Yogg-Saron is a god from the Warcraft franchise. He was made accessible to players in patch 3.1 of World of Warcraft: Wrath of the Lich King
, and is the final boss of the 10 or 25-man Ulduar
Yogg-Saron is an Old God, a parasitic entity that ruled the planet that came to be Azeroth
before the Titans came. Attacking the titans creations with the "Curse of Flesh", which would allow the Old Gods to better prey upon them, Yogg-Saron and his brethren warred against the titans for many years. Although the titans won, they found the Old Gods had infected Azeroth so deeply that they could not be destroyed without harming the planet as well. Instead, the titans imprisoned the Old Gods deep beneath the earth. Yogg-Saron would be sealed within the titan city/observation center of Ulduar
. But the Old Gods would not be contained so simply.
Ages later, after the War of the Ancients, the night elves and the Dragonflights sought to make a World Tree to watch over Azeroth. The first attempt, a tree named Vordrassil, had to be destroyed when the elves discovered something had corrupted the tree's energies. Only thousands of years later would it be discovered that Yogg-Saron was using Vordrassil as an attempt to regain his influence in the outside world.
Over the years, Yogg-Saron's blood, shed over much of Northrend
during the war with the titans, hardened into a metallic ore called saronite. This metal, thick with Yogg-Saron's evil, would later be used by the Undead Scourge in their weapons, armor, and buildings. Perhaps it was the use of his hardened blood to spread death and misery that strengthened the God of Death enough to break out of his ancient prison.
Yogg-Saron's first act of freedom was to strike back against his captors. Although most of the titans had left Azeroth
to seed other worlds, several had been left in Ulduar
to watch over Azeroth and guard Yogg-Saron. Careful to hide his escape, Yogg-Saron began to influence the mind of the "Prime Designate", Loken. Using Loken as a pawn, Yogg-Saron struck at the other titans in Ulduar. It was because of the Old God that Loken killed his brother Thorim's wife, Sif, blaming the killing on the titan Hodir's ice giant children. Yogg-Saron grew even more powerful from the ensuing conflict, corrupting the other titans as well. Once they had been captured, Yogg-Saron began directing Loken to build up his armies of iron to institute a new reign of terror.
Eventually, after many trials, a group of hardened adventurers, led by dwarven explorer Brann Bronzebeard
, assaulted Ulduar
. Fighting and slaying the crazed Loken, they first became aware of the extent of Yogg-Saron's reach. Delving into the depths of the city, they freed the other titans from Yogg-Saron's influence. Finally, in the ruins of his old prison, the Old God himself struck. The God sought to drive his attackers insane, directly attacking their minds and haunting them with troubling visions. Managing to shake off his influence, the adventurers clashed with the Beast of a Thousand Maws, finally striking a fatal blow. Although the God's reign had ended for good, his works had already done their damage. Loken's death signaled an ancient titan failsafe that would prove to be an even greater threat...