Enna Burning by Shannon Hale
This book is a sequel to The Goose Girl, a fairy tale retelling that I enjoyed a couple years ago. Its protagonist is Enna, the best friend of Isi, the princess from that book. It’s rather dark and violent; there’s a war going on, and Enna is a key participant. She develops a magical talent for controlling fire, which she uses to aid her country in battle, until she is captured. There is a creepy Stockholm syndrome sequence, and then she escapes. Enna faces lots of guilt and some tough moral questions about her involvement in battles and sabotage, as well as her brief time as a brainwashed turncoat. The ending is almost unbelievably sunny compared with all this turmoil, and Enna’s friend Isi is almost too perfect, so forgiving and sweet. The writing is often overdramatic, but otherwise decent.