Slammer

A Slammer is a type of ghost that appears in Luigi's Mansion: Dark Moon. They are quite large and somewhat resemble Blue Twirlers from the original game. They are slow-mowing, red tough ghosts with 30 HP each, making them somewhat more resistant to the Poltergust 5000. They are usually encountered alone while serving as a melee tank to allow other ghosts to attack Luigi.

Abilities
Slammers, much like Blue Twirlers, have the ability to create shock waves in front of them by clapping their hands together. They can also rip objects, like gears, right off (through) the walls due to their strength. If Luigi looks at one right before it attacks, it will stop, look around itself, then vanish before reappearing somewhere else, preventing any damage from being done to him or the environment.

Trivia

 * After the Dark Moon was restored at the end of the game, you can see that the real personality of a Slammer is very kind, selfless, and caring, even though Slammers do look tough and mean.
 * E.Gadd also describes Slammers in the vault these things, also adding "Just don't let them give you an encore!"