In my opinion, the book could've been a lot better. To be fair, I liked the way that the three stories seemed so far apart in the beginning, but began to intertwine into the big picture near the end, and the characters encountered each other, and I could read the account from both sides. I thought the idea of the curse was very clever, considering it was bound to the water, and since water was a vital thing to people, it made the spread of the curse more intimidating and the quest to stop the curse more urgent.
As much as the curse was cool, a few of its aspects could've been a lot less violent. For one thing, it seemed that a person died every 30-50 pages because of the curse. Also, the fact that the curse drove people to rape as well as kill was just wrong. Gladly, it wasn't descriptive about that, but it was plenty suggestive anyway.
For another thing, the development of some of the characters was a little weak. For Harkeld, his relationship with the other mages is very blunt and not smooth at all, and his relationship with Innis was very choppy, in the sense of how it grew. I really liked, though, the developement of Jaumé as he traveled with the Brothers and Bennick. It was interesting to see his decesions, and it kept you guessing which side he was on, until the very end.
To cap it all, their language was quite crude. There was a lot of sexual references and jokes that were very cringy. Also, the magic part of the book was not very well thought up. It seemed like the author was trying to pull ideas from other "magical" books but didn't totally want to plagiarise so it ended up not being a very good idea.