No Prep Module: The Archfey's Wish (Patreon)

https://www.kassoon.com/dnd/adventure/no-prep-module-archfeys-wish/ 

An Archfey (Myathethil Xiloscient) from the feywild has discovered the power of wishes, and distorts them into the stuff of nightmares. The archfey has used the power of wishes to create a stronghold in Limbo which has distorted the landscape to repeat across itself like a never-ending pattern. As the archfey's wish powers have grown so has the danger, and now the land has become infested with demons and dragons, twisted and distorted into nightmarish abominations.