This one jumps right into the story and gets right into the action, with little buildup, which is a big plus. A self-confident heroine who has her world, quite literally, shaken apart, so she spends the rest of the story just trying to walk on quicksand, and a hero who is quite the epitome of glorious bastard.
If any storyline invited deus ex machina, considering this one literally begins with a literal act of god, there's surprisingly little of it. And while our heroine is often blind to what's going on, it's not because she's not paying attention or the usual reasons, it's because the people who know are purposefully doing their best to keep her that way. So for me, the dialogue hit the right note, not mountains of exposition, it's limited to things people might actually say. That was a relief (I see some other reviewers complained about that: I am writing them off as unsophisticated.) And there's none of the usual info-dumps outside of the dialogue, which takes a deft touch to pull off - we know as much as Kali knows, and not a bit more, as it should be. It also shows off the rather spectacularly well done worldbuilding - this is a post-apocalyptic ruined world that feels visceral and real.
I thought there was a distinct lack of insta-love. There's insta-attraction maybe, but also I thought pretty natural reactions to events and actions by the heroine. It's hard to say what our hero considers natural reactions, but he's got his own issues. FWIW, the idea that adults might have consenting (fade to black) even while having good reason to loathe each other, isn't a massive reach for me. When everything around you has been destroyed, I imagine one takes ones life-affirming moments where one finds them. Kali's emotions and reactions are skewed all over the place for most of the middle of the book, but that makes complete sense, given her situation. She's half on autopilot, trying to survive, and it's no wonder she's way off pitch emotionally.
I have two smallish (tiny!) complaints: One is Tiamat's name: Tiamat is firmly ensconced in my brain as a babylonian goddess, so that took me right out of the story more than once. I was half waiting for Erishkigal to show up too (maybe she can be boss of Achaia? :) As a complaint, that is a mild one, and I was over it by a third of the way into the book, this Tiamat is most definitely not that Tiamat. The other is a tendency shared by a million and one books: there's a couple too many situations of "We need to talk" -> "I know" -> "Ok, so let's do that, later" followed by the characters being alone together for several more hours (ie pages) before the promised conversation. Sometimes it's clear Tiamat is just stringing Kali along with a promise of answers, in order to get her to do as she's told, but once or twice it almost comes off as if he can't physically manage walking and talking simultaneously.
Oh and before I forget, I love the little touches of humour (the biodegradable soap made me snicker out loud) and that they aren't overdone.Overall, a solid 4, and I'm looking very much forward to more.
Disclosure: I won this book in a GR giveaway. I don't believe it affects my opinion however, I'd pay for it in a heartbeat, and I'll happily buy any sequels.(ETA to fix braindead flu-induced typo where I missed out half a sentence)