The Great Undertaking

To appease the living and to extend the lives of the Drow the King of Blood brought the greatest minds of the Drow together to figure out a way to remove the curse upon the island of Forbuho. With the weight of ages upon the living subjects their lives lasted decades as opposed to centuries. For almost a hundred years the scholars, sages, wizards, and philosophers all worked themselves to death and beyond to solve the curse of the island. Eventually they conceived of the Great Undertaking, a ritual to move the connection to the various planes and free the island. Gathering the greatest minds and strongest spell casters of divine and arcane skills the majority of Drow nobility all gathered around the city of Obsidian. When the ritual was completed a silence fell upon the island and for three days no living or undead Drow heard from the city of Obsidian.
Eventually a few brave Drow went to the heart of the island to learn what happened to the Great Undertaking, there they saw the entire city of Obsidian dead. Not just the death of a mortal but the true death that claimed all souls including that of the King of Blood. But their efforts had produced some success, upon stepping into the city the Drow felt the weight of ages lift off their shoulders. Soon all Drow from across the island settled within Obsidian, going so far as to plant crops within the city to reduce the need to leave. Without the greatest of their Undead the living outnumbered and outpowered the dead and for the first time in ages a living King rose to power. But all was not well as the city itself soon vanished from the island not to be seen till the two kingdoms settled upon the island more than a thousand years later.