Eltab Eltab is a demon lord known as the " Lord of the Hidden Layer . " Description . Eltab appears as a fifteen - foot - tall humanoid with the head of a canine - like creature . His head sports numerous antlers and horns and his body is covered with bony dark red plates . He has slitted yellow glowing eyes . Realm . Eltab rules the 248th layer of the Abyss known as the Hidden Layer . It is a vast wasteland of boulders and fissures constantly beset with intensive electrical storms , making it inimical to most life except for demons and deadly plant life such as viper tree s , ironmaw s , and bloodthorn s . In the past thousand years or so , because of Eltab ’ s absence , the Hidden Layer has been fragmented in ever - changing fiefdoms as Eltab ’ s former lieutenants , including the balor Ndulu , fight over the vacated realm . Thanks to the bindings cast by the Narfell i demon - binders on Eltab when they summoned him , they also somehow linked fragments of the Hidden Layer into Faerûn , as well . So pieces of the layer , known as demoncysts , are lying scattered beneath the ground all over northeast Faerûn . Demoncysts are typically a hundred feet or more in diameter . The environment of the cyst does not interact with the surrounding terrestrial environment ( and vice versa ) , thus each cyst resembles a cave that contains a wholly different environment than the surrounding earth or open space . Some cysts are empty , but others contain fiends and / or servants of Eltab . The largest cyst , known as the Hall of the Hidden Throne , lies in Eltab ’ s current location , the Citadel of Conjurers . This cyst contains Eltab ’ s palace and the calling circle that tied Eltab to the Realms . In fact , until this circle is destroyed , Eltab cannot leave Faerûn or return to the Abyss . History . The demon lord Eltab was a potent force in the Abyss , rivaling the powers of Graz ' zt , Orcus and even Demogorgon himself . However , during the ancient days of Faerûn , the empires of Narfell and Raumathar engaged in a bitter war , which ultimately destroyed both empires . During this war , Eltab was summoned to Faerûn by the so - called demon - binders of Narfell , so he could be used as a pawn against their hated enemy . Eltab lead a demonic horde on the behalf of Narfell and invaded Raumathan , a city of Rashemen , which he quickly conquered and set up himself up as its ruler . Eltab ’ s rule was brief , as an alliance of spell - casters ( including the Witches of Rashemen ) overthrew Eltab . Eltab was forced to flee , but the Rashemi witches caught up with him in the Sharawood , imprisoning him beneath the ground , and bound a dracolich called the Everlasting Wyrm to guard over him . A hundred or so years later , followers of the dark god Myrkul , intending to plunder the hoard of the Everlasting Wyrm , discovered the imprisoned demon lord . They agreed to release Eltab under the condition that he serve Myrkul ’ s church for ninety - nine years . With Eltab ’ s aid , the followers of Myrkul took control of the city of Shandaular and in its place , established the theocratic city of Eltabranar . Later , Eltab prompted an ill - fated invasion of the nations of Unther and Mulhorand . Eltab was once again imprisoned , this time by the god - kings who led Mulhorand , into a demoncyst beneath Thaymount . The infamous Red Wizards found Eltab more than seven hundred years later . The wizards used an ancient Narfelli demon - binding ritual and called Eltab forth to assist them in their war with the Mulhorandi god - kings . The god - kings ’ armies were routed and the nation of Thay was established . When the Red Wizards found they could not dismiss Eltab , they imprisoned him near the mouth of the river that now is named after the demon lord and built a capital city named Eltabbar over the prison . More recently , the Thayan lich Szass Tam realized that Eltab would soon break out of his prison . He deliberately released Eltab with the intention of using a spell to permanently enslave the demon lord . But his plan was foiled by a group of adventurers , allowing Eltab to escape into a demoncyst below Thaymount . During a retaliatory confrontation with Szass Tam , Eltab was seemingly destroyed , but thanks to the binding cast on him by the ancient Narfelli demon - binders , he was magically transported to the Citadel of Conjurers in the nation of Impiltur , where he is currently plotting new plans for conquests and revenge . Publishing history . Eltab was first mentioned in " Dreams of the Red Wizards " , and debuted in the " Dungeons & Dragons " second edition supplement " Spellbound " . He made his third edition debut in " Champions of Ruin " , and is also mentioned in " " , " Lost Empires of Faerûn " , and " Dragon " # 355 .