A Riddle in Ruby: The Changer's Key

Ruby Teach is a prisoner.To save her friends and family, she bargained with the terrifying captain of the king's elite guard. Now she's locked away in a fortress, training to become their greatest weapon. And the guard's foremost alchemist is putting her through endless experiments to find the secret in her blood?the secret that could turn the tides of the coming war.She has no idea where her friends are. They don't know where she is.But they are desperate to rescue her. Athena, Cram, and Henry must evade mercenaries close on their trail, dangerous wild beasts, and the perils of the wilderness itself to find the one person who can locate Ruby?her mother. Yet no one has seen the mysterious, powerful woman since Ruby's birth. Time is running short. War is looming. Will this motley band of friends rescue one another, or lose everything?