The sequel to AetherBorn picks up essentially where the first novel left off. Ruby, now leading the Elementals and spurring the reunification of the Houses, uncovers a new threat that puts the Houses at risk.
I found this novel to be a tighter and more satisfying read than the first installment. The pacing felt much more consistent throughout the novel and was well-executed. I found the new elements of world-building to be promising, but not as clear to me as I would have liked. Having said that, these elements are likewise murky to Ruby (whose perspective the reader follows), so this is more of an observation than a criticism. (I didn't have the feeling that Ruby was misleading or unreliable in recounting her understanding of these new elements).
The character development was also much stronger in this second novel, with Ruby having grown more into her own as a character. There are some elements that I found stretched credulity (her role being universally accepted despite her age, for one thing). I also found that other main characters (particularly Liam) read as flat to me. I think there's a lot of potential to develop the other important people in Ruby's life into rich characters, and that wasn't realised for me.
When the villain is revealed, I found it to be a let-down. This character also had the potential to be complex and interesting, and I didn't feel that this was achieved.
The editing is the one element that I found lacked more in the second novel than the first. There were problems with verb tense, possessives, and incorrect words being used (yield instead of wield, for example). I think another pass would really help tidy this up.
Overall, I do enjoy the story, and I think there are some unique elements in the way the universe works. I look forward to continuing on in the series.