This is the third of the Hinterlandet adventures translated to English and converted to D&D 5th edition. The two previous adventures lead the protagonists to an abandoned tower and into the hidey hole of a lich king’s disciples, but this time the adventurers are lead to the ruins of a palace, and here they will lose their mind. You can find it here at DMs Guild: Palace of Sweet Dreams.
This module is from the story line “Seven Swords of the Dwarves”, which was about bands of adventurers looking for the legendary swords of the dwarves, and during the adventures some players succeeded in accidentally awakening the sleeping Dragon introducing the Dragon-story lines, which Tower of the Star Watcher was a part of. In its converted version, the story line about dwarves and swords have been removed. But there is still plenty to explore, as the palace is home to a group of mad people acting strange, and unwary PCs will end up among them, while they are fighting to survive flesh-eating plants and monstrous spiders (and for spoilery reasons I am being vague here, but the cause of madness finds its root in old sword & sorcery tropes).
We had a lot of fun with this module at the convention, where it was originally played, as the adventure does strange things to the adventurers’ sense of time and place. For the lucky players, great treasures await them. The adapted version has maintained most of the original material but added new hooks and a few other details, but it is now setting agnostic and maintains its use of non-balanced encounters. You can read more on the design principles behind Hinterlands adventures in this post.