The cover says this is "a novel of Isavalta" and it takes place in the same universe, but no Isavaltans are actually mentioned. It seems to be pretty self-contained and doesn't require reading the previous Isavalta books.
This is another book that had been sitting on the shelf for a long time; in this case, because the previous Isavalta books, though good, were very long and difficult to get through, and I've kept putting off reading a book that I feared would take me weeks to get through. This one isn't so chewy. I did spend pretty much all day yesterday reading, but I got through most of it and finished it today. It's a good, exciting story of intrigue, as long as you can deal with actual gods directly and significantly intervening in mortal affairs. It also has a fairly interesting approach to magic, although we don't get exposed to as much discussion of how magic works as we did in the first couple of Isavalta books. And it's a fairly satisfying story of how real people can become corrupted and become villains, and of betrayal and commitment. It's a good read, but I don't think it reaches great. So 8 out of 10. (I am concerned that I'm giving that rating to an awful lot of books these days.)
Bleah. If I write a plot summary I'll be late to bed, so it needs to be skipped.