This was not great. 
I need to stop expecting sequels to give me what was lacking in the first book. The fourth wing was good and this was slightly less good. 
It was nice that it began right where we left off in the first book,

and I liked seeing Liam in Violet's mind throughout the book.

I liked Imogen and Sloan, and I loved that we got to see Violet interact with her mother. (Hope I spelled the names right, I listened the audiobook so I didn't see them in writing). It was refreshing that we didn't fall into the romance and have zero plot movement in the sequel, as sometimes happens with this genre. That being said, the story did lose momentum and drag a bit. 
There was no character growth and the relationships between characters were just as frustratingly under-explored as in the first book. Violet didn't seem to learn much and Xaden didn't open up any more that he was forced to. We didn't get any real backstories, and very little insight into the dragons lives. 
The end was definitely a surprise. But it wasn't a cliffhanger that leaves you wanting more, it was just kind of a wtf moment. I might read the next one when it comes out but it won't be on my tbr.