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The Skip Slope (Icy Slope in the PAL-version) is a room inside of the Secret Mine in Luigi's Mansion: Dark Moon. The Skip Slope is accessed by taking the left door inside of the Crossroads. The Skip Slope is essentially a long slide. There are two forks in the room that leads to different areas of the slide. On the bottom, there is an E-Gate to get back up to the top of the slope as well as a door covered by a propeller-operated mechanism nearby. A large, rotating gear is found near the second fork. Pulling the cord on the bottom drops a bucket with three gold mice under it. The door on the top right leads back to the Crossroads and the door on the Floor B2 leads into the Smuggler's Hideout.
During D-2: Hit Rock Bottom, Luigi needs to slide down the Skip Slope to reach the basement area. However, the door leading to the Smuggler's Hideout is locked. If Luigi takes the fork on the right side, he can get the key that is needed to unlock the door. In D-3: Across the Chasm, Luigi has to slide down the Skip Slope one more time in order to find the Strong Greenie that has hidden in the Smuggler's Hideout. There are numerous spiders hanging on their webs during the slide and three gold spiders are found on the right fork.
Starting on D-2: Hit Rock Bottom and most missions after, near the end of the slope, the road has a fork to the left. Luigi must use the blow function on his Poltergust 5000 to slow down and time it so that he goes between a gap in the gear blocking the fork. If Luigi manages to go through the gear, there is a sapphire in the middle of the slope that Luigi can grab.