Possessor Ghosts

A Possessor Ghost is a special ghost found only in Luigi's Mansion 2, that has the power to possess anything they see. There are 5 of these ghosts total in the game, one in each mansion. They are also the main boss battle ghosts in Story Mode. They have infinite healthpoints and three layers of skin, so players need to charge up their Poltergust 5000 to rip their skins off one by one.

They sport unrivaled speed and strength and they are the only ghosts that are not controlled by King Boo throughout the story.

Battles
Defeating each possessor gets Luigi a Dark Moon piece.
 * 1) The first Possessor, the Grouchy Possessor, found in the Gloomy Manor Mansion, possesses a giant spider. Luigi has to blind the spider with his flashlight. While it's distracted, Luigi must then use his Poltergust 5000 to pull a ball of webbing on the spider's web on the wall to a fire while avoiding blobs of purple goo the spider spits out. The web burns down, causing the spider to fall to the ground, and the Possessor reveales itself. Out of their possessing objects, all the Possessors have one attack: covering themselves with an invincible shield, and charging at Luigi, after charging into something, they stop, leaving them vulnerable to being sucked up, (see "facts" for more info). After a skin is removed, the Possessor goes back into the spider. Luigi must repeat the process two more times, each time, the spider crashes through the wall revealing a farther away web.
 * 2) The second Possessor is the Harsh Possessor, found in the forest-theamed Haunted Towers, where he turns a staircase into a monster.  Luigi must simply avoid the stair's attacks untill it jumps high in the air, and slams into the ground, revealing a lamp cord, Luigi must suck the staircase's "tounge" making the Possessor pop out, in the second phase, the stairs can shoot fireballs.
 * 3) In the Old Clockworks, the Overset Possessor possesses the giant clock face on the clockwork's roof, the clock spits out enemies depending on the time the clock shows. After each hour, the minute hand glows red and spins to the next hour, if Luigi touches the spining hand, he will take damage. Every 4th hour, the Possessor pops out.
 * 4) The Shrewd Possessor is in the frosty Secret Mine, and he posseses a frozen lake, turning it into a monster-like face. Unlike the other battles, in this one Luigi is on a bomb shooting sled. The ice monster will cover itself with a sheet of ice, Luigi must shoot bombs at the ice, breaking it, he must then  shoot a bomb into the creature's mouth, blowing it up, revealing the possessor, each phase, the ice sheet needs more hits to break.
 * 5) The final Possessor faced is the Tough Possessor he is fought in the museum-theamed Treacherous Mansion, after Luigi is sucked through a portal into a Paranormal Dimension. The Possessor splits into two and each possesses a suit of armor which follow Luigi and try to whack him with thier maces, Luigi must lure the duo of living medevil armors onto one of the three rugs on the floor. For this to work, the player needs to lure both suits onto the same rug, then use his Poultergust 5000 to suck up the rug, tripping the suits, which force out the Possessors, who turn back into one in order to charge at him. In the second phase of this knight fight, the Possessor splits into three and possesses three suits of armor, the third phase, possessor splits into four and possesses, not four suits, but one gigantic suit of armor that stands in the middle of the arena. Luigi has to lure each leg onto a rug, trip one, then trip the other before the steel behemoth regains his balance. In phase four, Luigi just has to suck up the Possessor.

Facts
They have infinite HP, but can be defeated by ripping off their ghost skin, then when Luigi has sucked up all 3 skin layers the Possessor Ghost will be in The Poltergust 5000. Their main attack is to use the things they possess to hurt Luigi.

Trivia

 * The Possessor Ghosts are the only other ghost besides Polterpups and Boos that are white in Luigi's Mansion 2.
 * The Possessor Ghosts are the strongest ghosts in the entire Luigi's Mansion series based on their health formula which reads 3x∞ (three times infinite), referring to the fact that each layer of skin has infinite healthpoints.