One of the old gods from pre-history, not much is known about this distant history since his name and story have been actively purged from the histories. What is known is that when he and his daughters took refuge on Twilight World together with the rest of the Elves they left his wife Ithren behind who had died on Phantom World. An unknown time later there was a schism between his followers and the rest of Elvenkind, resulting in him Ascending to God of the Void and Necromancy, while his daughters and their followers who called themselves the Drow were exiled into the Underdark beneath Hadira. Ever since his Ascension worship of him was persecuted by both Elves and Humans resulting in him being worshipped only by the Drow and extremely secretive cults on the surface, most notable of which consisted of High Elves led by Malgali Forlonde.
His wife Ithren is worshipped by the Wood Elves as one of The Masked Host. During the turmoil of The Reckoning it turned out the rumors of her death were somewhat exaggerated and she returned to her daughters leading their people into the universe during The Diaspora.
Since The Reckoning a shadow war over the Void between Ilalokthramek and the new god Alvaro of The Travelers whose warrior-custodians preach that Ilalokthramek has been corrupted by an unspeakable evil and needs to be destroyed to bring back peace to the Void.