This movie is a prequel for the King's Avatar anime. Even though it is a prequel, only a very limited number of the characters appear in the actual anime and you don't require much knowledge so you could watch it as a standalone movie if you wish. Still it would probably be better to watch the first season of the anime first so you have more of an idea of what the movie is about. The movie was not bad but I feel like it lacks coherence. The story has a lot of neat emotional moments yet those moments aren't connected very well or arenot set up as well as they could have been which lessens their impact. Aside from these moments I wasn't very impressed by the story but it's not like it was horrible either.

The art had a similar absence of coherence. Some scenes are beautiful, some scenes are okay and some scenes are cgi crowds. The lack of coherence here isn't a bad thing per se. The animators did a good job identifying the more important and cooler scenes and spent more time animating those and less time animating less interesting things. Overall this is okay but there are some scenes where there is a weird dissonance between art styles which can be a bit jarring.

From my point of view the main reason to watch this movie is to see more of the background of the main character and how he ended up where he ended up in the first place. You also learn about what relationship he has with one or two side characters. It was neat to see a bit of Ye Qiu's origin and I think it'll make watching future seasons more fun.

Overall I recommend this movie to anyone who is interested in the character and interested in watching the King's Avatar. For anyone who is looking for a good story or good animation it's a bit more hit or miss.