Cult of the Dragon
One of the weirder villainous organizations in the Forgotten Realms setting for Dungeons & Dragons, the Cult of the Dragon is a mad cult made up of humanoids who have turned to worshipping dracoliches as incarnate gods and see it as their holy duty to both entice more dragons to undergo the lich transformation, which they are happy to help with, and to aid dracoliches in their various schemes. They were founded by Sammaster, a former Chosen of Mystra who went insane when he couldn't accept that he had mistranslated a prophecy about dragons coming to rule Faerûn after some great apocalypse when he claimed that it would instead result in the world being ruled by undead dragons. Sammaster became a Lich himself to try and make his vision come to reality and was ultimately destroyed as part of a foiled plan to exploit the Rage of Dragons, an event that makes up the Year of Rogue Dragons trilogy of novels.
in 5e Tiamat provided the correct translation that it was not "Undead dragons sitting on thrones" but the "Dragons will Burninate evening, skeletonizing even ever person sitting on a throne". Switching the worship from undead Dragons to living chromatic Dragons, including their queen, herself. This gave here a godly foot hold the Untheric pantheon and allowed her to move that divine influence to the sword coast, cumulating in the module Rise of Tiamat, which they tried to fill the prophesy and release Tiamat from hell, but ended up some adventures beat her back down