Basil II's Leader Ability is Porphyrogénnētos. The Byzantine Empire in Civilization VI brings unique units, buildings and traits with it. He is well known for his conquer of Ancient Bulgaria and his rule is considered one of the greatest in Byzantine history, with his many military exploits leading Byzantium into the height of its power. The civilization is led by Basil II, who ruled from 976-1025 CE. Byzantium, circa 976 CE, is slated to be a religious and military powerhouse, leaning towards both victory paths.