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The Rumpus Room (Play Room in the British English version) is a room inside of the Haunted Towers in Luigi's Mansion: Dark Moon. The Rumpus Room can be accessed by walking up the stalk inside of the Plant Nursery or by taking the north door inside of the Family Room. The Rumpus Room is a fairly large room. On the left side, there is a giant doll that turns its head to face Luigi. There are several smaller dolls on the ground and a shelf. There are a few alphabet blocks and five jack-in-the-boxes. By the north wall is a dollhouse that Luigi can peer into to see a mirror image of this room and a jack-in-the-box shaking. On the area to the right, there is a rocking horse, a vanity, and a few more dolls on shelves. There is a missing shelf here that can revealed with the Dark-Light Device, but it only contains a towel.
In B-4: Pool Party, Luigi needs to travel through the Rumpus Room in order to reach the Rooftop Pool. However, there are ghosts in this room that will only reveal themselves if Luigi looks through the dollhouse. By looking through the dollhouse, a jack-in-the-box will start to shake. Inspecting this specific box causes five Greenies to pop out. After defeating the ghost, pulling out the six curtains and towel in this room causes twenty bills to fall from the ceiling. In B-Bonus: Hostile Intrusion, the Rumpus room might be one of the rooms that is infested with ghosts.
Starting on B-4: Pool Party, if Luigi turns the doll's head counterclockwise, its head will pop off and reveal an emerald.