Okay, I've heard a lot of people complaining about how they don't know how to write fight scenes. Well, on most forums that discuss fanfiction, it's a common thing holding some writers back. While I'm not entirely sure if it's just the descriptions or the act of fighting itself that they have trouble with, I've created this as a universal guide for fighting.
Part 1. Terms
Punch - The character balls their hand up into a fist and lashes out at their opponent. The thumb should always be tucked ON TOP of the fingers, NEVER UNDERNEATH unless you want to dislocate or break said thumb. Some dirty fighting styles teach you to keep the thumb up like you're going to give a thumbs up, as it can gouge flesh or damage eyes, but this style is illegal in almost all fighting tournaments and is considered an overall dirty move that no respectable fighter should ever need to use.
Dodging - As my martial arts teacher likes to tell beginners, "The best way to take a hit is to not be there." This means that dodging a hit is ALWAYS preferable to taking the blow, regardless of what others might say about you. It's might be nice being called a "Tough Guy", but it's better to be called a "Wimp who has all his teeth".
Block - Blocking is the act of moving an arm or a leg to intercept an attack, lessening the damage before it can deal more significant damage to the main body. Akido is an art based primarily around blocking. Blocking can often create openings in the opponent's guard, allowing for a powerful retaliation. Blocking should be done if dodging isn't as viable or even possible (such as against faster opponents). Blocking can even include advanced martial arts techniques, like tightening the skin to rock or steel-like hardness, but this generally takes ten to fifteen years of intense training.
Break - When two fighters separate enough that they're outside of the other's immediate striking distance, this is known as a break. Fighters who are worse off (tired, hard-pressed, losing) will seek to gain a break whenever possible, as will fighters who find themselves equally matched. Confident fighters will allow these breaks, but arrogant fighters will as well.
Any fighter who likes to press the advantage (cruel, visceral and/or blood-thirsty fighters) will not allow their opponents to gain a break unless they have no choice (i.e. they're forcibly moved away or downed long enough that their opponent can get one), though they too will seek one if they're being overwhelmed.
Driving Attacks - The point of driving attacks isn't hurting the opponent, but rather, gaining a distance for a break. This can be as basic as pushing the opponent back, or as elaborate as placing one's foot against the opponent and kicking them.
Spinning Attacks - The point of spinning attacks isn't to look silly, but rather to add kinetic damage.
Throws - Throws are very common in martial arts, as their effectiveness is rather high against those not nimble enough to perform aerial recoveries. In essence, a throw turns an opponent's body against themselves, as the kinetic force of the throw, gravity and their own weight combine to deal a lot of damage to the entire body at once.
Grabs - It may seem dumb to list grabbing someone, but a grab is very important. It can allow for a defense breaking kick or punch, be turned into a throw or hold or even be pressed to cause damage of it's own. Grabbing the throat, for example, can lead to a chokeslam, a rising chokehold, or rapid beatdown with punches or kicks to the exposed body (if the target grabs at the arm, which is actually a psychological response). Grabbing the legs or arms can lead to a number of VERY painful throws or equally painful holds.
Holds - Holds are VERY popular in wrestling, as it forces the opponent's body into a position that is very painful. Holds are also used when a fighter wants to control his enemy, as they often put the victim into a submissive state, allowing the fighter to either verbally calm or painfully subdue the target. Holds can sometimes lead to dislocations if the victim or fighter isn't careful or if the fighter presses them too hard.
Subdual Damage - Some attacks don't eat away at hit points or simply harm the flesh (or scale) of their intended target, they do internal damage, damaging, rupturing, crushing or breaking organs or bones, or they might just damage nerves, causing excessive pain.
Subdual damage is when muscles, bones, or organs take damage that isn't apparent, but felt by the target. Another good example is Ranma 1/2's liberal use of shiatsu points, which are strikes to parts of the nervous system that activate various automated reactions, which can include, but are not limited to: falling asleep, relaxing, tensing up, the skin growing hypersensitive, the skin becoming unsensitive, and perhaps even going poo in one's drawers.
It's often subdual damage that causes a fighter to faint.
"Guard" - This isn't about actual blocking, but rather the state when a person who expects an attack, and is ready to either dodge or block that attack. If you are surrounded by those you consider friends, you're going to be more relaxed than you are around an enemy (or even someone you just don't like). Trained personnel or martial artists often keep their guard up when they are in places they don't know or with people that they don't entirely trust. This is a careful level of preparation which isn't always visible, but the person is ready for attacks that aren't obvious. This is often shown when a character seemingly nonchalantly blocks or dodges an attack. Their guard was up, so they knew to they had to be ready to move quickly. It's considered a universally bad idea to ever drop one's guard, but it's considered even worse if one has a lot of enemies. Some martial artists never truly drop their guard.
A good example of how big a difference one's "guard" makes, is the so-called "Magic Stomach Punch". A lot of people may mock the "magic stomach punch" that automatically knocks out some characters in fighting anime, yet a few minutes later, the user receives an identical attack, yet doesn't faint.
What they don't realize is that there is a MASSIVE difference between a person ready for combat and a person having a conversation.
A person who's prepped their bodies for combat has, even if it doesn't seem noticeable, informed their body to prerelease adrenalaine, beta-endorphins (which numb pain), tighten muscles and prepare for damage. They also oxygenate their blood more than usual (this is usually only shown as the ever-so-dramatic deep breath before the fight begins).
These critical yet unnoticed actions can determine whether even an experienced fighter is coldcocked in a bar fight or if they manage to remain standing long enough to return the favor; or in the case of our "magic stomach punch", whether the victim will stay standing or faint. And that's neglecting the fact that the strike itself is already quite damaging, as it hits the diaphram (the muscle that you use to inhale and exhale), causing the victim's lungs to suddenly exhale. Such sudden loss of oxygen is well known for causing blackouts.
The difference is so huge that one can liken a combat-ready body to a T-74 Russian Battle Tank while the non-combat body is likened to a 9-Volt remote control car. The difference in how much damage they can take is nearly mind-boggling. A martial arts teacher of mine liked to recite a story of a marine friend of his who got coldcocked stepping out of a hotel. The thief had his wallet and was gone before the marine recovered. And anyone who's ever seen a real U.S. Marine knows that they are among the toughest sonovabitches anyone will ever face in a fight (outside of master martial artists and comic book characters).
Ki/Qi/Chi/Life Force/etc. - This refers to one's spirit. The most common names are Ki or Chi, but I prefer the word 'Ki', so we'll be using that. This is that undeterminable force that allows fighters to amplify their strength, speed, agility, etc. or even allow them to use moves that would otherwise be impossible. Most humans never learn to consciously use their ki, but many can access it instinctively in extreme moments. Those who do learn to use it can vary greatly.
Unlike how it's portrayed in video games, learning to project ki is not easy. In fact, a great deal of martial artists will struggle with it, and there's a good portion that will never succeed in projection. This does NOT mean that their ki potential cannot match or exceed those who do learn to project their ki, but it does indicate a self-imposed psychological or spiritual restraint. Also, unlike in video games, where things are set up to balance out, a strong enough ki user can deflect or reflect ki projectiles. Of all of the martial arts video games dealing with this, King of Fighters happens to have the largest number of ki users who cannot project their ki.
Depending on how the user learns to access their ki, manifesting ki can sometimes take on elemental form, such as a fireball, a bolt of electricity or even a wave of ice. But ki can also be used to turn the user into a projectile, like (from Street Fighter 2) Blanka's Cannonball, Cammy's Drill Kick or even M. Bison's infamous Psycho Driver.
Part 2. Attacks
Part 3. Defenses
Part 4. Special Moves
Part 5. Super Moves