Grisha trilogy

Orphaned by the Border Wars, Alina Starkov is taken from obscurity and her only friend, Mal, to become the protegé of the mysterious Darkling, who trains her to join the magical elite in the belief that she is the Sun Summoner, who can destroy the monsters of the Fold.

"The Darkling rules Ravka from his shadow throne. Alina forges new alliances as she and Mal search for Morozova's last amplifier. But as she begins to unravel the Darkling's secrets, she reveals a past that alters her understanding of the bond they share and the power she wields"--Provided by publisher.