This book had a lot of battle in it and for most readers it may take reading more than once to catch all the details of what happened to every cat. Without giving anything specific away, there were a lot of deaths, many of them permanent (in the sense that the cats spirits were killed). I'd like to think that these cats might have another place they can exist, but that doesn't seem to be what Vicky or the other Erins intend. I find this part of the world created for Warriors to be a bit too final, especially since my favorite Star Clan cat was killed. I think they should at least be able to be reborn as other cats somehow rather than just winking out of existence completely even if nobody knows which cats they are. I suppose that's possible, and I'd rather thing that he or she (not giving anything away) would be able to have a life as another cat somehow even if they could never remember who they were. It would be nice if Vicky or the other Erins would allow that as a possibility.
Younger readers might find some of the battles disturbing because of the deaths involved of beloved characters. This is definitely a book for older Warriors fans.
There were things I liked about this book including an exciting confrontation between Firestar and Tigerstar, The powers of the three being used to protect the Clans, the finding of the fourth cat, which was both surprising to me, and very satisfying as to who it was. I also liked how many of the relationship problems between various characters were dealt with in the novel. Leafpool and her kits deal with their relationship problems, Squirrelflight and Brambleclaw deal with theirs, even Crowfeather discusses his feelings about Breezepelt and his other kits, and also his feelings about Leafpool. Leafpool's status as medicine cat or warrior is discussed, and Cinderheart chooses her destiny.
Even though there were some parts that made me very sad such as my favorite cat's spirit apparently being annihilated, which I don't think he or she deserved in any way, overall I found this to be a satisfying and well-written novel well worth the read.
I wish instead of focusing on series about dogs and bears that the Erins would do more Warriors. I would love to see a series that follows this one even though this seems to be a good ending if indeed it is an ending.