At your touch, the target seems almost to leak. A tiny plume of jet-black mist emerges from his flesh, first in a trickle, then an ever-increasing stream.

The mist emerging from the subject is an illusion that only you can see. It constantly drifts from the subject to your location, providing a nearly foolproof way of finding and identifying the subject. The trail stretches for a number of miles equal to half your shadowcaster level, so it is possible for the target to escape your detection if he moves fast enough (or teleports). If the subject leaves the plane, the trail ends, though it resumes if he returns before the duration expires. The haze allows you to track the target, identify him if he disguises himself, or even locate the square he is in should he become invisible.