Kyuss, also known as the "Worm that Walks," was an Elder Evil prophesied to usher in the "Age of Worms," a prophesied time when the undead of Corwyn will rise up and destroy the world.
Description
The Worm that Walks is described as a 30 foot (9 meters) tall giant composed of a shifting mass of maggots and worms filled with the psychic imprint of a former demigod named Kyuss.
History
Thousands of years ago, Kyuss was a corrupt priest , whose depraved experiments with necromancy and his obsession with the undead led to his banishment from his home in the Barrens.
While in exile, Kyuss gathered a vast group of outcasts and loyal followers. Together, they sailed far to the south on a great pilgrimage to the vast, harsh jungles of Azoria.
On those far-distant tropical shores, Kyuss and his followers discovered the ruins of Koloth-Mar, a city of monoliths and vine-snared idols to alien gods. After the discovery, Kyuss told his followers of his mysterious visions—of massive metal plates foretelling the collapse of civilization. For many years, the cult of Kyuss rebuilt the city, while also scouring the dark jungle for the hidden artifacts. Eventually, the cultists found the plates, which confirmed their leader's apocalyptic premonitions.
The metal plates were made by the Spell-Weavers; a long-dead, alien culture whose civilization has crumbled a millennia earlier. The plates spoke of an era of chaos and destruction, known as the Age of Worms. To Kyuss, it was confirmation of his divine visions.
To fulfill the prophecy, Kyuss bound himself to a basalt monolith in the center of the ruins called the Spire of Long Shadows. The massive stones thrummed with living energy, and their poisonous whispers spoke to Kyuss, urging him and his followers to join them in oblivion.
In a strange, horrific ritual, Kyuss merged his physical form with the stones of the ancient monolith. In so doing, he became more than human, but his essence became trapped forever in a horrific demi-plane within the spire.
As the unholy ceremony took place, the followers of Kyuss destroyed themselves in a blood-soaked frenzy of murder and suicide. As Kyuss' followers sacrificed themselves for the glory of his vision, the twisted prophet declared himself the Harbinger of the Age of Worms. His mortal for then vanished forever.
In the centuries that followed, the jungles once again swallowed the spell-weaver city, leaving only the forlorn Spire of Long Shadows to peek above the lush tropical canopy. Today, much of the legend of Kyuss remains a mystery to sages. His only known legacy are foul undead creatures called the "Spawn of Kyuss."