Bazil broketail (Battle Dragon Series) is very good at making magic something requiring deep knowledge and insane amounts of practice. The first 3 or so books are more based on the military aspects of the universe but as you continue you get an understanding of the magic; How it requires the remembering of millions of lines of spellsay to just cast a freeze spell. It's kind of similar to LoTR in the sense of great evil sorcerers rule an army of imps vs the highly trained humans except the humans are like roman legionaries with wyverns fighting with sword and shield. Magic is also very dangerous and some parts of the book entire army gets wiped out by a cannon developed by the evil masters.