K'thormir

K'thormir was the name taken by a gray elven adventurer named Faenwyn, after being corrupted by a malevolent force known as the Darkness. K'thormir was infamous for swowing chaos among the people of the overworld, and meddled most prominently in the affairs of the party known as the Sons of Shadowfell. In the demon's last confrontation with the guild, he was imprisoned within a dwarven puzzle cube currently posessed by the party.

History
Centuries before the current age, Faenwyn, a gray-elven adventurer and leader of a reasonably successful guild, ventured into the abandoned cave adjacent to the town of Amaanlu. The cave contained the fragmented remains of the malevolent spirit the darkness, and the presence coerced Faenwyn into becoming its Minion in return for great power. Faenwyn agreed, and cursed his party into becoming a race of sun-fearing abominations, who later came to be known as the Vai'kesh. Faenwyn renounced his name and took up the mantle of K'thormir, becoming a demon by the power of the darkness.

At some point in his conquest for the darkness, K'thormir was imprisoned in an ancient dwarven puzzle cube in a dwarven city now located geographically in the Brand of Fowl. The cube was found centuries later in the ruins of the city by a newly-formed band of adventurers. The adventurers were coerced into freeing the demon, allowing him to break free from his prison and resume in his attempt to free his Master.

K'thormir waged war against the people of the overworld, enlisting in the aid of orcish armies, and attempting to summon a demon army (although this attempt was thwarted by the same adventurers who freed him.) The demon created an army of monstrosities made up of tortured prisoners, known as the bound, and captured and harnessed the power of the demigod Calixto in order to posses the ability to change reality at will.

The demons conquests culminated with the sacking of Shadowfell Keep, in which his combined armies vastly outnumbered the military force of the city. Following the attack, the guild of adventurers traveled to the Vaikesh Citadel to discover how to bind K'thormir.

At the dwarven mines of Hoelbrak, K'thormir made his final stand against the heroes while attempting to create a rift in which to free the darkness. The demon was defeated by the heroes and bound once again to the dwarven puzzle cube, which is currently in the possession of the adventurers.