Poltergeist

Poltergeist is a sub boss in Luigi's Mansion: Dark Moon. While Luigi explores the Gloomy Manor, E.Gadd, insists Luigi to capture this ghost for study purposes. When Luigi tries to head to the 2nd floor where the Library is located, the Poltergeist makes the stairs into a slide causing Luigi to look for the key to the Library before approaching. Just as he does approach it with the key, the Poltergeist flips the stairs and traps Luigi below with several Greenies and Slammers. Upon capturing them, Luigi can proceed to the Library where he battles the Poltergeist. The Poltergeist can also be encountered as a boss on the ScareScraper.

Abilities
The Poltergeist has the power to move objects with telekenisis. When Luigi fights the Poltergeist, it throws books at Luigi while Luigi searches for it. It can also throw books at Luigi while its being sucked into the Poltergust 5000 to get away. Additionally, it can create up to two clones of itself that Luigi will need to dispose of before he can suck up the main ghost. It also plays the piano during the entire battle.