The big draw of this book (to me, anyway) is the world-building which is rather unique. The story is based on a Chinese folktale but unlike other fantasy books rooted in Chinese falktales and mythology this one is set in the heavens, i.e. various immortal realms, and among Immortals. At times that made it hard for me to imagine how travelling between the realms really worked and the action set piece towards the end a bit confusing but other than that, I found it intriguing. The main characters are well-rounded and believable and I liked Xingyin's path in the Celestial Kingdom and the slower pace of that part. The writing style and the pacing are also a bit different from other fantasy books. I liked the realistic and bitter-sweet ending. Though it's part 1 of a duology it's a self-contained story. If you're into world-building, it's worth checking out.