The Walls Have Eyes
From the Super Mario Wiki, the Mario encyclopedia
The Walls Have Eyes, or Layer-Cake Desert-4, is the fourth level in the second world of New Super Luigi U, Layer-Cake Desert. It can be accessed upon completion of Wind-Up Tower. Clearing the level's main exit gives access to Spinning Sandstones. A secret exit leads to Slippery Rope Ladders. The name of this level is a pun on The Hills Have Eyes, which is the name for various works, or from the Japanese proverb: "Walls have ears, and the shōji (Japanese windows made of paper) have eyes."
Luigi starts the level in front of a Stone-Eye statue. Going to the right, there is a tunnel where an endless number of Stone-Eyes slide to the left. Exiting the tunnel, there are three Stone-Eyes forming a bridge, and Waddlewings are found above them. A Mini Warp Pipe leads to an area with a Stone-Eye, coins, and 1-Up Mushrooms. Next, Stone-Eyes that act as pendulous statues, and Big Piranha Plants on Warp Pipes are found in between them. A section of Stone-Eyes that move up and down is next, and they are followed by two more Big Piranha Plants. Three more Stone-Eyes act as platforms leading to the Goal Pole.
Luigi (who must be at least Super Luigi) must Ground Pound the piece of land between the Waddlewing section and a Mini Warp Pipe. He will break some Brick Blocks and reveal a hidden Pipe Cannon that blasts him to the secret Goal Pole. The secret exit leads to Slippery Rope Ladders.
The player can find Super Luigi's crouching 8-bit sprite in the underground bonus room that is reached entering a mini-sized Warp Pipe. However, there are no Mini Mushrooms in the level, and one must be obtained from another level.
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