Perhaps 3.5 ... ? 
 There was a point when this book was a 4 star book for me. This ended at one vital point (and I'm not sure if this is a spoiler or not) : (view spoiler)[ when the magic is introduced, and of course Celaena is THE most important. What a shocker ! Seriously though, the magic did seem a bit too much, although if Mass MUST have introduced it into the storyline, surely there is a better - smoother - way of doing so ? Also, the way that the king turned out to have KNOWN all of this power all along seems odd ... like the entire build up of his character seems to be the epitome of power hungry asshole ... if he has access to this power why would he not use it ? Perhaps this is explained in later books, but as it stands ... hmm ... (hide spoiler)] 
 I enjoyed the characters. Dorian and Chaol were both good so far, and I didn't particularly mind the love triangle (then again, I'm not particularly against them like a lot of people seem to be?) However, I did notice these possible romances set up EXTREMELY early on in the book which seemed a bit dumb, especially as our assassin Celaena should surely have more guard than that, given her past ...? I also really liked Nehemia and I am glad that she actually turned out to be a good nice woman ! I was expecting her to be another bitch (what happens in a lot of books with women unfortunately ...) but no ! Of the more minor characters I also liked Kaltain, and I'm hoping that there is more character development of her later on in the series, and I hope that we get to meet Nox again later on because I also liked him. 
 What I didn't like was Cain, he seemed pretty ridiculous as a villain, overall, and made completely out of proportion and over the top honestly ... 
 Reading this, I find that I am glad I read the Assassin's Blade before this, because I would have disliked Celaena a lot otherwise, I feel. But after reading the prequels I didn't mind her so much, though some of the stuff she did seemed very stupid and not assassin like e.g. eating those sweets that just randomly appeared in her room, not waking up with Dorian being so extremely close to her ... like what the hell !? An assassin who had been enslaved in salt mines would surely have more sense and caution than that ? The way that she acted some of the time was good I guess as she was not a perfect character, she seemed to have some flaws and actually seem extremely childish (e.g. biting the pool cue when she is not successful at pool) and I did enjoy this, though I wish it also translated a bit more to her abilities ! I also liked how the impact of her time in slavery was shown (bit of trauma, being sick after eating, not as fit as she was) because it would be annoying if she came out and was completely perfectly fine (though there was a little bit of this). I think her character COULD be developed well and I could grow to like her more in the next books ? 
 Overall I generally enjoyed it as a quick and easy read, though I did have to suspend my disbelief at points. I am also eternally grateful that when Celaena and one of the boys kissed, he didn't growl like Sam seemed to do in the Assassin's Blade because that seemed ... really weird.