Out of the Darkness and Into the Light
As the knot of mist flows forward, it becomes apparent that it is composed of hundreds of tiny mistlings of vaguely humanoid shape. Their bodies consist of arms and a torso which trail off into indistinct vapor.
Scarlet dancers are vaporous undead believed to be miniature versions of the deadly crimson death. Found mostly in sewers and other subterranean areas teeming with vermin, these tiny undead gather in clusters of over a hundred of their kind. Scarlet dancers instinctively flee from sunlight, despite it causing them no real harm.
Scarlet dancers have an innate hunger for the blood of the living, and, as such, spend all their time seeking out warm-blooded creatures upon which to feed. Once sated, the swarm falls into a torpor for a few hours, before its eternal cravings resume. Although they are opportunity predators, feeding mostly on the vermin found in the sewers where they cluster, scarlet dancers prefer the blood of humanoids.
A single scarlet dancer is about 2 inches in diameter and weightless. Its coloration is grayish-white, but as it feeds, the mist turns blood-red.
Scarlet dancers do not speak.