[This is a post in my series on how to write fight scenes. Other installments may be found under the tag.]
All right, enough vague philosophizing. Let's start digging into the practicalities.
For my money, the most important question you should ask yourself in writing a fight scenes is, What is the purpose of this fight?
"Who is involved in this fight?" is also a critically important question, and we'll get to that soon enough. But the who is a matter for inside the story, whereas the purpose is a matter for both within and without.
Inside the story, we're asking why these characters are fighting. What's their impetus for doing so, and what do they hope to accomplish? Outside, we're asking what the fight is supposed to do for the story as a whole. As we discussed last time, there should ideally be more than one answer to that latter question.
In The Princess Bride, there's a lengthy swordfight between Inigo Montoya and the Man in Black (whose identity is, at that point in the narrative, unknown) atop the Cliffs of Insanity. If you need a refresher on this scene, go grab your DVD; we'll wait until you get back.
Done? Okay. So, in-character purpose first.
Inigo's primary goal is to stop the Man in Black from pursuing Vizzini et al. The likely method of accomplishing this is to kill his opponent ("You seem a decent fellow. I hate to kill you.") Pretty straightforward. But there's a secondary purpose -- clearer in the book, but still visible in the movie -- which is that Inigo wants a challenge. He is, so far as he knows, the best swordsman in the world; it's been so long since he met a worthy opponent that he's gotten in the habit of dueling left-handed, just to make things more interesting for himself. So Inigo wants to win . . . but not too easily.
The Man in Black's purpose is largely unclear at that moment in the story, beyond the fact that he's obviously pursuing Vizzini, and therefore wants to get past Inigo. With the benefit of hindsight, we know he's trying to retrieve Buttercup from her kidnappers, because he's still in love with her and wants to find out whether she still loves him. He doesn't seem particularly motivated to kill Inigo, though: his response to the line quoted above is "You seem a decent fellow. I hate to die." When he gets the chance to strike, he claims "I would as soon destroy a stained-glass window as an artist like yourself," and clubs Inigo into unconsciousness. The only person he seems to want to kill is Vizzini, and that might just be an artifact of the format they choose for their confrontation.
Interestingly, he also decides to fight left-handed, against his natural inclination. Why? Not for the same reason as Inigo. Not for any visible reason at all, really -- until we look to the external purpose of the scene.
William Goldman, who wrote both the book and the film based on it, clearly wants to throw some obstacles into his hero's path. A whole series of them, in fact, which aren't just there to fill time; they also neatly demonstrate the various talents Westley has picked up in his years as the Dread Pirate Roberts' valet and eventual successor. So, this scene is here to show us he's a brilliant swordsman. (A skill which, oddly enough, he doesn't really use for the remainder of the story, although there are moments where the threat of using it is important.)
For us to understand that Westley is a brilliant swordsman, we need his opponent to also be impressive. The chatter between the two early on establishes that they both know their shit on an intellectual level, and the work they do while chatting demonstrates its practical application. But we the audience also know Inigo's fighting with a handicap (and still expects to win), so the fact that his survival depends on him switching to his dominant hand? Tells us this guy in black is pretty damn good. And then they get up to that wall, and Inigo's winning . . . .
Where we discover the Man in Black was also fighting with his off hand.
It has less to do with his own purpose, and more to do with the writer's purpose in crafting the scene. Aside from being a dramatic reveal, a charming bit of parallelism, and a moment to subdivide the very long fight (that's something we'll talk about more later), it hammers home the fact that Westley is just that badass. Inigo, who's been set up as the consummate swordsman, has finally met his match.
(We should pause here to note that in many cases, it's a bad idea to have the only (apparent) reason for something be external to the story. "Because the author needed him to" is not a satisfactory answer to the question of "why did the hero do that?" It works here because the story already has its tongue planted pretty firmly in its cheek, and also because it isn't inconsistent with Westley's character.)
That's how I analyze the fight, anyway. I don't actually know what was in Goldman's head. So let me talk briefly about one of my own scenes. I don't claim it's brilliant stuff -- hell, I was nineteen when I wrote it -- but at least I know why it goes the way it does.
In Warrior (formerly known as Doppelganger), there's a scene where Mirage, one of the protagonists, gets jumped by a group of four Thornbloods. Externally, the reason for it is mostly plot: Mirage needs to get captured, so she can have a Very Important Encounter not long after. But I also wanted a chance to demonstrate something important to the story, which is that Mirage, for reasons of her nature, is gifted at combat beyond the norm. There are a few fights earlier in the story, but they're largely brief and against people who don't pose much of a challenge; the semi-exception, a scuffle with the assassin she's chasing, isn't a big set-piece either. (That comes later in the story.) So by putting Mirage against four highly trained opponents, I got a chance to really flex her muscles, so to speak.
Internally, there are of course two sides, Mirage and her opponents. Her goal, as I conceived of it, is primarily to get away. Four-to-one may be normal movie odds, but it's pretty bad in real life, and so her best bet is to escape. In pursuit of that, she is willing to kill, maim, or otherwise incapacitate them in any way she can, while trying to get to a door. The Thornbloods, by contrast, have been told to bring her in alive. This handicaps them in multiple ways: they show up with staves and bare hands, rather than the blades they'd rather be using; they can't risk injury that might kill her; and they can't let her escape. Furthermore, there's a character detail in that the group is being led by a woman who really detests Mirage. She's masked, so Mirage doesn't know it's her until the fight is over, but it does color the way I conceived of and wrote the scene.
Why does the question of purpose matter? On the internal level, it determines what the characters are willing and unwilling to do. You probably won't kill your best friend if the goal is just to make her give back the diary she stole from your dresser; on the other hand, if the guy you're fighting murdered your entire family and you want him to pay? Very few holds barred, there. On the external level, it determines how you put the fight on the page, and how it will end. Mirage's need to escape and not get surrounded meant the fight would be very kinetic, moving all over the room; the handicap on the Thornbloods meant she wouldn't be permanently hurt; the plot reason behind the whole thing meant it would end with her being captured; and the desire to show off Mirage's skills meant the whole thing got a fair bit of page time (about four pages all told).
Know why you're doing this fight. Know why your characters are doing it, too. Having to articulate those answers to yourself may give you interesting ideas for how it should go, or make you rethink why you're bothering in the first place. "Because it would be cool" is not inherently a bad answer -- that's at least partially the answer behind every fight scene I write -- but it probably shouldn't be the only one, unless you know you're writing for the sort of audience that will eat it up.
Feel free to discuss other examples (your own work included) in comments. The tension between the different purposes can be really fun to explore.