Writing Fight Scenes: The VIOLENT Method
okay, so because people have a hard time writing effective fight scenes, I'm going to walk everyone through the method that I use for everything from massive sci fi battles, to quick three-v-eight sword brawls to bar fights.
The VIOLENT Method. (Because fun mnemonics)
Visceral: Make sure your audience feels it by keeping it grounded in injuries and pain. People get fuckin' hurt in fights, and no fight where people do not is going to feel real. Tying into this, people don't fight fair, and people don't fight pretty. Even people who are trained fighters will make mistakes in their technique in a real fight because adrenaline makes you worse, not better, even as it makes you faster/stronger. Also, in real fights people stomp on downed opponents, take shots at turned backs, people bleed, scream, etc., Also, really critically, people are exhausted after fights. Your characters should be wrung by the time it's over, even if it only lasted for a few minutes.
Immediate: Keep sentences short and punchy. No one is analyzing every step of the fight tactically while it's happening. If characters are thinking "Ah yes I will make him overextend and then pull his wrist in and throw him before stomping his head…" I know that the author of the scene has never been in an actual fight. Keep sentences short and punchy. "Draw in, grab, and throw."
Obnoxious: Tying into the above, fights can be disorienting. Don't overdo this, you need your reader to have an idea of what's going on, but don't underdo it either - things should be a bit chaotic. If it feels like the characters know everything that's going on around them, you're doing it wrong. Read what the following sections say about rhythm, but bear this in mind: once you get a rhythm going and keep it flowing for several paragraphs: break it with a short, hard paragraph and shift it in a way deliberately disorienting to the reader on purpose to drive in that things are unpredictable. In a fight, there's a lot of noise, there's a lot of confusion, and that should reflect enough in the narration to bring a sense of it to the reader - but again, don't overdo it to the point where the reader can't tell what's going on.
Liquid: Fights flow. There's a definitive rhythm and momentum to a fight. While the characters won't necessarily have a great idea of everything happening, they WILL have a sense of the momentum around them and the way the fight is making them move. Momentum and movement are going to be the key to writing an impactful fight scene and give the reader a sense of excitement, or, if you want to give a sense of a dragging, exhausting affair of attrition, do the opposite: grind the momentum to almost nil while two massive groups start sniping and grinding at each other with almost no movement.
Environment: Where's the fight happening? How is everyone moving? Describe the surrounding environment. This is the space a fight is happening in, whether a big open field, a forest grove, a small tight room where you can use the walls for leverage, a park where you can use benches for jumping points or to smash people's heads against, etc., matters in a fight, as does how everyone is using it. Heat, cold, visibility, all of these factor into a fight as well.
Narrator: Who is your narrator in the fight? A trained soldier? A trained fighter? Just some untrained schlub who has no idea what they're doing? These people have a different idea of how fighting works, and that matters. What a soldier notices, what a correspondent notices, what a martial artist notices, etc, are all differences. Keep an eye on how you present this.
Tactics: What does everyone want out of the fight? Is one side fighting to kill the other? Just to knock out? To capture? To take a location? Just to drive each other off? What are the rules of engagement? How trained are the combatants? What kind of discipline is everyone under, if any? Weapons? These all matter when you're asking questions, and you should research what effects all of these will have, but short version: fighting to kill is easier than fighting to capture, and its very rare, despite what the movies say, that any force will fight to the last man rather than retreat.