Introduction

Thank you for your request, it was an interesting and insightful investigation, though we are sorry that we did not return more concrete answers. Below you will find a summary of our thoughts and conclusions.

Schools of Magic

• Abjuration “Protecting stuff” (Abjure: to renounce)
  • Definition: Abjuration spells and effects create magical barriers, negate harmful effects, harm trespassers, or banish creatures to other planes.
  • Examples: Alarm, Protection from Evil and Good, Arcane Lock, Glyph of Warding
  • Possible contributors to “purple mist” search:
    • Banishment (Positive Abjuration)
      • Several “banishment” type spells and effects have mist-like side effects. A banishment the size of a city would require immense magical energy and the hamlet described seemed native to not only the Prime Material plane but actually to Faerun. Banishment, or any other positive application of abjuration magic, seems unlikely.
    • Note: Positive Abjuration: Protection
      • A powerful Abjuration barrier, encompassing the whole hamlet could certainly coincide with the rising of mist that obscures the location and coalesces into a solid barrier. But in this case the people and the town are gone, not protected.
        
    • Creation of destruction of Barriers (Positive or Negative Abjuration):
      • Several “barrier” type spells and effects have mist- or smoke- like side effects when either created/built or broken/removed. T
        • The creation of a powerful Abjuration barrier, encompassing the whole hamlet could certainly coincide with the rising of mist that obscures the location and coalesces into a solid barrier. But in this case the people and the town are gone, not protected.
          
        • The removal of an Abjuration barrier of a size to protect a village could have caused the effects described. However, one would expect that such a barrier would be notable for its size and power (and therefore present in our records), and, while a negative abjuration event could explain the purple mist described, it does not work to explain the disappearance of the hamlet or any effects on the reporting subject. It seems likely that if the removal of an Abjuration barrier was involved, it was paired with some other powerful magic.
• Conjuration “Making stuff” (Conjure: to create)
  • Definition: Conjuration spells and effects involve the creation or transportation of objects and creatures from one location to another. Some spells summon creatures or objects to the caster’s side, whereas others allow the caster to teleport to another location. Some conjurations create objects or effects out of nothing.
  • Examples: Entangle, Fog Cloud, Dimension Door, Cloudkill, Teleport, Wish
  • Possible contributors to “purple mist” search:
    • “Cloud” spells and effects. If the request were just about the appearance of a purple mist, a “cloud” spell or effect would be the obvious first area of inquiry. In this case, the purple mist itself could have certainly been the result of a “cloud” spell or effect, but it would have been paired with some other powerful magic to account for the disappearance of the hamlet.
    • “Teleportation” spells and effects. In theory, “teleportation” spells and effects are consistent with both the purple mist and the disappearance of the hamlet. But the size and scope of the effect mean the involvement with extraordinarily powerful beings. There are no known examples of similar circumstances resulting from the actions from a single individual, even an Archmage or High Priest(ess). Rather, what parallel examples exist in the literature are the result of powerful magics by groups or gods.
      • Teleportation circles are often reported to leave mists/dusts/glitter behind after use, and often of a purple hue.
      • There are reports/legends that the city of Orkport was transported to the Shadowfell as part of a major incursion ~250 DR. The reports include descriptions of the land being covered by a sooty mist with a purple tinge, and all remains of the city itself transported to the Shadowfell. Some reports include multiple humanoid sacrifices to dark entities. (In this case, it would stand to reason that the Shadowfell connection could have blended with the purple coming from the purple of the telportation magic used, but this is just conjecture.)
      • Several adventurers have reported encounters with grey Mists that took them into closed domains within the Shadowfell, collectively refrred to as Domains of Dread. Villages, hamlets, and even small cities have been reported in these domains. The people in these communities uniformly displayed the typical darkened affect of long-term denizens of the Shadowfell, though the nature of the Mists often made these communities appear near local areas.
    • While there are no known direct parallels in the literature, if the effect was real and was magical, Conjuration magic seems a leading contender for the cause.
• Divination “Knowing stuff” (Divine: discover or learn)
  • Definition: Divination spells and effects reveal information.
  • Examples: Identify, Speak with Animals, Detect Thoughts, See Invisibility, Scrying
  • Possible contributors to “purple mist” search:
    • Divination may be useful in resolving this mystery, but seems incredibly unlikely to have been the cause.
    • Kitchen-sink note: the story with the blood. If the steps in the story were more discrete than described, then a divination-involved story could be imagined where a blood ritual demonstrated the location of a thing, which led to whatever actually happened with the purple mist and the hamlet. There are many stories where blood magic was used in divination, although those generally use the blood to find the subject who shed the blood, rather than to power divination blood magic directly. (This is a broad request with few details. We’re trying here.)
• Enchantment “Convincing stuff” (Enchant: to cause someone to act in a way it usually wouldn’t)
  • Definition: Enchantment spells and effects affect the minds of others, influencing or controlling their behavior.
  • Examples: Charm Person, Sleep, Hold Person, Zone of Truth, Power Word Kill
  • Possible contributors to “purple mist” search:
    • “Fog” and “mist” are commonly used to describe places that are enchanted (haunted). Records are plentiful, though they mostly leave out color (“thick fog”, “grey mist”, “swirling mist with sparkles of light”, etc.). Those that do include color seem to be referencing illumination of the place (“the green throbbing orb made the fog glow with a poisonous tint”) or the feelings of the observer (“the blue mist sucked the energy to live from us”) as much as it did an actual color of the mist (“the orange fog billowing down the mountain smelled of sulphur and left a sticky orange residue on everything it touched”).
      • Might the location in question have been enchanted during the observation, resulting in the observed purple mist?
    • Sparkly bits in the air: during enchantments, sparkles in the air are regularly observed. The color tends to be consistent within a given enchantment, but can vary widely between enchantments. The color here provides no useful feedback about what enchantment might have caused the sparkles.
    • Blood magic: we hesitate to include this note for obvious ethical reasons. Our internal review noted that this was an informational request, not a pragmatic one. This information is not to be used in the development of new practices or retrenchment of old ones.
      • Numerous records describe the use of blood magic to empower enchantments.
      • Blood itself is commonly used to bind souls and contracts, though we could find no reports of enchantments of this type generating fog of any form. The results tend to be of the “glow” rather than “mist” variety.
      • More general “blood magic” that uses the life-force of subjects is described in the literature, and a treatment that effected multiple subjects is quite consistent with a fog or mist application.
        • There are reports of cities being enchanted with magical illnesses, causing “living zombie” conditions and/or complete social breakdown. The application in these scenarios is consistent with this request, but the results are not. The people may disappear, but the buildings would remain.
        • There is the famous case of the Sleeping Curse put on a princess and her entire kingdom, causing everyone inside the kingdom to fall into a hundred years’ sleep when the princess pricked her finger on a spindle. Blood magic was clearly involved (beyond just the finger prick), and the kingdom itself was enveloped in a supernatural fog.
          • In this case, the physical kingdom remained and remained accessable, but one could imagine such powerful magic being paired with similarly powerful teleportation that put the kingdom into a pocket dimension or demi-plane or abjuration that locked the kingdom behind an impenitrable veil.
          • Since the observer returned to the location and was not stopped by a magical obstruction, that scenario would not be possible in this particular case.
• Evocation “Making energy stuff” (Evoke: cause an effect)
  • Definition: Evocation spells and effects manipulate magical energy to produce a desired effect. Some call up blasts of fire or lightning. Others channel positive energy to heal wounds.
  • Examples: Fire Bolt, Light, Cure Wounds, Heal, Magic Missile, Spiritual Weapon, Earthquake, Telepathy
  • Possible contributors to “purple mist” search:
    • Generally, the results of evocation magic tend to be more…accute.. than are described in this request. Fireball spells certainly leave a cloud of smoke and dust that could be considered a mist, but this report seems to describe a more slow-moving effect.
    • If one were to stretch credulity, then an incredibly powerful event of healing magic could conceivably generate a healing mist (purple even) that surrounded the town and healed the occupants of some horrible disease or malady (lycanthopy? vamparism?). But even these hypothetical seem to differ widely from the description of the people and the town disappearing.
• Illusion “Tricking stuff” (Illusion: a deception)
  • Definition: Illusion spells and effects deceive the senses or minds of others.
  • Examples: Invisibility, Magic Mouth, Simulacrum
  • Possible contributors to “purple mist” search:
    • Illusion magic or effects could easily have generated some or all of the observations, but with some counter-intuitive results.
      • Most obviously, were the reporting party subject to Illusion effects, then they could have experienced both the purple mist and the later visit to the location as illusions rather than reality. (Has anyone confirmed independently that the hamlet was originally there but is now gone?). The disappearance of one’s hometown could certainly fit within the “deepest fears” of the Weird spell, though the typical application of that spell generates something more akin to a monster.
      • Assuming the reports themselves were accurate, an illusion could also explain the initial report of purple mist. Illusion magic could not destroy a village directly, but it could hide any number of nefarious deeds behind the illusory curtain. Mirage Arcane, if somehow made permanent, could have masked an empty village and made it look, sound, feel, and smell as if there never was a village in that spot.
• Necromancy “Dead stuff” (Necro: death)
  • Definition: Necromancy spells and effects manipulate the energies of life and death. Such spells can grant an extra reserve of life force, drain the life energy from another creature, create the undead, or even bring the dead back to life.
  • Examples: Chill Touch, Spare the Dying, False Life, Blindness/Deafness, Gentle Repose, Resurrection
  • Possible contributors to “purple mist” search:
    • Combined with some strong mundane, Conjuration, or Evocation effect to actually kill the populace, sure Necromancy could account for the purple mist and the disappearance of the populace. But the raising of an undead army tends to cause notice (especially when raised from the recently-living), and Necromancy still does not account for the disappearance of the structures.
• Transmutation “Changing stuff” (Transmute: to change)
  • Definition: Transmutation spells and effects change the properties of a creature, object, or environment. They might turn an enemy into a harmless creature, bolster the strength of an ally, make an object move at the caster’s command, or enhance a creature’s innate healing abilities to rapidly recover from injury.
  • Example: Mending, Prestidigitation, Darkvision, Knock, Polymorph, Time Stop
  • Possible contributors to “purple mist” search:
    • Polymorph? Time Stop? No, the records do not indicate much of Transmutation that fit the overall request here.

Other notes

• The Color Purple
  • In terms of Schools of Magic, the color purple is indeterminate. Several schools have mist-like effects with a purple or violet hue, and the other characteristics described seem more pertinent to that conversation.
  • There are other inferences we can draw from the description of the color purple, however:
    • Purple is not regularly associated with Fiendish (neither Devilish nor Demonic) activities, even though the capture of populations to be sent to “hell” is a common trope throughout history.
• Planes of Existance
  • A note on Planes: the Transitive Planes
  • The Ethereal Plane and the Astral Plane are often called the Transitive Planes. They are mostly featureless realms that serve primarily as ways to Travel from one plane to another. Spells such as Etherealness and Astral Projection allow characters to enter these planes and traverse them to reach The Planes beyond.
  • The Ethereal Plane is a misty, fog–bound dimension that is sometimes described as a great ocean. Its shores, called the Border Ethereal, overlap the Material Plane and the Inner Planes, so that every Location on those planes has a corresponding Location on the Ethereal Plane. Certain creatures can see into the Border Ethereal, and the See Invisibility and True Seeing spell grant that ability. Some magical Effects also extend from the Material Plane into the Border Ethereal, particularly Effects that use force energy such as Forcecage and Wall of Force. The depths of the plane, the Deep Ethereal, are a region of swirling mists and colorful fogs.
  • The Astral Plane is the realm of thought and dream, where visitors Travel as disembodied souls to reach The Planes of the divine and demonic. It is a great, silvery sea, the same Above and Below, with swirling wisps of white and gray streaking among motes of light resembling distant stars. Erratic Whirlpools of color flicker in midair like spinning coins. Occasional bits of solid matter can be found here, but most of the Astral Plane is an endless, open domain.

Conclusion

We are sorry to have been of so little help in finding a precise explaination or parallel case. The details here are sparse and surprising, and our research seems exhaustive given those constraints. Perhaps an investigation into the site itself along with appropriately powerful magic to identify and describe any magical echos (or lack thereof) might give further guidance. Or possibly research other paths related to the people involved (no doubt, this is of little help). We are sorry we could not do more, and wish you well in your investigation.