Echo of the Evercry

I received and reviewed an ARC, but my review has not been influenced in any way by the author or publisher.

 History is not always sung by heroes. It is sometimes written by the villains who told their story first. 

Echo of the Evercry

There are a faction of knights, called to destroy the magic users who have been corrupted by power. The knights are well trained, respected (or feared), and powerful. But they also rely on their own magic users to know their enemy. But who is the enemy, really?