This movie had so much potential: it had actual writing as base material, it had a great cast, the animation team was decent and it was released in a period of not much happening. It could have been like a new (old) Pixar movie release. Instead, it was a lazy, formulaic, brain dead production, more focused on making female characters look cool and superior than actually telling a story.
I have not read the book, but from the synopsis, it was completely different from the film. Also, it features the most rancid clichés ever: the boy who doesn't know who he is because someone sheltered him, but he's totally special because of his blood, with a wonderful all knowing mentor that dies just before they impart their wisdom and the adolescent American who can't stop and think for a single minute, doing dumb thing after dumb thing, but with a lot of people around him to tell him it wasn't his fault and finding excuses for him, because feelings.
The ending was the worst part, though. After failing miserably in doing ANYTHING, the hero finds in himself - without any effort, really - the one thing he has to do to defeat the evil overpowered opponent. A stroke of luck, followed by a lot of boasting about how he saved the day.
The story was beyond childish. Just think for any amount of time at anything in the film and it either makes no sense or it completely invalidates what it supposedly indicating. The cast was criminally underused. There are basically four characters with actual roles, Michelle Yeoh stealing the show, even with the sorry dialogue they gave her, with the others having a few lines each. I think Patrick Gallagher just says something about slobbering shower, once! The pacing was all over the place, with everything either feeling rushed or glacial. Even the editing, which should be quite fixed and done before any other work starts in animation, was poor.
I had to end the review because I felt like I had to remove stars the more I thought about it. They just appropriated (badly) elements of Chinese culture, turned them into a show even 7 year-olds would probably find nonsensical, then released them as a feature film that cost 300 million dollars. How is that even possible?
Bottom line: stupid.