G'huun

G'huun (pronounced GU-hoon) was an Old God inadvertently created by the Pantheon during their experiments on the other imprisoned Old Gods, as the Titans tried to find a solution to the problem that they posed. Worshiped by the Blood Trolls of Nazmir as a loa, G'huun was known as the Blood God. Though it was quite less powerful than the other Old Gods, the threat it posed was still world-ending. G'huun's corruption was called "underrot". It sought to spread its rot, pestilence, and decay across the world and beyond, and to consume Azeroth in the process.

Origins
G'huun was accidentally created by the Titans when they experimented with means to solve the problem posed by the Old Gods. They used Uldir to "try to figure out what makes Old Gods tick", including performing experiments. This led to "some creepy and weird stuff inside it", and G'huun is the result of years of experiments where the Titans couldn't figure out how to cure this Old God disease. When they experimented upon the Old Gods' unending, ravenous need to corrupt, they unexpectedly created a perfect avatar of that desire. G'huun is nothing but rot, pestilence, and decay, the ultimate parasite who cannot stop itself from consuming its host until it is gone. He was locked away in the facility of Uldir sealed with three seals: Nazwatha in Nazmir, Atul'Aman in Vol'dun, and the Great Seal of Dazar'alor in Zuldazar. The seal in Atul'Aman was destroyed by Mythrax the Unraveler long ago, while Nazwatha was damaged by the Cataclysm.

During the final era of the Council of Tribes, an attempt to summon Hakkar the Soulflayer was made, which released a plague of corrupted blood, killing thousands of trolls. It was deemed that the bodies, too polluted for proper burial, would instead be burned and kept in special urns. As time progressed, this method became commonplace among the Zandalari in disposing of their dead. After the great plague, there were still those who clung to the magic of the blood god. They tested their magic and perfected them. One such relic was a totem, which when concentrated upon, would drain not just the life from their enemies, but also their blood, infusing the caster with it and altering them in unusual ways. This was the dawn of who the Zandalari call, "the blood trolls". Eventually, the blood trolls would begin worshiping G'huun. Because G'huun has no need for technology, the blood trolls regressed into a more primitive state compared to other troll races. Grand Ma'da Ateena and the blood trolls considered themselves the children of G'huun.

Battle for Azeroth
With his prison weakened, G'huun's corruption begun spreading across the land, threatening to cover all of Azeroth. He also started wresting control over the souls of the dead from Bwonsamdi, the loa of death, leading to a conflict between them.

G'huun corrupted Hir'eek, the loa of bats, and turned him into his servant. Adventurers worked alongside Jo'chunga and struck Hir'eek down in order to weaken G'huun's forces.

With the seal of Atul'Aman destroyed by Mythrax, and the seal of Nazwatha destroyed by the Cataclysm, Zul and his allies, General Jakra'zet and Yazma, worked to free the Blood God by undoing the last remaining seal, in Zuldazar. The plan was to have G'huun replace the loa, which Zul saw as weak, as the trolls' new god who would lead them to rule the world again. The seal was ultimately destroyed by a revived Mythrax during the invasion of Dazar'alor. A group of adventurers entered Uldir and slew G'huun before he could break free.

Notes and trivia

 * Although they are both Blood Gods and worshiped by the trolls, G'huun is unrelated to Hakkar the Soulflayer.
 * He was also referred to by Jeremy Feasel as an "Old God type creature".

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