Renegades by Marissa Meyer

The Renegades are a syndicate of prodigies―humans with extraordinary abilities – who emerged from the ruins of a crumbled society and established peace and order where chaos reigned. As champions of justice, they remain a symbol of hope and courage to everyone . . . except the villains they once overthrew.

Nova has a reason to hate the Renegades, and she is on a mission for vengeance. As she gets closer to her target, she meets Adrian, a Renegade boy who believes in justice―and in Nova. But Nova’s allegiance is to a villain who has the power to end them both.