** spoiler alert ** 
 Mixed feelings about this one. 
 Mostly I was confused since it's been such a long time since I read Crown of Midnight. I remember loving CoM even though I was slightly disappointed with the fae direction the book was taking. 
 Heir of Fire was a slower book by far and a bit of a filler. Having said that, I didn't put the book down and it kept my interest the whole way through, in spite of dreaded POV changes (I don't know why authors love to do this when IMO it completely slows the pace down to a crawl, and you're always going to have at least one that you're not particularly interested in). 
 My thoughts on the characters: 
 Celaena - I don't like the more frequent use of Aelin as her name. 
 Rowan - I don't know how I feel about Rowan. He's such a random (and right now seemingly pointless) addition. With not a huge amount of personality. 
 Maeve - For all the lead up to this terrifying immortal figure, the climax was disappointing and she was easily defeated (too easy for my liking). Plus I don't really get why she was included as she didn't really add anything to the story. 
 Aedion - I quite like him, but for all his traitorous and daring ways, I'm not sure what he actually achieved. Also I feel like his days are numbered. He said he only wants to see Aelin 'once' a lot of times, so will probably see her once and then get killed off. 
 Chaol - Hmmm. I wish we still had some of the chemistry back from CoM. In this book, both Celaena and Chaol seem to almost move on from each other. Also, I said this before in CoM, but I'm still baffled as to why Chaol works for the King. It's not like he's a foot soldier, he's a Captain. So surely he must know what the King does? 
 Dorian - A pathetic reversal of character. I wanted him to be practicing his magic and manipulating events, going to meetings, finding out information from his father, experiencing highly stressful and tense moments by playing dangerous political games, gaining allies etc. I wanted the relationship (even a lack of it) between father and son explored. Instead we got him falling in love with some random boring healer within a couple of pages. Am I supposed to care about this relationship? Because I didn't. Even when her head came off. 
 Sorscha - A plot device and one I wasn't too fond of. 
 King - I wish he had more description and presence. He has so much impact on Erilea but when he's in the room, he's a cutout. I want to feel the cunning, ruthlessness, and power. 
 Manon - I quite enjoyed her chapters but I'm very confused why she doesn't just take the wyverns and go claim her homeland back now rather than working for the King. I don't see what Ardalan can do if they decide to just take off with them (just like Manon did when she stole the silk from the spiders) 
 Overall I did enjoy the book, it was still a good book. I just think it could've been better. I will continue with this series.