I liked this ending to Wren & Oak’s story, for the most part. I loved that Jude and Cardan became parts of it. I think they really act as Oak’s surrogate parents more than Maddoc and Oriana. The High King & Queen continued to watch out for Oak & help him grow as a person and kept him safe. Whereas Oriana & Maddoc acted like teachers early on, but never finished any of their teachings . 
I think parts of the story were a bit underdeveloped. It just didn’t have the same magic as the first trilogy. And I don’t think Wren grew into her own. She grew into someone else. She lost the soft parts that made her character so great in “The Stolen Heir”. She hardened almost too much. In the end, I wasn’t really rooting for her and Oak. It felt more like Wren was a learning experience for him rather than endgame. 

I think the redeeming part of the story was Oak’s growth, understanding of his power,  finding who he truly loves in his life & how to tell the difference. I think Jack of the Lakes was a fun character & I also thoroughly enjoyed Hyacinthe’s growth as well.