Black Prism - Brent Weeks

Black Prism by Brent Weeks is a gripping fantasy novel that unfolds in a world where magic is harnessed through the manipulation of light spectrum colors. The story follows Gavin Guile, the most powerful man alive and a legendary figure known as the Prism. As political intrigue and looming war threaten his realm, Gavin must confront dark secrets and personal sacrifices to maintain peace.