Mists

The Mists are a strange supernatural phenomenon seemingly bound to the fates of Dread Lord Strahd von Zarovich, and the County of Barovia at large. The Mists appear to be somewhat aware, being able to discern intention and identity in those who pass through them: the Mists allow people to enter Barovia, but only allow the Vistani to leave. Anyone else who attempts to leave will find themselves turned around, hopelessly lost forever until they decide to find their way back to Barovia, at which point they will quickly find themselves where they first entered the Mists.
It is known that, during the few instances that Strahd von Zarovich has been momentarily "killed" that the Mists have fallen, most recently during the Fourth Mistfall. During these episodes, which only ever last for three nights, the Mists dissipate and people can move freely through them. Strangely, when the Mists fall, the County appears to be in a section of the world where it was once found. Should one attempt to go to that place when the Mists are risen, they simply cannot find it...
Scholars have spent centuries studying and attempting to understand the Mists, including at the behest and funding of Strahd himself, but to no avail.

Type

Metaphysical, Supernatural