The opening of this was the strongest part from me, and unfortunately it was all down hill from there. 

I was extremely close to tears finding out that Gansey knew all along he was going to die. BUT then it was never even mentioned again?? Blue had been agonising the whole series about whether she should tell him, and we never even get a conversation between them where she finds out that he knows? Instead, we’re just left to assume she knows that he knows, and all the emotional weight of that really strong opening was completely lost. 

And ‘completely lost’ is a good description for the rest of the book, as well as ‘what was the fucking point of anyone of it?’. NOTHING from the past three books, or even most of this one, seemed to have any relevance to the ending. All of the Glendower stuff = pointless. The group of friends even being together = pointless (because without each of their nonsense's combining, there wouldn't have been an issue in the first place). Blue’s family involvement = pointless. Orphan kid = pointless. Greenmantle being involved again = pointless. Henry = pointless (and maybe purely a diversity hire if Stiefvater was getting flack for the lack of diversity). Angst over Gansy dying = pointless. Declan = pointless. The whole fucking book = pointless. 

The ending was also so horrifically muddled, with so many threads that never properly came together or explained/resolved. Pfff.