As far as the story itself, think of the Revolutionary War mixed with a unique magic system, gods, and cave lions. Don't forget about the cave lions. There are uprisings, downfalls, investigations, wars, and LOTS of black powder. The characters are some of the most fleshed out I have seen and there wasn't one that stood out more than another. Each one had their own influences, decisions to be made, and lives to protect and McClellan did a wonderful job bringing them all together. I really enjoyed the magic system that was inserted here, with the 'powder mages' ability to basically sniff black powder to gain heightened capabilities, the ability to direct bullets once shot, and the ability to blow up other mages' powder charges.
Overall, this was a fantastic debut by McLellan and I hate that I waited so long to give it a read.
I can't leave this review without talking about Christian Rodska. His narration was superb, even if I had to increase the speed with which I listened as he does read at a slow pace. Each character had their own unique voice inflection so you could easily pick out who was talking. Not only that, but he really gets into the body and soul of each character, acting out the dialogue instead of just reading the words. I cannot wait to listen to the rest of this series, as well as the rest of Sins of Empire, just to hear Rodska do what he does best.
You can purchase Promise of Blood over at Amazon