Okay . . . I have some thoughts. Otherwise, I probably wouldn't be writing this review. My thoughts consist mostly of the following:
1) Kiernan Kane is just about the most excellent character ever. That is absolute, objective, incontrovertible fact. It's a basic fundamental. Like the existence of iguanas.
2) This conclusion to the quadrilogy was an incredibly dynamic one, to use the phraseology of today. Unfortunately, that phraseology does not carry the weight I desire, but it's too late now.
Mostly, though: Kiernan Kane. I mean, this is an impressive character. But spoilers, so there goes any explanation.
Speaking of spoilers, all the twists and what-do-you-call-its were executed with such unwavering skill that I said to myself (though not in so many words), "Huh. That would make a pretty spoiling spoiler."
Now, let's just turn to character's in general, all right? I didn't quite hear your answer, so I'll take it as a yes (yes makes for a pretty useful noun, incidentally).
Characters. Now, don't suppose for one minute that there was Kiernan Kane the Glorious and then Generic Character A, Generic Character B, and Jane Doe, who was the embodiment of Trope II.A:32. As a matter of fact, all the characters had an impressive depth, depths that on average were comparable to that of South Pole–Aitken basin. Of particular interest are such characters as Brant, Kiernan Kane, Ina, Kaitryn, Kiernan Kane, Yole . . . actually, this is going to take a while, so just one tiny little "Kiernan Kane," and then I'll stop. Kiernan Kane. Stop. Actually, Brant and the rest of the above are particularly charming characters, too. For that reason, if I'm not careful and I continue writing about all this, I'm going to end up in what we programming types call an "infinite loop" – and those are miserable.
I'm not really going to explain the ends and outs of why the characters are well worth reading, but they're very well developed. There. Hopefully, you're satisfied.
"But surely this book started off badly?" you protest if you are pessimistic like that, hoping to stop me in my tracks before I continue spouting praise.
"Nope," I reply. "Great beginning, actually."
So much for your attempt.
Now—setting. This is just exactly the type of setting that deserves about two dozen people to dedicate a full twelve hours to periodically saying "Capital! Capital!" about it. It has dragons, which is pretty much enough. But it also has all the other good stuff like swords made out of dragon teeth archipelagos of a sort and staves and stuff like that. I am heartily fond of a staff. Oddly enough, @ReconditeStaff is my Twitter handle, and that has to tell you something. The book, furthermore, has richly composed kingdoms and corridors (and a Corridor, if you know what I mean).
By the way, every chapter begins with some excerpt or quote from the world and that's something that definitely needs to be done more in books.
"Was the plot—?" you might begin to ask.
"Yes," I reply helpfully because you were about to ask if it was worth anything, pretty much.
Okay, okay. I'll say a bit more; however, I don't want to spoil anything. The plot is one of those that have separate things going on but it's all doing the same thing, so the things all come together, and the thing happens. It's excellent, and it might do your joints good to read it – you never know. And it has Kiernan Kane and Brant and—et cetera.
Yes, I am aware such as the above isn't too helpful, but I honestly amn't very fussed about that fact.
Oh, this book also had its funny parts. There's something in its favor.
Now, I'm tired of this review, and, really, you already ought to be thrilled about this book because of my concise and detailed exposition of its merits in the character, plot, and worldbuilding departments, but, unfortunately, it is my habit to say something about the writing.
The writing wasn't half bad, to put it mildly. (Reaching the end of a review makes a person want to put things mildly.)
There. I'm done. Good.