Yumi and the Nightmare Painter is a delightful piece of cozy escapism that highlights Brandon Sanderson's strengths as an author. With this whimsical novel, he brings together exceptional character work, unparalleled worldbuilding for not one but two completely different settings, two distinct magic systems that work with the same artistic theme, and a solidly structured plot. The dual protagonists, Yumi and Nikaro, each stand out as unique and realistic characters who don't fit into the usual conventions for lead fantasy characters. I had such a great time following them through their shared journey as mysterious circumstances connected them to each other and literally forced each of them to walk in the other's shoes.

This novel is exceptionally well-timed for two reasons. First, it aligns with the intensifying conversation around AI and the impact it has on different art forms. Second, it fits solidly within the cozy fantasy trend that has become more popular within the last year. While Yumi and Nikaro are technically dealing with a life-or-death situation, the tone and the overall themes are still pretty wholesome. Even when the story reaches its darkest points, the overall stakes never feel genuinely high with the most significant issues in question being the individual character arcs of the two protagonists and the relationships they develop. There is a plot and two unique settings to explore, but those are secondary. This is a refreshing departure from the grim-dark trend that had taken over fantasy for several years. There will likely come a time when the pendulum swings back the other way. But right now, Yumi and the Nightmare Painter is the exact type of escapism that many need.

My only complaint about the novel is the narrator. As part of Sanderson's Cosmere series, this book takes place on one of the planets in that universe. To tell the story, he frames it through the POV of a recurring character who can be found as a minor character in other works. Since I'm not particularly attached to that character, it was a little annoying that the book was framed through his perspective rather than through a character more closely tied to Yumi and Nikaro. Design could have easily been the narrator instead, which would have achieved the same purpose since she knew and interacted with the main characters as an actual participant in the story while also connecting the book to the broader Cosmere. As annoying as that was, it wasn't enough to detract from my overall enjoyment of the novel. 
Yumi and the Nightmare Painter was a solid five-star read and easily the strongest of the currently published secret novels.