The book How the King of Elfhame Learned to Hate Stories follows the story of Cardan, the mischievous King of Elfhame, as he struggles to come to terms with his past and his role as a leader. The book includes details of Cardan's life before the events of the Folk of the Air trilogy, as well as an adventure that takes place after the events of the final book.  

I just finished reading it and I’m impressed since I usually don’t find prequels very interesting. As a fan of "The Folk of the Air" trilogy, I was thrilled to dive back into the world of Elfhame and experience the story from Cardan's perspective. Overall, "How the King of Elfhame Learned to Hate Stories" is a must-read for any fan of fantasy and Holly Black’s work. It provides a great backstory and conclusion to the series.