The ancient Sith on Korriban–not an order of Force users, but a distinct species native to the planet–were distinctive for their yellow eyes and blood-red skin. But the warrior Adas was unlike his brothers; his skin was jet-black and he towered over his fellow Sith. Through violence and cunning, he fought his way to become ruler of the Sith and united their nations through a bloody war. He later took the title “Sith'ari,” meaning “overlord.”
King Adas's ascension may have been helped by an untrained Force sensitivity. Certainly Adas was long-lived; his reign lasted three hundred years, and only came to an end when the Infinite Empire launched an assault on Korriban. The title Sith'ari remains a key tenet of Sith lore, eventually coming to refer to a perfect being in Sith philosophy.