The raptor sent me a link to this blog today which looks at some of the challenges of writing fantasy battles, and whether you should even bother. He makes some interesting points, including one about telling rather than showing which set off mild alarm bells whilst at the same time sounding pretty valid. I strongly encourage you to read it.
It also made me realise how lucky I am, as a fantasy writer, to have experience in fighting in fantasy battles. Hooray for LARP. And speaking from that experience, I can tell you that as an individual you have no clue how the battle is going. Everything’s chaos and noise, and you have to concentrate fairly hard on the five guys opposite who can reach you with pointy things, whilst also trying to defend the two people either side of you AND stab the enemy. It’s pretty rare that you hear orders being shouted, and even then it’s mostly uncomplicated things like ‘hold the line’, ‘push forward’ or ‘pull back’. Also, fighting retreats? Not easy. Everyone moves at a different pace, so either the force is massively strung out and vulnerable, or bunched up and the rear guard have no room to fight or retreat in.
Magic only really makes a difference if it’s unequal – if both sides have the same sort of magic levels then it largely cancels out across the battlefield. That’s not the case for small pockets – individual units are never going to be equally matched – but it isn’t the big decider unless it’s truly dooming and the other guys don’t have any equivalent. Also, remember that magic should have limitations, otherwise you risk it becoming a deus ex. Speaking as a gamer, I like to have those limitations clearly defined so that I can make them obvious to the reader, but that’s a personal choice. In battle, magic can definitely be a cause for heightened fear in a soldier or unit of soldiers, but for the most part I think generals should see it as just another weapon of war (unless, as said, it really is a game-changer).
Anyway, like Django Wexler says in his article, if you want to write fantasy/historical battles then find a LARP or re-enactor group and ask to have a go. They’re usually very keen to share the pleasure their hobby gives them with other people, and even one battle will give you a taste for how impossible it is for a soldier to know what the hell is going on.