Iiiiiif you haven't figured out (my user name might be a bit of a clue) I have more than a passing interest in the Aztec empire. It's a hobby, no more; I can't speak the language anywhere near as well as I'd like and it's not exactly an employable skill unless I wanted to go into history anyway. So I'll leave you a bit of history instead:
The Aztec empire had a very well-developed military, with a peasant levy and three orders of knighthood, with the Arrow Knights being a lesser order, and the Jaguar and Eagle Knights being the upper orders. Eagle Knights were very prestigious and served as heavy infantry, and the Jaguar Knights were more "spec ops", primarily concerned with solo combat, stealth, and the live capture of enemy targets of value.
While Jaguar Knight captures were probably used as sacrifices (one of them being a year-long cosplay as the god Tezcatlipoca), most of the wartime sacrifices were from war exercises called Xochiyaoyaotl ("Flower War"), where the goal was capture, not death. The Triple Alliance (the core of the Aztec Empire, based on the city-states of Tenochtitlan, Texcoco and Tlacopan) used these to deplete the manpower of rival city states over the course of some years, to be able to conquer them better.
Oh, and a trivial tidbit: The language of the Mexica, Nahuatl, is syncretic, a trait it shares with German. You can make up new words by jamming together smaller words that, together, describe the concept you wish to express. Also the pronunciation key is phonetic Spanish, since written classical Nahautl is pictographic.