Raven Stratagem
What if a human civilization with a repressive class system organized around a religious calendar was fighting a mutated branch of humanity that made the biologicals in the Southern Reach trilogy look like puppy dogs and unicorns? Hmm, then you might break out the stored consciousness of one of your most successful, but clearly insane, generals who has been dead for 400 years. Raven Stratagemis the second book in the world building trilogy started by Ninefox Gambitand ending with this year's Revenant Gun. The Machineries of Empire series needs to be read in order, with the first one much more on action, the second one much more on ruminations. But the ruminations do lead to a touching subplot with robot servitors. Ninefox Gambit and Raven Stratagem were both Hugo nominees and worth reading despite the robot cameos.