This guide relates to soldier-level combat, whether applied to military units in Dwarf Fortress mode or the character in Adventurer mode. For organizing your troops, and managing the warfare aspect of Dwarf Fortress, see Military.
 Combat Mechanics
The attacker rolls to hit, and the defender rolls to parry, block, and/or dodge. If the attack is parried or blocked, the defender attempts a single counter-strike on the attacker. If the counter-strike is blocked, the attacker does not get a counter-counter strike.
If the attacker hits, a random location is struck. It is unclear whether each individual part of a limb (say, upper arm, lower arm, and hand) each have the same chance of being struck as the head, but due to the greater number of limbs, it is more likely to hit a limb than the torso or head. In this light, weapons with critical boost are less effective, because a leg does not have any internal organs to injure.
The amount of damage done by a weapon is affected by nine factors: weapon type, weapon material, weapon quality, weapon wear, attacker strength (presumably), the "degree of success" of the attack roll, the armor worn by the defender, and the toughness of the defender.
Weapon quality increases both damage and the user's effective skill level: each level of quality grants a 20% bonus to damage, plus one skill level. It is unknown how large these increases are for artifact weapons, but it is presumed to be much higher than masterwork weaponry.
The exact effects of armor are vague. From the numbers (70 for plate, 40 for chain, vs. about 100 damage for most weapons), we can guess that armor simply subtracts from damage.
Linking damage to the degree of success of an attack roll means that higher skill will usually deal more damage. (It's also possible that damage is linked directly to skill.)
Damage to any particular body part is cumulative; if you attack with a badly worn, wooden mace with no skill for long enough (and your blows aren't simply "glancing off"), you will eventually break somebody's arm, even if the victim thinks it feels like being slowly whipped to death by scented shoelaces. Unless, of course, it simply kills you first.
 Body Part Damage
Damage to a body part comes in six flavors:
Each weapon causes the "lightly wounded" and "moderately wounded" levels using different messages. For example, a blunt weapon causes bruises and sprains, respectively, while a sword causes cuts and bad gashes. Although these indicators tell you the condition of the body parts, they don't tell you the exact amount of health they have. (ex: A body part can still stay "lightly wounded" sometimes if hit again, if the shot doesn't simply "glance away").
Broken or mangled limbs are useless. Breaking an arm or hand will cause a creature to drop his weapon/shield, or make it unable to attack with that limb. Breaking a leg will cause a two-legged creature to fall, making his extinction much easier. (Oddly, cutting off both arms and both legs of a bipedal creature won't make them fully immobile. Maybe they crawl around with their jaws.) It also takes two broken limbs to make a 4 legged creature fall.
Lopped off limbs are gone forever. They do not grow back, even in Adventure Mode.
For further information, see Wound.
 Falling Down
In a word, don't. A creature's speed will drop to 1/3 of normal while on the ground. Useto stand up again in Adventure Mode. If the creature has a broken or mangled leg(s), or a condition that disables the legs, it cannot stand back up.
 Bleeding and Pain
In addition to body part damage, weapons also cause bleeding and pain.
Heavy bleeding has three effects: The first effect of constant heavy bleeding is that the creature will become faint; the second effect would be that the creature will become pale; lastly, if bleeding still continues, the creature will bleed to death.
Pain causes three effects, in increasing amounts: less combat effective (damage? odds of hitting? slower?) and nausea (even less effective?). If creature is under extreme pain they could also fall unconscious (give in to pain). The more toughness the creature has, the more damage they can take before giving in to pain.
 Getting Weapons Stuck
A piercing or slashing weapon can become stuck in an opponent. There are two things you can do when this happens: twist the weapon in the wound, or try to retrieve your weapon. Walking away, or pressing wrestle the weapon from your opponent, you will lose hold of it. To try again, grab the weapon (via wrestling) with a hand, and you will again have the option to regain control on the menu.and selecting your weapon (which is red) will attempt to pull the weapon from the wound. Presumably, your strength is compared to your opponent, and grasping the weapon with additional hands/limbs will improve your odds of success. If you fail to
If you attack a creature while your weapon is stuck in them, you twist the weapon: it causes additional bleeding and pain, but has no other effect (even if stuck in the head!). The advantage to twisting a weapon, on the other hand, is that you never miss. This is often the fastest way to take down a large living creature; they often have great armor, and ignore the majority of your attacks, but twisting a weapon five times will knock them unconscious with heavy bleeding. At this point, you can continue to twist your weapon to ensure death, or retrieve your weapon with no contest in order to attack other creatures. If your opponent has no blood, and is immune to pain (e.g., undead), then twisting your weapon will have no effect.
 Knock Away
Occasionally when fighting, a weapon strike will connect with enough force to propel the victim several tiles away. This is a fairly common occurrence on killing blows, but can happen during normal combat as well. That can prove to be an advantage, especially in adventure mode, since that creature will be out of commission for a short time while you deal with his friends.
Blunt weapons (maces and hammers) are supreme at causing this effect. With enough strength and a good weapon it'll be common even during normal combat, and upon killing blow, the creature may fly up to 20 tiles away. Unless there is something in the way, of course.
Swords and axes can also cause this if the weapon is of high enough quality, and the attacker is skilled enough. However, it never happens to the degree it does with blunt weaponry.
Once in the air, the victim is surrounded by a blue background to signify that is flying. It will fly at a very rapid pace until it hits an object, a creature, or the ground. If a creature is hit by the flying victim, he'll be stunned and knocked prone, but otherwise uninjured.
This can even be done by throwing weapons. It is unknown whether the chances of this happening are different from that of a melee attack with the weapon, although it is possible it relies on the throwing skill.
 Slamming Into Obstacles
If a creature is hit hard and is slammed into an obstacle (like a wall, tree, or any other stationary object), the creature may take additional bludgeoning damage as well. Falling off a cliff also counts as slamming into an obstacle.
If the victim hits an obstacle with enough force, he will blow apart and disassemble into a pile of body parts, some of which might fly a couple tiles away from the impact zone.
In adventure mode, sometimes creatures smashing into obstacles will produce the "instantly fatal" death message more than once on the same major body part.
Paralysis is a condition where a creature cannot move for a long time. It's about the same as being unconscious, but the creature is still awake, however can't feel anything (maybe). In adventure mode, time passes quickly when your adventurer is paralyzed.
Paralysis can be caused by being poisoned or by severe brain damage (which may lead to permanent paralysis).
 Skill Modifiers
The combat skills are modified by dynamic events. The following algorithm seems to be used (please note that some creatures are unaffected by some modifiers):
- get the appropriate combat skill level
- if the creature is nauseous, divide by two
- if the creature is drowning, divide by two
- if the creature is stunned, divide by two
- if unknown test, divide by four
- if pain > 100, divide by two
- exhaustion* - choose 1 of:
- if exhaustion >= 2000, lvl = lvl x 3/4 (75%)
- if exhaustion >= 4000, lvl = lvl x 9/16 (56%)
- if exhaustion >= 6000, lvl = lvl x 27/64 (42%)
- if thirst >= 25000, divide by two
- if hunger >= 50000, divide by two
- if drowsiness >= 57600, divide by two
- (* re exhaustion: each "step" is 3/4 of the previous - for example, a creature with exhaustion = 6500 has a new level = level x 3/4 x 3/4 x 3/4)
 Weapon Analysis
 Bows and Crossbows
These weapons have a significant critical boost (single attacks have been seen to injure 3 different organs), but their main advantage is that they have range. Much as the common availability of rifles allowed every soldier to attack simultaneously in real life (as opposed to merely the front rank of a unit actually attacking the enemy), a legion of bowmen will all strike at once. The poor performance of both crossbows, and especially bows, in close combat suggests that ranged soldiers are better with a "skirmish screen" of melee troops.
The effectiveness of ranged weapons is greatly affected by the geometry of the area: an Adventurer is walking around blind corners on a regular basis, but a fortress can easily set up a corridor where enemies must face a long, unobstructed march through withering fire. Ideally, this corridor should occur right after a blind corner the invading force must follow.
 Maces, Hammers, Flails, Mauls, and Morningstars
Considering that you're going to be hitting limbs most of the time, blunt weapons do the most damage and are most likely to break or mangle a limb, reducing the creature's ability to carve you a second mouth. Blunt weapons don't hurt internal organs much, and are unlikely to remove limbs, so they're less ideal for getting a quick kill on large or heavily-armored enemies, but their high damage makes them perfect for killing weak or small enemies. Blunt weapons are also unmatched when it comes to sending enemies flying.
The maul, despite being a heavy two handed blunt weapon for humans, is the highest damaging weapon in the game.
Dwarves cannot build flails, morningstars, or mauls. The maul is a human weapon, and dwarves cannot wield it, as it is two-handed even for a human. Morningstars and flails can be wielded by dwarves. (Mauls can, however, be used in traps).
 Swords and Axes
Slashing damage causes more bleeding (presumably), but slashing weapons tend to deal less damage than blunt weapons. Slashing weapons are also more likely to cut off limbs, though the exact mechanics are unclear. Removing a limb means you can't hit it again, so if you are cutting off limbs, the odds of hitting the torso or head increase. Axes generally do slightly more damage, while swords have a slight critical boost, causing more internal damage on the head and torso. Thus, swords are slightly geared more towards fighting large creatures, while axes are slightly better for small creatures. Axes weigh more than swords, but it is unclear if this has any effect on the combat mechanics.
 Spears and Pikes
Piercing damage appears to remove limbs only rarely; it is better for torso and head hits. Since torso and head hits are uncommon, due to the number of limbs that can be hit instead, a spear is somewhat of a luck-based weapon. Piercing weapons get stuck on a fairly regular basis, (again, usually in a limb where it can't do as much), but when it hits a torso or head, the victim usually takes organ damage. In this light, a spear is best when fighting large creatures, who are best killed via organectomies rather than cumulative damage.
Dwarves cannot wield a pike; it is a two-handed weapon, even for a human.
Whips do "gore" type damage, which inflicts more bleeding and pain. Also, gore attacks have a higher chance of dealing damage to sub-bodyparts like fingers or eyes. This gives whips a strong tendency to break a victim's joints or poke out his throat or other vitals, thus rendering him unconscious quickly and eventually making him bleed to death, which makes them good against unarmored, living creatures. The downside of using whips is the low overall damage and chance to sever body parts, which makes them almost pointless against armored or undead enemies.
 Burn, Heat, and Cold Attacks
BURN, HEAT, and COLD are possible damage tokens. There are no weapons that do these kind of attacks, but can be modded in. There are creatures that can do burning attacks. It's unknown whether any creatures have heat or cold attacks.
Burn attacks aren't really directly related to temperature or fire, and creatures with fire-immunity can get harmed by them. This kind of attack inflicts great pain.
Heat has attack messages almost similar to burn. This attack is more related to temperature than burn attacks. When a creature is struck down by heat attacks, its body ignites. It's unknown whether fire-immune creatures are affected by this attack.
Cold attacks are pretty much like burn attacks, but with different attack messages. This attack does freezing damage, but nothing else special. It's unknown whether cold-immune creatures are affected by this attack.
 Special Attacks
Some creatures, particularly giant cave spiders, shoot webbing. Webs will be left behind in the tiles the webbing passes over. If you are in a tile with webbing, you are completely immobilized until you can break free of the web. Currently, in the time you take to escape the web you can be attacked a few times, and possibly webbed again. This makes giant cave spiders the most dangerous critters in adventure mode at this time.
Some creatures have special attacks that can inject poison into other creatures. There are two types of poison, one that stuns, and one that paralyzes (which is most common).
When a creature is inflicted by a paralyzing poison in adventure mode, there will be a message where it says that it "feels numb". As time passes, the creature slows down. Eventually it'll become completely paralyzed, unable to move for a long time (depending on toughness). If there are enemies still around, this is most likely the end of the creature. After a while, if the paralyzed creature is still alive, it would recover from paralysis.
There are no ways to cure poison. Also, it can be modded so that player characters can use poison attacks.
Lastly, creatures who are immune to paralysis are immune to that kind of poison.
 Blood Sucking
There are VERY few creatures that have the ability to suck blood. Encountering them is rare. These creatures have special biting attacks that latches and can suck blood.
When blood is drained from a creature, it causes heavy bleeding (depending on the attacking creature's ability to suck blood). Blood suckers may feed or regain health while doing this. Verify
Modding this ability to a playable creature of your choice won't do anything. Only NPCs can use this special attack. (note, this player modded leechmen to be playable and they would sometimes drain blood on attack)
 Fire Breath
Some creatures have the ability to attack by breathing fire at their enemies. Fire breath does damage to creatures that are in the fire and may ignite any equipment they're wearing. Fire breathers normally have immunities to fire.
Dragons breathe dragon fire, which is more powerful than regular fire breath. Creatures with normal fire immunities can be affected by it.
During adventure mode, should you meet a fire breathing creature (Fire imp, Dragon etc.) you can block the fire breath [provided you have a shield [What materials?] and a high enough shield level - tested on expert shield user] If you block the fire breath once, it is likely you are "immune" to the fire as you will constantly block the breath. [Does this work in Fortress mode?]
Modded player characters cannot breathe fire. Only NPCs can use this ability.