a ? Block on the bottom. Hitting this by Ground Pounding makes a ? Switch drop from the sky. Upon being pressed, it reveals a path to a Warp Pipe which takes the player to the goal pole. The secret exit leads to Sumo Bro Bridge and Wiggler Floodlands.
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