The Raven Tower (Fire-Walker) by Emma Miles

How much would you sacrifice to save your people? Your freedom, your home … power … love … your life?' Wild Kesta has been raised to be a leader, trusted, loved, with the freedom of her cherished Islands. When she uses the magic of the Fire-Walkers to search within the flames, the Independent Fulmer Islands seem doomed to fall. Spring brings the ruthless Borrow raiders, their attacks earlier, more ferocious, desperate. Kesta’s only hope is to strike a bargain with the King of Elden and his dangerous sorcerer, The Dark Man. Can Kesta subdue her fiery nature and work with a man she hates, a man she fears, to stop the evil necromancy that will consume their lands and make them slaves? To save her people, how much will she sacrifice? "The plot had action, twists, drama, romance, emotion ... everything that makes a great fantasy story." Jess Bookish Life