Enjoyed this volume more than book 2 of the trilogy. Although Fitz wanders around a fair bit, initially trying to murder Regal to avenge Shrewd and the wrongs done to Verity and co, and it does get a mite tedious that he keeps being captured and beaten etc, he does manage to get even with the minor sadists involved in beating him so badly, though more by luck than judgement. He meets some interesting characters such as Kettle, though he continues to be several steps behind the reader in seeing what is in front of his nose: the truth about Kettle, what happened to the minstrel Starling and the other women when they are all captured, for example. And there's the whole sequence when he is being questioned about Molly's whereabouts and I was mentally shouting "Don't tell him, he's been taken over!" I do get annoyed when characters are made stupid just to make the plot work. 
 Finally we discover what sacrifice Verity has made and must make to bring relief to the embattled Six Duchies. I did think that certain aspects of the book - the journey from the Mountain kingdom to find Verity, the nature of the Erlings and how they are eventually revived being a couple of examples - are very dragged out, whereas the big climax of three books and a very long story is rushed through with just a narration of Fitz's remote witness. It would have been far more satisfying if he could have taken more of a role. I know this volume in particular paints him as the Catalyst, but a real catalyst has an effect on things around it without being changed itself whereas Fitz has obviously been greatly changed throughout the trilogy, so it would not have been breaking some rule of magic to make him more active at the end. Also this book is not at all satisfying from the POV of wanting Regal to pay for his crimes, and given what else Fitz does in relation to Regal, it seems stupid that he does not at least arrange for a posthumous exoneration for himself, in case it later comes out that he is still alive.