Gavin Guile is technically still the Prism, but unfortunately he is not capable of fulfilling the needs of his office in any way. Once the most powerful man alive he now finds himself an oar slave aboard a galley out at sea and even if he were to find a way to escape it really wouldn't matter much. After all he can no longer draft any color of magic after being stabbed with the Blinding Knife for a second time and what value is a Prism that can't draft? None at all which means he isn't even a valuable hostage. Things can't really get any worse for Gavin Guile at this point can they? Oh yes indeed, they most certainly can...
The Broken Eye - middle book of the Lightbringer series