Polterkitty

Polterkitty is Hellen Gravely's ghostly cat which appears as a recurring boss in Luigi's Mansion 3. Her behavior acts similary to Polterpup from Luigi's Mansion: Dark Moon.

History
Polterkitty is first seen in a cutscene after Luigi rescues Toad, where she is seen on Hellen Gravely's lap while she watches Luigi's progress. After Luigi retrieves an elevator button from Morty in the Paranormal Productions, Polterkitty steals the elevator button as soon as it is placed in the elevator. Luigi must use his Dark-Light Device to reveal Polterkitty's invisible footprints which lead to her location. After Luigi flashes Polterkitty with his Strobulb, she will transform into a monstrous panther-like form. Whenever Polterkitty takes this form, Luigi must face away from her while she sneaks behind him, then wait until right she is about to strike to flash her with the Strobulb, then vacuum her with the Poltergust G-00. Doing this the first time only pulls off one of Polterkitty's tails, and she then flees to the Garden Suites, where Luigi chases her to. After yanking two more of her tails, Polterkitty gives up the elevator button and returns to Hellen Gravely.

Polterkitty reappears after Luigi retrieves another elevator button from Johnny Deepend in the Fitness Center, once again stealing the elevator button after it is placed in the elevator. This time, Polterpup helps Luigi track down Polterkitty, and together they hunt her down. Polterkitty regrew the tails she had lost previously. After she loses one of them, she flees to the Spectral Catch, then after losing the second she flees to the Twisted Suites. When Polterkitty is encountered the third time, as soon as Luigi turns to face her right before she strikes, she quickly goes right behind him, prompting Luigi to quickly turn as well. Polterkitty is then completely sucked into the Poltergust G-00, and Luigi retrieves the elevator button she stole.

In the Gallery, Polterkitty shares the same containment jar as Hellen Gravely, although she will not appear until Hellen is captured.