I really, really enjoyed Ninefox Gambit. I’m an experienced reader but I had difficulty getting into it at the beginning.
It’s about a universe where they discovered that strict adherence to holidays and calendrical events can influence reality, and allow “exotics”, or extremely powerful and weird weapons. It’s about a woman with another personality implanted in her–a traitor, but one who has never lost yet.
If I had to compare it to anything, I’d say, “Too Like the Lightning“, even though they’re extremely different.
My only complaint is that it does not feel like a complete story. The sequel is coming.