Mist horror

A mist horror was a spirit of an evil being that was originally from the Demiplane of Dread. A more powerful version of a mist horror was known as a wandering horror.

Description
Mist horrors had no fixed shape, and could take whatever form and size they decided, but usually appeared the size of humans. They were somewhat a form of undead, and as such, could be turned by experienced clerics. However, they could not be harmed by holy water or by other forms of damage that usually harmed undead.

Though very similar, wandering horrors were more dangerous versions of mist horrors and had chaotic dispositions. They seemed to be locked into more specific shapes, reflective of their evil deeds during their life. Wandering horrors were slightly more powerful in combat, but other than these differences, were essentially the same as mist horrors.

Behavior
Mist horrors could take the form of that which their enemies were afraid of, as well as sending them horrifying thoughts.

Combat
The horrors often caught their opponents off guard after they had assembled their desired physical forms. They struck out once their foes had stopped moving, in any way their form allowed, though they were limited to using two attacks in single maneuvers. These spirits could only be hit with weapons of +2 enchantment or higher.

They also had innate magic resistance auras that spanned 20 feet (6 meters), and so would cancel spells that were cast in the area. As this was in the form of telempathic waves, only spells directly cast were affected, and not spells from items, such as wands. In addition to their magic resistance, they could not be charmed, as they were essentially incorporeal, and thus were also immune to becoming blind.

Ecology
Despite originating from the Demiplane of Dread, both mist and wandering horrors were known to exist around Faerûn.

Appearances

 * Video games
 * Baldur's Gate II: Shadows of Amn