Nikki, Lindsey, & Ginny

Nikki, Lindsey & Ginny are a trio of magician ghosts who collectively serve as the twelfth boss in Luigi's Mansion 3. They haunt the Twisted Suites and guard the twelfth floor's elevator button. It is not specified in the game which character the names apply to.

Appearance
Nikki, Lindsey, and Ginny are purple ghosts with blonde hair, gleaming white eyes, and long eyelashes. They wear dark purple tuxedos, capes, top hats, and white gloves. One of them has a single pony tail, another has two long pony tails, and the third one has two short pony tails.

The trio are first seen immediately after Luigi exits the elevator, to which they taunt him before moving out of the room. They appear in various rooms and continue to scare Luigi around the floor until he makes it to the Wardrobe, where they use their magic to scramble the doors, causing them to lead to different rooms from the ones intended. When Luigi gets back to the Stage, the trio appear and give showman poses before ducking into their hats and attacking Luigi, and then spin around him before laughing as they disappear. They teleport Luigi into another dimension via curtains, beginning the boss battle.

Battle
The three ghosts, after posing, will duck into their hats, launch cards at Luigi, then orbit him and while continuing to launch cards before attempting to attack at close range. When the trio is close enough, Luigi must burst the area to immobilize them, then pull out one of the ghosts to suck her into the Poltergust G-00. If Luigi misses a hat, it will attack him with an unavoidable card, causing him to trip and let all the immobilized hats escape, which will then begin to orbit Luigi again. After one ghost is sucked in, the remaining members of the trio will repeat their attack pattern, except that they will place another hat with a bomb inside that damages Luigi if he attempts to pull it out later. If Luigi guesses the wrong hat, he will take 20 damage from the bomb that he pulls, the remaining ghosts will laugh at Luigi and restart their attack. Additionally, once Luigi captures the second ghost, the remaining one will summon two decoy hats, and will even momentarily turn off the lights while orbiting Luigi to throw off the player's attention to the correct hat.

All three ghosts have the same "defeated" animation: they struggle furiously to escape the grasp of the Poltergust G-00, while the last ghost struggles even more, but they ultimately fail and are sucked in.

Trivia

 * Their English, French, European Spanish, and Dutch initials when put together ("NLG") reference the developer of the game, Next Level Games.