Forged - The Golden Trilogy, #4

Goldilocks was innocent once, but her cousin's plan to turn her into a killer has changed that. Before Lowell sent Auluria on a mission for his master plan of destruction, before Shadoe trained her to be a vicious and deceptive fighter, before she ever met Dov Baer and his family, Auluria was a young girl merely trying to survive. When Auluria is brought into Lowell's fold after the death of her aunt, she's placed under the supervision of Shadoe, a cruel and careless mentor to teach her to be a weapon in her cousin's war.
As her training continues, she finds herself in growingly dangerous situations, all leading to her greatest mission yet: to destroy Dov and Berwyn Baer and become the deceptive fighter that no one will survive.