Heritage of Pure Blood (Sorcerous Origins)
Over generations¸ your royal ancestors practised inbreeding to keep the blood of their children clean from the influence of the common people's heritage. Of course¸ this came at a price. The blood got thinner and thinner¸ and more and more children with genetic disorders were born. Some of them weren't strong enough to survive the first years of childhood. Some of them had been killed to extinct the weak from the line. But those who prevailed carried the arcane power of an ancient unearthly being in their veins. You survived your infancy and even though you show a mark of your parent's incest¸ you didn't fall victim to insanity or a bodily mutation. Now you are an accepted¸ probably feared¸ member of high society and your arcane power represents the supremacy of your royal lineage. In the Forgotten Realms¸ heirs of the pure blood can be found in the human nobility of Mulhorand¸ Nimbral¸ Unther and Thay; or in the matriarchy of the Drow (read more: Variant Rule "The Szarkai").