The tainted are the result of the unholy touch by chaos itself. Many tainted actively chose to become chaos-touched, relishing in their newfound powers. However, tainted can be the result of extended exposure to the warp, or even the result of an unholy union of daemons, warp creatures, heretics, or otherwise.
Tainted are derived from any race’s bloodline, and in the broadest sense possible, still look as such. However, their unholy heritage has left a clear imprint on their appearance. Many of the tainted have large horns, tails, pointed teeth, split pupils, discolored skin, and other abnormalities. It isn’t uncommon for tainted to be killed at birth or die very young—whether from a merciful execution or as a sacrifice to a greater power.
Tainted subsist in small minorities found on the outlier of civilization. On feudal and feral worlds, they can be regarded as an ill omen but allowed to exist in peace, for fear their death will bring a curse upon the tribe that birthed them. Other tainted may be found by a radical inquisitor or chaos warband, using their powers for a purpose rather than being shunned by society.