Basher

A Basher is a removed ghost in Luigi's Mansion. They only appear in the E3 and the Nintendo Difference pre-releases of the game. They were most likely removed because it was planned to be a fake-horror game and the teeth that it had on its mouth was pretty innapropriate and scary for the kids that would play it.

Appearance
The Bashers would look similar to Gold Ghost, but they face would be a little smaller; their eyes would be smaller and also their mouth. All of the Bashers have two teeth in their mouths.

They would appear in more color variations, usually pinkish-white; and they could be also orange, pink and dark purple in hallways and some rooms like the Dining Room and the Nursery (named the Child room in the pre-release.)

Attack method
Normal Bashers (Pinkish-white, orange and dark-pink colored) would attack exactly like the same as the final game; except that their blow would take out 10 HP instead of taking out 5 HP in the final game (Normal mansion only; in Hidden Mansion its normal attack is doubled.) The Purple Bashers only do their work usually in the hallways; and when Luigi gets next to one and at its opposite direction, a blueish white dust-like light would be triggered on the floor and if the player didn't go away in time Luigi would be scared, with the camera zooming in him and the ghost and a animated "BAHHHHHH" would appear next to the characters; and half of his HP would taken out. The ghost then laughs and de-spawns.

Trivia

 * The Basher would be eventually replaced in place by the Bowling Ghost.
 * The purple-colored Basher is most likely the ghost that inspired the Sneaker from Luigi's Mansion 2, as they both have the same basic function--scaring Luigi, except the Sneaker does not hurt him in the process.
 * There is a similar unused attack present in the code of the game called "EnFrighten". The attack is not even near to the same as seen on the E3 pre-release, since the process consist of: when the ghost is triggered by Luigi's flashlight, he would use the also unused animation "appear.key" and would drop a bomb quickly and laugh. In the video the attack was shown it is possible to note that the ghost is covering his face; possibly revealing it would be invisible.
 * How the name "Basher" was originated is a mystery; even if its true name wasn't known it was accepted by most of the community still.