Few stories surrounding Valkorion are as chilling as the tale of Nathema. Long before assuming his current form, Valkorion was a Sith pureblood named Vitiate born on the lush and vibrant world of Medriaas. Vitiate rose to become Emperor of the Sith and ruled for over a thousand years--but only after extracting a terrible price.
Early in his reign, Vitiate invited thousands of the most powerful Sith Lords to his homeworld, then wiped out his would-be challengers in a profane dark side ritual that annihilated all life on the planet. Even the Force could not survive. The void that remained after the ritual brought pain and suffering to any Force-sensitive beings that approached.
The name Medriaas was purged from the galactic record and the barren planet became known as Nathema. Centuries later, Valkorion banished his daughter Vaylin to the blighted world, knowing the void would limit her growing power and make her more susceptible to the mental conditioning he could use to control her... if it didn't drive her mad.