6 - Combat

A typical combat turn is roughly 3 seconds. The basic order of operations for a combat turn:

1. Each combatant sets the offensive and defensive tactics

2. Each combatant declares their actions for that round

3. Everyone rolls initiative (3d6+Tactics)

4. Starting with the highest initiative, resolve each set of actions

At the start of each combat turn, each side sets their offensive/defensive tactics (oT/dT) by assigning points from Tactics. The GM should advise the players whether NPCs are fighting normally, aggressively, or defensively (splitting tactics, more to oT, or more to dT) and give the players a chance to respond. Each participant is free to adjust until everyone settles on their final tactics for the round. This is meant to allow opponents to adjust to one another (wait, he's putting everything into offense? Crap, I want to fight more defensively in case he goes first). The GM records  oT/dT for each combatant for the round: oT will serve as a bonus to all attacks, while dT adds to the defensive skills.
After tactics are set, each combatant declares their actions for the round. As with tactics, each combatant may change their actions in response to the stated actions of other participants, until everyone settles on their stated actions. The GM records the stated actions of each combatant: this serves as a blueprint for what everyone will be doing for the combat turn (roughly 3 seconds of combat).
Note: an exception to the first two steps is if any of the combatants are hidden from others. Such combatants would declare tactics and actions as normal, but in secret from those who are unaware of them at the start of the combat round.
Next, everyone rolls 3d6+Tactics to determine their initiative order, set highest to lowest. If initiative is a tie, then it's the GM's call who goes first (typically based on who has the highest tactics, FIN, etc.). Players can decide for themselves who goes first if they tie each other. The GM records the order of combat.
Starting with the highest initiative, each participant performs the actions they declared at the beginning of the round. If performing multiple check actions (any action that requires a check), every check action suffers a negative penalty for the number of actions committed to in that turn. For example, If someone wishes to walk toward some foes and make three attacks,  each attack suffers a -3 penalty (because they're attempting three check actions). If someone changes their action to anything else at this stage, they suffer a cumulative -1 to every action they changed for all of their checks, even if they opt not to do some of their earlier stated actions. This allows players to adjust to the changing dynamic of the battlefield while penalizing them for hesitating and changing their minds in the middle of combat. If that person wanted to run and make three attacks, that would be -4 on every check (as run required a check on the Run skill).
Once everyone has completed their turn, the next round begins and the process starts over.
Movement: This stat gives a value for how many meters a creature can move (walk) within one combat turn. Most normal-sized characters will have a move of 4 meters. Jogging doubles a base move (x2), running triples it (x3), while sprinting quadruples it (x4). Jogging, running, and sprinting are handled with a Run skill check, adding successes (or subtracting failures) from the total by one meter per success (or minus one per failure),  as detailed in the Skills section. During a combat turn, it is reasonable for a character to move and fight, but movement with ranged weapons imposes a penalty (base -1 for walking), with a larger penalty for using the Run skill the same turn: running imparts a negative penalty equal to the movement multiplier (this penalty also applies to any other combatant attacking the character with a ranged weapon).
For example, if a character is sprinting (x4 movement) and using a ranged weapon in the same turn, they suffer a -4 penalty to their ranged attacks. For melee combat, movement imposes no penalty, but running does (minus 1/2 multiplier, rounded down as always), however they do get a wound damage bonus (+1 per multiplier, i.e. x3 movement grants +3 damage) if they travel at least 4 meters in a straight line towards their target before making the melee attack (essentially a charge, where you use the momentum to boost your damage).
Movement is a part of the combat turn, and happens simultaneously, rather than the traditional way of many role playing games where movement happens on each individual's turn. This means that if any combatant closes range to engage in melee combat during the turn, adjust ranges accordingly. EXAMPLE HOW THIS WORKS

Overview of Attacks

An attacker must determine if they are trying to kill or incapacitate their opponent – this will either increase damage to wounds or stress by adding successes to the base damage value listed (if no value, assume base is zero). Weapons always inflict base damage, so a weapon with a base W damage that is being used to incapacitate (adding success to S damage) would do base W damage plus S damage (as base S damage is zero in this example, S damage would equal successes on attack roll).
The target number to hit is either 10 or the Defense target number if the target is attempting to defend itself.  The attacker uses their appropriate offense skill for the check, modified by their offensive Tactics (oT), any additional bonuses and/or penalties. After the attack is rolled, if there are zero or more successes remaining for the attack, the attack is a hit. Successes modify the damage of the weapon: add the successes to W damage for lethal attacks and subtract from the target's W. For stunning attacks, add successes and S damage of the weapon together and subtract from the target's S. In either case, Armor of the target may reduce the damage taken. 

So an Attack Check is:

attacker skill bonus (stat + skill + gear) + offensive Tactics + modifiers versus target's defense (defense target or 10 if not defending) + target's defensive Tactics
or, put more simply
Skill bonus + oT versus Defense + dT

Defense

Armor

Armor is typically gear worn by characters, though some creatures may have a natural armor. Worn armor comes in three sizes: light, medium, and heavy. Aside from penalties and restrictions imposed on those who wear it, armor also has a value that reduces the damage done to the wearer. Against weapons with a larger die code category (typically equal to the smallest size of the weapon, if it lists more than one), armor reduces damage equal to the armor value. Against weapons of larger size, the armor value instead converts its value in wound damage to stress damage. 

Dodge, Parry, or Block

There are three skills used in defense: dodge, parry, or block. Defense skills are calculated differently than other skills - rather than applying a bonus to a skill check, defense skills (and their linked stats, plus gear modifiers) are added to a base target number of 10, giving the target number needed to hit. All defense skills are considered common skills (meaning they can be used at no penalty untrained).

Dodge: moving to avoid hits, this defensive skill does not normally get bonuses from equipment. This is the simplest form of defense. 

Attack vs. Dodge
Attack Check + oT vs. target's Dodge Skill + dT

Parry: an attempt to deflect an incoming attack; if the defender goes after the attacker they can attempt a counterattack (see below). Unarmed counts as -3S, so a normal-sized creature trying to parry unarmed would be considered to be using a 1S (tiny) defensive weapon. Weapon size differences favor the attacker, though some defensive weapons count as smaller sizes in addition to their normal one. If an unarmed parry fails, defender takes 1/4W damage as S damage.

Attack vs. Parry
Attack Check + 1 (per weapon size difference) + oT vs. target's Parry Skill +dT
Failures = bonus to counterattack

  A counterattack is possible when the defender successfully parries an attack before their go in a combat turn (if their attacker rolled higher initiative or defender allowed attacker to go before them). After the successful parry (attacker rolled a failure), those failures become a bonus to attack for the defender IF they go after the attacker and IF they attack the same person they parried (first attack only). 

Block: an attempt to absorb the attack with a weapon (shields are considered defensive weapons). If the attack hits with a success of five or less, add the defensive quality of the blocking item to your armor value. As with parry, when blocking a weapon of a different size, the attacker gains a +1 to attack per size difference of weapons, though some defensive weapons count as smaller sizes in addition to their normal one. Unarmed counts as -3S, so a normal-sized creature trying to block unarmed would be considered to be using a 1S (tiny) defensive weapon. If an unarmed block fails, defender takes 1/2W damage as S damage.

Attack vs. Block
Attack Check + 1 (per size difference) + oT vs. target's Block Skill +dT
Success of five or less = defender adds defense quality to armor

When weapons of different tiers smash against one another with blocks, the weaker weapon may be Sundered. An attacker may choose to put all damage into the blocking weapon in an attempt to sunder it, gaining a bonus to the Sunder check target number equal to the successes rolled on the attack. 

Unarmed block/parry: parrying or blocking a weapon attack while unarmed doesn't typically involve deflecting the weapon itself, as this is effectively a hit on the target. Instead, allow parry/block for melee weapons on the assumption the arm of the attacker itself is deflected/blocked (or a part of the weapon that is safe to engage). For example, with a knife attack against an unarmed foe, that foe is attempting to deflect/block the arm holding the knife. Note an unarmed defense counts as -3S weapon size for the defender.

Full Defense: forgoing all actions for that turn, a defender could choose full defense. Until their next turn, all attack checks against  the defender are Inferior +1. Full Defense cannot be taken if the defender has had any actions that turn aside from movement.

Parry/Block ranged attacks: Ranged attacks may be parried/blocked by any opponent within Nearby range (within 2m) of the attacker as if it were a melee attack. When a ranged attack is made against any target while within reach of enemy allies (assuming they are free to interfere), add the parry or block skill bonus of each foe to the defense of the target. When parrying ranged weapons within reach, such a defense is considered to knock the aim harmlessly away rather than absorbing it with your weapon/shield/arm. For a defender attempting to parry an incoming projectile, the ranged attacker gains either a bonus or Superior checks, depending on how unlikely such a defense seems to the GM. For example, trying to parry a bullet with a sword may seem folly (GM decides to grant Superior +1 to attack), parrying an arrow with a sword unlikely (GM grants +3 to attack), while blocking an arrow with a shield seems reasonable (no modifiers).

Incapacitated Foes: a stunned or dying foe is particularly vulnerable. Against melee attacks and ranged attacks at point blank range (Nearby), the attack is considered Superior +1, or in particularly dire circumstances (for the target), Superior +2 or more (for example, if the target is unconscious). If an ally is Nearby to the target, they may try to block or parry the attack normally - the attack would no longer be considered Superior, though any damage still goes to the incapacitated target. Against ranged attacks beyond Nearby range, defense is target 10, as the target isn't defending itself, and the best an ally can do is shield the body and take the damage themselves (though Block with a shield may still be used normally).

Sunder

When gear is sundered, it suffers a reduction in one of its stats. Crafting may be used to repair the item, so make a note on the item to keep track of its original stats. For example, if a weapon suffers a -2 to its offense quality, reduce that quality and record a note for that weapon: Sunder (-2 offense). An item may only be repaired back to its original stats.
Sunder (weapon): using an inferior-tiered weapon against a superior one (or striking any object tougher than the weapon) may sunder it, damaging the offensive or defensive quality of the weapon. If the inferior weapon was used to attack, it's offensive quality may be affected, while if used to block a superior weapon, its defensive quality may be damaged. Roll 3d6+Quality (whichever is affected) versus a target of 10 + 2 per size difference (note this is a negative penalty if the superior weapon is smaller), plus the difference in tiers between the two weapons. For each two failures, subtract one from that quality. If either quality is reduced to -5, the weapon is broken/useless. If both weapons are the same tier, both roll a sunder check at Superior +1.

IF weapons block of different tiers, the lower tier (both Superior+1 if the same tier):
Sunder Check (3d6+Quality) vs. 10 + (2 x size difference) + tier difference
Sunder Check vs. 10 + (2 x size diff.) + T diff.
For every 2 failures = -1 Quality

Example: say a fine sword (T4) is blocked by a primitive buckler (T1) with a defensive quality of +3, and suppose the buckler is one category smaller than the sword (small versus medium). Each time the sword is blocked by the buckler, a sunder check is needed (as the sword has a higher tier than the buckler).  The target is 10 + 2 (2x size difference, in this case 1 as it's a light shield versus a medium sword) + 3 (the tier difference, in this case T4 - T1 = 3), so the sunder check is 3d6+3 (the defensive quality of the buckler) versus a target of 15 (10 + 3 from tier + 2 smaller defense weapon). If they roll a failure of three, for example, two of those failures drops the defense quality by one, so the defensive quality of the buckler drops to +2 (+3 minus one per failure of two), and sunder checks are now 3d6+2 (the new defensive quality of the buckler).

Sunder (armor): whenever a character suffers an injury from a weapon with a higher tier and/or heavier weapon than their armor, that armor may have to make a Sunder Check. Roll 3d6 + armor value versus a target of 10 + 2 (per size difference, if the armor has a smaller size category) + difference in tiers (note, if hit by a heaver but lower-tiered weapon, the target number will be lowered). For every two failures, reduce the armor value by one. If the value is reduced to zero, the armor is considered broken/useless. So, when struck by a weapon that is a higher tier and/or larger than the armor:

IF higher tier or heavier weapon hits armor:
Sunder Check (3d6 + armor value) vs. 10 + (2 x size difference) + tier difference
Sunder Check vs. 10 + (2 x size diff.) + T diff.
For every 2 failures = -1 armor value

Example: say a character wearing light armor (T3) with an armor value of 3 is hit by a masterwork heavy sword (T5). As heavy is two size categories bigger than light, that's +4 for size difference, and the tier difference grants another +2 (T5-T3). Either factor calls for a sunder check, in this example they're added together, so each time the character wearing light armor is hit by the heavy weapon, the wearer makes a sunder check by rolling 3d6 + 3 (armor value) versus a target of 16 (10 + 4 size difference + 2 tier difference). For every failure of two, the armor value is reduced by one, so a failure of six or more would render the armor useless. 

Example: say another character is wearing heavy armor (T3) with an armor value of 6 is hit by a fine dagger (light weapon, T4). Though the dagger is smaller, it has a higher tier, so a sunder check is needed. The target number gains +1 for tier difference (T4-T3), but a -4 for size difference (light dagger vs. heavy armor), so the sunder check is 3d6+6 (the armor value) versus a target number of 7 (10 + 1 - 4). A blunder would be needed on the sunder check to reduce the armor value (in such an unlikely situation, perhaps the dagger strike got really lucky and severed critical support straps). 

Multiple Attacks

In melee combat, attacker may choose to attack multiple times by suffering a penalty to each attack. Penalty is -1 per attack and if the attacker uses a Run Check to move, apply a negative penalty equal to movement multiplier (so Jogging -2, Running -3, Sprinting -4) but a bonus to damage (if moving in a straight line). GM is the final authority on the number of attacks possible in one turn, considering the size and speed of the weapon - a good rule of thumb: maximum number of attacks equal skill rank plus one (so one at +0, 2 at +1 etc.). Also keep in mind that if the character moves more than his movement allows, he'll also need to make a run check, which imposes additional penalties.

Area Attacks

For attacks that affect an area and could hit multiple opponents, treat it as a ranged attack that may affect anyone within 2 range categories of where the attack originates (let's call this the blast point). If a target is closer to the blast point than its base range, make the check as Superior +1 per closer increment. If beyond the base range, Inferior +1 per increment (max 2).
Example: let's say a grenade [Blast Point Range: Nearby | 2d6W] is used against a group of foes by an attacker with a skill of 15. If they'd managed to affix it to an opponent (less than Nearby range) the check would be Superior 1, targets within 2 meters (Nearby range) would be affected normally, targets within 4 meters (Close range) would be Inferior 1, targets within 10 meters (Short range) would be Inferior 2, and beyond 10 meters we ignore all other targets.

Burst Fire

Semi-automatic and automatic firearms may use multiple rounds in a single attack to increase damage. If firing more than one round, take the number of rounds fired as a penalty to attack, but multiply the success by the number of rounds fired. The penalty may be modified by circumstance (a 9mm SMG does not have the same level of recoil as an M60 machine gun), for example a weapon with a good recoil suppressor might only suffer 1/2 recoil.
For ammo, instead of 15+, lose one count on  a natural roll of 14+ (increasing the chance to  16%).
Example: a 2-round burst would be at -2 to hit but successes would be x2, so a success of 3 would be treated as success of 6, while a success of 2 would be treated as a success of 4 (note, in this case, two successes or less is no better or even worse that squeezing off a single shot, as without the -2 burst penalty the the successes would be 2 higher - hosing an area with bullets rather than aiming and firing once doesn't always get better results).

Maximum burst:
2 pump-action
4 semi-automatic
6 burst-fire weapons (typical up to two 3-round bursts)
8 full-auto weapons

Spray-n-Pray

Alternatively, multiple rounds may be fired in the hopes of a lucky shot. Each shot takes a penalty equal to the number of rounds fired, but each attack is rolled separately. Use maximum burst as the maximum number of attacks in one round. GM may also apply additional penalties if the targets are spaced apart.