Combat System

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Submitted mechanic.png This article covers a submitted game mechanic.

Submitted game mechanics have been fleshed out in detail and are ready for review by the other developers. Once submitted mechanics have been reviewed and agreed upon, they become accepted game mechanics.

This proposal is now considered drafted; many details need to be filled in, but it's ready to be discussed.


Turn Sequencing

1 turn = 1 second.

To clarify - 1 turn is what one character can do with a simple (or in some cases, dual) action. The actions listed below are meant to be "1 second actions". Longer turns are possible, but I think we then must allow for characters having multiple actions (decisions) in a turn - which makes the sequencing a little more complex. In addition, I think this is difficult to balance, because the difference between 1 action/turn and 2/actions per turn is tremendous in combat.

The following is a list of ALTERNATIVE methods for determining sequencing. The core of them (characters take actions outside "real" time) is the same for what follows, with some minor adjustments. Some of the terminology is a little muddled, because the basic stats have yet to be defined. But for now, consider "Speed" to be a stat that determines how fast a character acts in a turn. In some cases this directly maps to a "Action phase" indicating the FIRST possible segment (subsection of a turn) in which a character may act. In both cases, a higher rating is faster.

Phased (constant)

In this method for turn sequencing the turn is divided up in to 10 segments, representing 1/10th of a second. Characters act ONCE per turn, on a given phase (1-10) with faster characters acting first. The characters "action phase" is determined by his (generally speaking) speed and/or initiative stats (to be defined). This makes vehicle and other "constant velocity" movement very straight forward. Something moving 10m/s moves 1 square (meter) per segment. Faster or slower speeds are spread out evenly over the 10 segments (example, something moving 2m/sec would move on phase 5 and phase 1 (note that moving on 10 and 5 would be equivalent - a chart must be specified for all integer movement speeds). Faster speeds will move up to 3 squares in a segment (it is recommended that we simply not allow speeds higher than 30 m/s = 108km/hr = 65mph. 10 segments might result in many "ties" for character actions; expansion to 20 phases (or some other number) is straight forward. Phase 10 is "first" - all characters with a "Speed" (action phase) of 10 act (or reserve their actions), all "things" moving on that phase move 1 square. Things being "driven" can only be steered during their drivers action, otherwise they move in a straight line.

Phased (variable)

This is pretty much identical to the constant version, except that we don't use a fixed number of phases. Instead, the "highest" initiative (action phase) is used as the top of the chart, and phases are counted down from there. This has the advantage of better sequencing for characters (fewer ties if there are >10 possible "speeds"). It makes velocity calculation a little trickery, in that the phasing might change from combat to combat, or even from turn to turn, but computers are good at integer math, and the tactical details should probably be hidden from the player anyway to prevent gaming the system.

Action Points

Chars have AP pool of N points, each action uses M points, players act until they are out of APs. Sequencing (who gets to use their action points first) still must be determined by the speed stat. Things moving at a constant velocity must be handled seperatly, or else vehicles are given erzatz "speed" and "action points" which can only be spend on moving (independent of driver?). This system has the advantage of allowing different actions to cost "wildy" different amounts of points - or slightly different to represent equipment differences (eg., a pump action shotgun might take 5 APs to fire, while a break-action 10+). However, balancing issue come in, unless people are happy with the idea of some characters being able to do 2-3 times as many things in a turn. Using action points generally allows for longer turns in which more things are done, which effects playability (positively or negatively, I suppose is in the eye of the beholder). The phased systems above can be considered a simplification of the AP system where all actions take 1 or 2 actions points and all players have 2 action points. Movement in an AP system typically involves spending 1 AP to move 1 square, anytime during the turn, while the phased systems have more a trade off between "moving" or "fighting" during a given turn.

Plotted Actions (Real-time auto pause?)

This is a quite modified turn-based system where all actors (charcters) "plot" their action for the next turn. All orders are collected by the CPU who then resolves them like a (short) movie scene. Advantages are a very natural combination of "character speed" and "action speed" (i.e, a fast character doing a slow action might end up going after a slow character doing a fast action). There is some question as to FIFE's ability to handle this, but I think Unknown Horizons is a RTS so, it should be no problem. One can also use a "Tactics" skill to give advantage (higher tactics, fewer actions have to planned out in advance). Personally, I have played a few tabletop games like this, and they are always sort of amusing in their randomness.

Type of actions

An action is a player's (or AI's) decision to do *something* during "detailed action" aka "Combat" time. Generally speaking, it is what a single person do in a single second of real time (certain "fast" actions can be combined and 2 can be done per turn/second).


(Needs review)

Move actions

Click on desired destination: [ purpose]

  • Charge / Bug Out [ change range quickly, no attacks except "bash" at end, terrible defense]
  • Dodge [ avoid missile fire, increased defense]
  • Covering fire (hipshots) [cause distractions, lucky hit - no defense mod]
  • At the walk [move delibrately - no modifiers]
  • Double time [between walk and charge, reduced defense]
  • Take cover [maximize missile defense within 1hex]

See acceleration rules below

Command actions

  • Shout a command ([list of actions - tactics lvl 0 - reduced list of commands, lvl 1 full list, lvl 2 "name: command", lvl 3: code words, silent commands]
  • Assess changes (tactics lvl 1?)
  • Surrender [give up]
  • Ultimatum / Bluff [demand foes give up]

Missile actions

Restricted by "distractions" - enemies + 1/2 x friends + terrain:

  • Set stance [prereq. for aim, removes "hip shot"]
  • Aim [increase chance to hit, prereq. for called shot, subsequent "aims" stack to 3-4 levels?]
  • Fire [hip shot unless set] - can move 1 hex if no aim - up three shots from autoloading gun
  • Called shot [shoot at hit location]
  • Spray [fire as many "shots" as possible * may be 1]
  • Reload [different weapons have N reload actions, depending on acessibilty, stuff] [auto take cover if available]
  • Traverse [autofire only: "controlled" spray]

Melee actions

Must be in weapon range + 1 hex to close to enemy, reduces offense and defense:

  • Attack 1, 2, 3... [basic attack keeping offhand for defense - numbers represent different types of attack by weapon type (cut/hack/thrust/club/punch/kick)]
  • Aimed attack 1,2,3 [prereq: advanced level with weapon, reduced attack/defense - higher skill = finer targeting]
  • Feint [prereq: Advanced level with weapon increased defense, increase offense for next attack - special: can retreat 1 hex back]
    • Feint/attack [prereq: 2 weapons, advanced level: attack with increased chance to hit, reduced defense as extra attack]
  • Grapple [ prereq: empty handed - grab opponents arms/weapons. Note this will have to trigger separate subsystem]
    • Extra attack [ 1 or 2 weapons, but restricted for some weapons, decrease defense (slightly less decreased with 2 weapons)]
    • Coup d' grace [ powerful attack - zero defense]
  • All out defense [ no attack, enhanced defense - special: can retreat 1 hex back]
  • Fancy martial arts moves? Throws, trips, disarms, submission holds?
  • = "double" actions, no move allowed.
  • Charge ('slam' attack combined with run)

Reserving, Aborting, and Interrupting opponents actions

With the exception of the "simulturn" option, any sort of phased turn sequence will have a discontinuity where the faster character wishes to wait for a slower character to act first. Since he is faster, it is only fair to allow him to delay or reserve his action until the "proper" time. However, this mechanism is quite powerful, and must be restricted to prevent abuse.

The basic rule is as follows: The Active character can "reserve" his action until something "else" happens. He can then interrupt the normal turn sequence and take his turn "out of order". This requires particular types of "trigger" actions such as:

  • New target appears (moves, or unhides)
  • Enemy attempts to Engage (in HTH combat)
  • Enemy attempts a ranged attack (note that the enemies ranged attack will go off FIRST, this is to limit the power of waiting)
  • Others?

If no trigger occurs during the turn, the character may act after all others (resolve ties from really slow people or other "overwatchers" as normal).

Possible options (could have balance issues)

  • If you reserve at the end of the turn, can you move to the top of the list for next turn? Is there any advantage to this?
  • Can you 'abort' to any action, or only certain ones?
    • Dodge
    • "Hit the Dirt" (take cover)
    • Fire missile
    • HTH attack against one who just engaged you (trigger)
    • Issue verbal command

Movement & Distance

Characters (and animals) have a maximum sprint velocity (m/s) == Vmax => about 10-20 spaces/turn (set by stats). Sustained running velocity is typically half of this value. You can run at 1/2Vmax for some number K1 x END (Endurance) turns. You can sprint at Vmax for some number K2 x END / 10 turns. After this amount of time the character must rest for 100-END turns (or something). At 1/2 this time character will begin to suffer fatigue effects.

Acceleration and Deceleration

Acceleration (and Deceleration) is done by levels. One such accel/decel level change can be taken for free, and a second can be taken if the only actions taken in the turn are "Movement" (this includes charging).

If you are not moving, your velocity is 0. From a standing stop a person can move 3 squares (m) in a single turn, and will now have a velocity of 3 m/s, and still have an action (attack, for example). This number may be different for different creatures; it could be determined by an acceleration stat. 3 m/s or less is considered a walk for humans. For jsut moving, a person can go from standing to 6m/s in 1 turn, then be sprinting (up to Vmax) on the *next* turn (if all he is doing is moving). Note that "dodge-running" has a maximum speed of Vmax/2. Deceleration is similar. If a character is running at 10m/s, and wishes to stop - he must take an entire action to drop to "walking" speed. On the next turn, he can fully stop (and also attack).

Speed, m/s (description) How long? Penalty (to attacks given and recieved, but see angular velocity)
0 (Standing) inf 0
1-3 (Walking) 8-10hr -velocity (V) - only hip shots at V>1m/s!
4-6 (Jogging) ca 4hr -2xV
7-(Vmax/2) (Running) K1xEND -3xV
Vmax/2-Vmax (Sprinting) K2 X END/10 -3xV (No attacks at all)

You may move, without changing facing (see "Turning", below) into any FRONTAL square. If walking, this can be a FLANK or BACK square as well.


Simply put - each character may make a single 90 degree rotation per action (1/turn). A second 90 degree rotation requires a full move action, and character must be moving at a walk or standing still. At the time of any action, or reaction (example to a enemy melee engagement attempt), a character may make a "free" 45 degree rotation (this could possibly be automated by the CPU if the rotation is always advantageous).

Facing (and relation to melee combat)

A character has 8 possible facing in a square (4 sides, 4 vertices). By convention, all rules should treat side and vertex facings as IDENTICAL for combat (this will probably require some numbers fudging). Picture of factings, frontal/side/back squares for range 1 weapons and longer ones

Each facing has 3 Front, 3 Back, and 2 Flank (1 each left and right) squares. You cannot generally attack into Back hexes, and are considerably more vulnerable to attacks coming from these squares. Attacks to and from the side are penalized (or rewarded) only slightly

Hit Locations

In combat (or other sitations) a part of the body will need to be specified. For example, if you use an "aimed" attack at someone you might need to select a hit location or hit location group. Note that "chest" and "abdomen" cover locations that are both vital and non-vital, and some additional wound penetration roll needs to distinguish attacks that hit these locations.

(some artist needs to draw this)

  • Head - Locations 1-2 (1 is "braincase", 2 is "face")
  • Neck - Location 3
  • Shoulders - Location 4/5 (2)
  • Chest - Location 6-9 (4)
  • Abdomen - Location 10-13 (4)
  • Right Arm - 14,16,18,20 (4)
  • Left Arm - 15,17,19,21 (4)
  • Groin - 22
  • Hips - 23/24 (2)
  • Left Leg - 25,27,29,31,33 (5)
  • Right Leg - 26,28,30,32,34 (5)

Melee Combat

Melee combat occurs when an attack with a weapon or open hand is initiated by a character against an "potentially aware" opponent (as opposed to an inanimate object or unconscious foe). The initiator becomes the Attacker and the attacked becomes the Defender. The basis of combat is a contest of skills, using the "most effective" skill (i.e., not chosen by player or AI) for the give characters' current equipping. For example, a character holding a machete will attack with his most appropriate skill in the the tree - Machete / Single handed Edged / Melee combat (moving from specific to general). All melee skills are rooted at the Melee Combat skill, so with an unfamiliar weapon this is the skill that is used. Melee combat skills are assumed to include both "attacking" and "defending" components of fighting, although if a character is using a weapon in each hand, he might be using different skills (or more likely "mixed" skills) for attacking and defending.


  1. Attacker selects weapon, target, subtype of attack where possible (i.e., slash, thrust, bash). Best skill is automatically applied.
  2. IF DEFENDER IS UNAWARE (i.e, surprised, asleep, totally distracted) CHECK FOR SUCCESS LEVEL AND GO TO 5. It is assumed you cannot miss without a 'fumble'. Other states of 'partial awareness' are treated as regular combat with modifiers (in favor of the most aware party!)
  3. (Aware) Defender is assumed to be defending with whatever he has at hand, using appropriate skills (at worse, "Melee Combat")
  4. A contest of skills is resolved to determine if a "hit" has occurred. Note that a 'hit' is not any contact of weapon on body - but rather an effective, well angled blow that has some chance of hurting the defender, even if it still may fail to penetrate his armor. The result of this contest is a "success" level which will determine the effectiveness of the attack.
  5. Hit location is determined - a function of relative facings, elevations, a random factor, and the ability of the Attacker to aim his blow (which is in turn a function of his skill and "effort" in aiming)
  6. Check armor penetration - a function of the armor, weapon, attack subtype, and success level of attack.
  7. Apply subdual damage (cumulative) - weapon multiplier X strength roll (see Zenbitz:Thouhts on health and wounding)
  8. check for wound (function of weapon, success level)
  9. Apply wound effects (death, unconsciousness, reduced effectiveness, etc.)

NOTE: Detailed mechanics and probabilities are left until the skill system is further refined. Similarly actual concrete modifiers cannot be provided until the skill details are worked out; the modification table values are meant to be relative to each other, and are, of course, not finalized.

Weapon Ranges

An average melee weapon (say a machete or fire axe) has a Range of 1.x That implies that it can strike into the surrounding "ring" (except behind wielder) of squares only. The "fractional" ranges can be used to represent "range mismatch" between two Range 1.x weapons (i.e, a Dagger vs. Broadsword), giving an advantage to the longer weapon. This matchup changes for longer weapons (range 2.x) used at range 1. Only weapons with a Range of 2.x can attack 2 squares away. There are some special Range codes specified below.

Weapon RangeAttack @1 Attack@2 Example
1.0 Y N Fist, Dagger
1.x Y N Hand Axe, sword
2.x N Y Spear
2/1 Y Y 2-handed Greatsword

Note to designers: This can be easily extended to 3m weapons, should we require a very long spear...

Engaged status

If Character A strikes (i.e., takes a HTH attack action) at Character B, A & B are said to be Engaged. Engaged status restricts the actions of all engaged parties, generally to resolving the threat in front ("engaged with") them. If engaged, a character may NOT use any missile weapons other than pistols, or take any actions other than those related to attacking or defending in HTH combat. Single spaces moves and rotations in place are allowed. The exception to this is that he may attempt to Disengage, which is a special move action requiring some "melee combat skill roll" between the disengager and his enemies. In general, attacking someone in HTH results in both parties being engaged, however, there are exceptions made for "charging" or "passing" attacks in which the parties do not end up adjacent to each other. You may strike anyone in range, whether or not they are already engaged in melee combat with you (however, there are cumulative attack penalties for "ignoring" people you are engaged with), this can result in adding new parties to the engagement.


Note: Note sure this is really worth the code weight. Grappling is a special Engaged status that results when one party sucessfully uses an unarmed combat skill on his opponent. It represents a state where the two parties are locked in a wresting match. The only weapons that can be used are very small, reach of 1.0 or less (including pistols - single handed guns). Any 3rd party attacking someone who is "Grappling" has a 50% chance of striking either party! Unlike regular "engaged" status, you can only attack the person you are grappling with. No 3rd person can "join in" the wrestling match (this is just a simplification). Both parties are considered to be prone (?) while grapp

Modifiers to Melee Combat

Situation Effect Examples
Dedicated blocking implement + DEF has a shield
Defender Distracted - DEF Being shot at, engaged with >1 foe
Attacker Distracted + DEF As above, plus confined area
Successful feint -DEF "Feint" is a double action with an extra skill contest - used when both parties have high skill levels
Wounded/Stunned/Exhausted +/-DEF Effects the suffering party
Prone +/- DEF Prone person is worse off in melee combat
Bad lighting -ATT/-DEF Reduces effective skill levels of both
Positioning -DEF Bonus for attacking SIDE or REAR (larger for rear)
Soft Cover +DEF If either party is in cover, both get a defensive bonus
Hard Cover +DEF If either party is in cover, both get a def bonus - hard cover also totally blocks locations
>50% Hard Cover NO ATTACKS You cannot attack from >50% hard cover
Longer HTH weapon +ATT See decimal weapon ranges
Using weapon at Short range -ATT for example, a range 2 weapon at range 1.

Missile (Ranged) Combat

Ranged combat is initiated in a manner similar to Melee combat, except that the defenders skill is not relevant. Barring special engaged cases, the attacker can select any target he can see "has a Line-of-Sight" (LOS) to (but see "Indirect fire"), and fire. Note that various "pre firing actions" (bracing, aiming) can effect the accuracy of the attack ("shot"). In general, a shot's accuracy will decrease with increasing range. The "flowchart" is essentially the same as in melee combat, with the exception that the 'success level' is purely a function of the the attackers (modified) skill.

Targeting an area

Some weapons, particularly thrown weapons like hand grenades - do not need to strike their opponent to be effective. All that is important is delivering the weapon to a particularly location (square). In general it is easier to hit a location (1m x 1m is a large target) than an active, defending person. Some weapons will need to be tracked even if they "miss" their target; typically they might bounce a single square in a random direction.


The interaction of Melee and Ranged combat is a complex one. In general, a "ready" missile weapon can trigger in a fraction of the time a single or combination attack from a melee weapon (including open hands) can occur. To this end, if a (putative) defender holds a weapon and is ready to fire, and an opponent takes an action that will engage the defender, the defender may abort his next action and fire first out of sequence - but only to attack his attacker. There is a penalty to this attack, if the 'defender' (soon to be attacker!) has not previously reserved his action.


Taking cover is an important part of missile combat in which the fire exchanged is likely deadly. It is expected that characters engaged in a fire fight will take what cover (hard or soft) as they can, falling prone if necessary, and generally will sacrifice movement and offensive options to stay alive.

Indirect Fire

As an exception to the LOS rules, some weapons can be fired at a "known location" (see #Targeting an area above). This can be an effective way to hit someone hiding. The interface may show a person with a "known location" and yet out of LOS as "greyed out" or shaded. Most guns are not capable of indirect fire. Weapons capable of indirect fire may have a MINIMUM range as well as a maximum (for example, a long bow can shoot indirectly, but only at long ranges).

Direct Fire

This is the standard mode of attacking someone with a missile weapon. A LOS is required. There are three "subtypes" of direct fire in order of increasing chance of scoring a hit, listed below.

Hip Fire

Hip fire represents an uncontrolled, unaimed shot "in the general direction" of the target. It is typically used while the firing is moving, highly distracted, or otherwise desperate. There is a very low, nearly random chance of hitting the target, although some types of weapons (shotguns) may have a reasonable chance of hitting something. The users skill level will only influence the chance of a successful hit to a small degree, and familiarity with the specific weapon is more useful than training or physical prowess.

Sighted Fire

This is a missile attack that represents the fireing taking a basic stance - i.e, spending at least part of a previous action to draw a bead on a target. No more than a single square can be moved while making a 'sighted' attack (and an attack penalty is also given for moving at all). Sighted fire is required to give the full measure of a missile weapon skill, however, the shot fired is a "quick" one and as such cannot be directed at a particular target - but can be directed at a "quadrant"

Aimed Fire

This is a missile attack for which the firer has spend >1 action "drawing a bead" on his opponent. The firer receives increasing bonuses to hit his target, and can direct the shot to increasingly fine target locations. Generally, to hit a target at long or extreme range will require a few rounds of aiming to have a reasonable (ca. 50%) chance of success. One possible implementation would be that after 1 action of aiming "Aim-1", the character could select a "quadrant" to hit (left/right/up/down), and after 2 actions "Aim-2", he could aim at a body part (Head, Left Arm, Right Arm, Left Leg, Right Leg, Chest, Abdomen) - each encompassing ca. 3-5 hit locations. At Aim-3 (3 sucessive actions) he could aim at an individual hit location (one out of 35). Additional penalties for targeting could be imposed as well (at Aim-3 maybe there is no modifier to hit a "quadrant" but still a penalty to hit the left elbow). Within a "grouped" target location, the determination would be essentially random.

Modifers to Missile Combat

Situation Effect Examples
Defender Distracted - DEF Being shot at, engaged with >1 foe
Attacker Distracted + DEF As above, plus confined area
Successful feint -DEF "Feint" is a double action with an extra skill contest - used when both parties have high skill levels
Wounded/Stunned/Exhausted +/-DEF Effects the suffering party
Bad lighting -ATT/-DEF Reduces effective skill levels of both
Soft Cover +DEF If either party is in cover, both get a defensive bonus
Hard Cover +DEF If either party is in cover, both get a def bonus - hard cover also totally blocks locations
Moderate Range +DEF per weapon specs
Long Range ++DEF per weapon specs
Extreme Range +++DEF per weapon specs
Attacker or Target moving -velocity (to attack) This penalty actually decays with range, and is only velocity tangential to the direction of fire
Target dodging +DEF only at < Extreme range
Attacker Braced or "set" +ATT required for aimed fire
Multiple shots/action +DEF per recoil value of weapon
Shots on same target; sucessive actions +ATT see also aim
New Target +DEF per weapon specs
Scope on weapon +ATT Reduces range effects

Effect of leadership and tactics skills

Possible concepts

  • Stack actions - the better your leadership, the fewer actions you have to sequence.
  • Number of verbals commands allowed to use
  • Improved chance of "AI" friends following orders correctly
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