Ghosty

Ghosts are spirits of dead minifigures, that appear in many dark and isolated regions, and within some castles. The Ghost minifigure was originally released in the Castle theme, and it has become something of an icon for the theme. Three of them are major characters in Monster Fighters. There have been several different variations of the ghost released over the years.

Variations
The Ghost has appeared in four different physical variations across the years, not to mention the different types of ghosts that appears in various video games. All three contained a specifically designed headgear glowing in the dark, black head, plain white torso and white arms. The first one (1990 - 1995) having white hands and 1 x 2 white tile and brick for legs. The second (1997 - 2000) having a ghost head gear and standard minifigure white legs with white hands, and the third one (2006) having yellow hands and a darker/trans glowing in the dark headgear piece.

Original (1990 - 1995)
The original ghost minifigure, and also the longest lasting, featured a glow-in-the-dark cowl with a smiling expression moulded in it, a black face, and a white torso with white arms and hands. Unlike later versions, instead of having normal legs, a white 1 x 2 brick and tile were attached to the bottom of the torso.

Version Two (1997 - 2000)
The second ghost minifigure is generally what is regarded as "the classic ghost". It is identical to the previous version in all ways, except for the inclusion of normal white legs instead of the bricks used by the original.

Version Three (2006)
The third version of the ghost, which was the only one seen in the first decade of the 21st century, is almost identical to it's predecessor. The only difference is that while the older ghost has white hands, this version sports yellow versions.

Version Four (2012)
The fourth, and most recent ghost, was released in June 2012, in the Monster Fighters theme. With a black face, and white body and hands, it would appear to be most similar to the second version of the ghost, however, this is the only ghost so far to feature a radically redesigned cowl. It is more detailed, and shows a wailing expression, in contrast to the classic smiling face, as well as a molded tip for the cowl.

Version Five
There is also a ghost which looks like Version Four, but it has a brick instead of legs, like the Original Ghost. This ghost could probably be Version Five.

The LEGO Movie
In The LEGO Movie, the Ghost is among the Master Builders that meet in Cloud Cuckoo Land.

In LEGO Racers
In LEGO Racers, the ghost appears as an obstacle in some tracks, and looks much the same as the second variation, which was current when the game came out.

In LEGO Star Wars II: The Original Trilogy
In LEGO Star Wars II: The Original Trilogy, ghosts of several Star Wars characters appear, but they simply look like glowing transparent versions of their regular forms.

In LEGO Star Wars: The Complete Saga
Like in In LEGO Star Wars II: The Original Trilogy, in LEGO Star Wars: The Complete Saga, Force Ghosts appear of several characters.

In LEGO Battles
The ghost is a playable character in LEGO Battles. Here, it resembles it's classic appearance.

In LEGO Rock Band
There are several ghosts in LEGO Rock Band which are known as the Ghosts of Brickton Manor. There are transparent blue versions of normal minifigures without legs.

In LEGO Harry Potter Years 1-4 and 5-7
In the two LEGO Harry Potter games, ghost also much resemble the force ghost from Star Wars, in as that they are glowing transparent blue versions of normal minifigures.

LEGO The Lord of the Rings: The Video Game
The ghost of Boromir appeared in LEGO The Lord of the Rings: The Video Game.