Beautiful Lady Tyrell,
I've taken the time to compile what I know of Zovaldar and his artifacts for you, I hope it's useful.
Harlow R. Penrose
The story of Zovaldar begins, by his own words, millenia ago on the surface. Zovaldar was once the king of a mighty tribe of Fire Giants, and a powerful priest of Surtur. Unlike many, who desire wealth, or power, he desired song, the song of pixies. This unatural pixie fetish led him to be reviled by his tribe, and it's distraction nearly resulted in his death when his throne was challenged by another. Zovaldar escaped though, entering into a long exile. He went wandering over many, many years. Down into the Underdark, down through Undermountain, the domain of the mad wizard Halaster Blackcloak. Zovaldar was weak of mind, and he was ensnared by the magics and the maze of Halaster. The mad wizard was fascinated by Zovaldar, and considered him something of a game, or toy; an instrument of further amusements.How he was slain and mummified isn't known, his path after Undermountain is murky at best. It is known that Halaster Blackcloak gave him his boots, and axe, and possibly his helm aswell, these artifacts giving him great and terrible power. The fourth 'artifact' Zovaldar carried, a pixie, was likely taken with him when he was exiled from his tribe. Zovaldar likely lost all upon his death. Three of the artifacts, the boots, helm, and axe, have been traced to bouts of insanity in their possessors, likely the intention of the mad Halaster. Whether it happened before, or after his death and undeath is also unclear, but Zovaldar saved many Formians from enslavement and thralldom to the Illithids and Beholders of the Sand Caverns. He treated them well, and protected them, and in turn gained their loyalty. Eventually though, he turned on them himself. They became enslaved, and enthralled, to him. This is why the Formians served Zovaldar, they had no choice under his dark influence. Zovaldar directed them and other human servants, assassins, to find his artifacts and recover them. The Formians served him from a shrine above his crypt, a crypt they likely had a hand in building.
Of his artifacts; the axe was found and taken by Sanctuarian adventurers in the Sand Caverns, recovered from the bodies of Drow, who were hired to retrieve the axe, and driven mad by it. They slain by Illithids who wished the item for themselves. The axe eventually, likely through his human assassins, came back to Zovaldar's hands. The helmet was recovered by Valaron Sunellar during the raid of a dark temple to Lloth, there a Matron Mother was raising an army of Driders. She had turned on many of her fellow drow, driven mad by the artifact. It's also likely she was the one who'd hired the Drow trying to recover the axe. The helmet's origins go back beyond Zovaldar himself, and it was purified of evil by the spirit of Saint Andrew of Torm, who was freed from imprisonment under of a demon of shadow by Valaron Sunellar, Harlow Penrose, and others. Through Saint Andrew's will and a sacrifice on behalf of Sunellar it was cleansed. Zovaldar's boots were taken by Harlow Penrose from the feet of a lich who dwelled upon an island in the Dark Lake. Not long after, he was subjected to dreams, demanding the boots return, and lost them to Zovaldar while trying to investigate. The path of the pixie is unknown, but Zovaldar believed it to be in Sslal'teesh, which prompted his attack there, to recover it.
It's Sunellar's possession of the helm, and possibly the pixie, which led Zovaldar and his formian minions to attack Sanctuary. At the gates of Sanctuary, Saint Andrew again appeared, and sacrificed the last of his essence to shatter the artifacts of the Fire Giant. Zovaldar retreated, back to his tomb, and was pursued there through a magic portal by Valaron Sunellar, Harlow Penrose, Alyssara Nil'vara, Jaden Sarkish, Kald Blake, Eva Kelm, Kharl Khemed, Harold Hatnine, Gegan Bruntlet, Alabaster Rubyglow, and Leonard Merrickson. In the final battle against the giant, Zovaldar called upon the power of his god Surtur and slew Kharl Khemed, before finally being vanquished himself. His tomb was smashed upon his death, ending the threat once and for all; and revealing Halaster Blackcloak himself, who gave exposition on the events that had nearly overtaken Sanctuary. The Formians, now freed from the grip of the Fire Giant, destroyed all idols to his power and went about restoring their hive. Zovaldar's story ends, tragically, with his soul now in the mad grasp of Halaster, the final cost of a dangerous obession with the music of pixies.