Sorcery

Sorcery is a form of magic in which the practitioner draws Na directly from a soul. A sorcerer could use their own soul as this source of power, but doing so is extremely taxing and requires a long period for recovery. Such a draining act often bleaches the color from the sorcerer's hair and skin leaving them pale and withered and can even, over time, warp the body into a monstrous shape.
To avoid such debilitation, most sorcerers use eldrich rituals to draw the soul from a living being and capture it inside a magical container, what the Golmarans called a Nurna'al. Most frequently, sorcerers use a gem for this purpose. Each soul requires it's own Nurna'al. Even when using a Nurna'al, such magic still carries risks for the sorcerer. If they make a mistake in weaving the spell, the magic could inadvertently draw its power from the sorcerer in addition to or instead of the Nurna'al. Powerful sorcerers also sometimes drain the Na from the living things around them, withering and blighting their vicinity.
As a result, sorcery is forbidden in most areas, but secret organizations exist around the world nonetheless.