This was okay, but other similar-genre fiction I've read this year has been better.
Things I liked: the strange communication style of the Nahx. Their backstory, still unfolding- why are they humans? What's going on there.
Things I didn't like: histrionic social dynamics- the dead twin and the twin that hates Raven... the idea that Raven is just "special" and can penetrate whatever brainwashing Eighth has going on. It was a little too Bella-and-Edward for me, though I do think Raven is more of a badass with more agency.

Overall the world-building is intriguing but extremely bleak. The cliffhanger ending has me intrigued.