Powers and Perils

Mass Combat

NOTE - The following system is adapted from the Mass Combat rules in "Roleplayer" Magazine #30 by Brett Slocum and was originally for the GURPS rules system, ©Steve Jackson Games.

It has been converted to fit the Powers & Perils rules system. Notes on converting the military force notes in the Culture book will also be included. Further, I have slightly modified some of the TS numbers Brett used to better fit the P&P world -- elephants were WAY too big.

This system is not a set of "war game rules" for gaming out a long battle in full detail. Instead, it gives quick answers to the most important questions for a roleplaying campaign: Who won? and What happened to the PCs? Costs are also given for raising and paying military units, for those campaigns in which the PCs are, or want to become, military leaders.


Each military force contains a number of units, each with a single type of fighter. For instance, mounted knights and yeoman long bowmen would be treated as two separate units. Most units should be from 10 to 500 men; the GM has the last word on what may be a unit.

Each unit has a Troop Strength reflecting its size, type, and quality. A force's Troop Strength is the sum of its units' Troop Strengths. All units are recorded on a Force Roster (a blank form is at the end of the article). Each unit has a designated commander, who may be a PC or NPC. The force has a force commander, as well.

In a battle, the opposing commanders roll a Quick Contest of their Strategy skills, modified by Troop Strength and other advantages. The contest determines who wins the battle and how many casualties were taken. Meanwhile, each PC's Battle skill and choice of Risk determine his chance of Survival and Glory.

This procedure lets the GM reduce a long battle to a very few die-rolls. Again, this is not a wargaming system, but a roleplaying aid.

Mass Combat Turn Sequence

The system has seven steps for each battle (or for each day of an extended battle):

  1. Determine each military force's makeup by unit. Determine each unit's Troop Strength. Total the units' TS for the force's TS.
  2. If special abilities (magic, psionics, superpowers, etc.) are being used, determine each military force's Extraordinary Strength. Allocate ES points to the special effects in both offense and defense. Resolve special effects.
  3. Roll for Catastrophe for each force.
  4. Determine each PC's Battle skill and Risk factor, then roll for Survival and Glory.
  5. Modify commanders' Strategy skills by:
    1. Catastrophe, if any.
    2. Relative Troop Strength.
    3. Defensive position.
    4. Special unit superiority.
    5. Glory (or death) of unit leaders.
    6. Special circumstances.
    7. GM's appraisal of the two commanders' battle plans.
    8. Use of magic, assassins and diviners.
  6. Quick Contest of effective Strategy skills
  7. Each PC on the losing side makes a second Survival roll.
  8. Determine casualties for each army (and, if it matters, for each unit).

The Armies

The first step in fighting a battle is determining the composition of the opposing armies. Throughout history and literature, many types of military organization have been developed, some more "organized" than others. In general, there are three main classes of military organization (listed in order from most to least organized): ancient, feudal and tribal.

Ancient Armies

Ancient armies often displayed complex organizations that were not matched until the Napoleonic era. The best-known examples are Greece and Rome.


The Classic Greek armies were organized as follows:

The Spartans had six morai and Athens had ten, one for each tribe of Athenians.


The organization of the legions of the Roman Empire (in the period 100 B.C. to 300 A.D.) was as follows (see GURPS Imperial Rome for more details):

Roman auxiliary cavalry was divided into units called alae, between 500 and 1,000 men strong. Each ala was divided into smaller units called turmae, which had about 20-40 men trained to work in groups of 6-10 men each.

Alae were led by a tribune; the turmaes were commanded by decurions (Rank 3). There were 1-4 decurions on each turma; in theory, they commanded units of 10 men.

Feudal Armies

Feudal armies are much more loosely organized. The main constituents are the feudal levies. These march to battle under their local leader. Once with the field army (which is simply all the troops under a single command for a battle or campaign) they are formed into ad hoc units with similar equipment and the senior man in each such unit is designated its commander. Such units are usually no more than 100 strong; that is about the largest force that one man can control by voice and hand signals. These units are normally called companies and their commander is called a captain. Such appointments are only for the campaign; they do not require the Military Rank advantage.

The captain appoints a petty officer for every ten soldiers; these also do not require Military Rank.

In addition to feudal levies, some feudal armies had small, permanent units, usually the rulers' elite guards. These would be organized along more modern lines.

The higher appointments of a feudal army are also ad hoc. The force is usually broken into three components: Van or Vanguard (the advance guard, which marches first), Main and Rear. Each body is under a commander selected by the king. The commander is usually a senior noble or veteran mercenary; again the appointment is only for the campaign. Each commander selects a number of aides, ranging from messengers to senior advisers.

Mercenary forces in a feudal setting can be of any size and organization. Anyone who can attract a following can set himself up as a sell-sword. They usually ape the composition of the armies around them. Commonly any leader who can supply up to 100 men is called captain, while one who can supply several companies calls himself a general.

Tribal Armies

Primitive societies fight by tribe, clan and band rather than in any organized formation. The only title of command is chief, and may represent anything from half a dozen rogues to thousands of warriors. Some tribal armies include female warriors and, therefore, can field relatively larger forces.

NOTE - In order to make life simple, all Perilous Lands armies should be based on a unit of 100 men.

Troop Strength (TS)

The next step is determining the strength of the soldiers within the army. The Troop Strength value of an individual in a unit depends on his type and quality. Multiply this value by the number of men (or other creatures) in the unit for the unit's total TS.

Troop Type

Each unit is composed of a single troop type. All persons in a unit are similarly equipped. Troop types are differentiated by armor, weapons and mobility.

Usually armor and weapons are lumped together into classifications of "Heavy," "Medium," and "Light." Heavy troops have rigid armor and heavy, or "shock," weapons; medium troops usually wear flexible armor (e.g. chain mail) and have somewhat less damaging weapons; light units have little or no armor (leather or less) and have less damaging weapons. A final division is whether the soldiers have formal training in weapons and other military matters. Soldiers without training (and often with no armor and improvised weapons), such as feudal peasant levies, are called "irregulars." Beware of underestimating the strength of irregulars, since they can still be battle-hardened elite warriors (see Troop Quality and Morale below).

Issues of troop mobility come down to whether or not the soldiers use vehicles for transportation and in combat. Those who walk are called "infantry" and those with some vehicle are usually called "cavalry," be it a horse, a chariot, or a flying beast (air cavalry).

If a unit also uses ranged weapons, a bonus to the Troop Strength is added. Those troops with specialty weapons, such as artillery, and members of non-human races are put into separate units.

Some units treat a group of soldiers as one unit, usually the crew for a large piece of equipment, such as artillery. The TS of these units includes the crew. The crew has no separate TS, except when they get separated, such as in a Rout. In this case, treat these soldiers as TS 2.

The following tables provide guidelines for the Troop Strength of various troop types: (with codes)

[3] Light Armor (AV 0-1): +1
[2] Medium Armor (AV 2-3): +2
[1] Heavy Armor (AV 4-5): +3
[+] Magical Armor: +1/2 added AV (round down)
[C] Light Weapons (None or WSB -1): +1
[B] Medium Weapons (WSB 0 or +1): +2
[A] Heavy Weapons (WSB +2 or more): +3
[$] Fine or Very Fine weapons: +1
[+] Magical weapons: +1/2 added SB (round up)
[#] Light Horses (Riding I, II): +1
[##] Medium Horses (Riding III, IV; War I, II): +2
[###] Heavy Horses (War III, IV): +4
[%%%] Flying mount (Pegasi?): +5
[-] No stirrups: -1
Ranged Weapons
[>] Sling, javelin: +1
[>>] Ordinary bow: +2
[>>>] Longbow, composite bow or crossbow: +3
Special Weapons
[O] Light Chariots*: +5
[OO] Medium Chariots*: +10
[OOO] Heavy Chariots*: +15
[K] Small Ballistae: +15
[S] Small Siege Engines: +25
[SS] Large Siege Engine: +50
[X] Creature/Monster@: +(OCV+DCV)/4 + CDF + NAV - NWI/2 (round down)
Other Modifiers
[~] Irregulars: -1/3 TS (round down)
*Includes crew and horses -- add optional archer of same weight class.
@Minimum value -- additional physical abilities such as breathing flame or the like must be carefully considered. If the creature is intelligent and uses weapons or armor, add the proper equipment modifiers.

The code allows one to compact the information on a unit and is entirely optional. It allows one to quickly determine quality and equipment at a glance.

EXAMPLE - A unit of Marentian Heavy Knights (Heavy Armor, Heavy Weapons, Heavy Horse) would have a base TS of 10 and a code of A1###. If they were also equipped with spears, their base TS each would be 11 and their code A1###>.

NOTE - Because of the desire to keep things simpler, feel free to add archers to groups in even increments, pro-rating the missile weapon modifier. Thus, a 100 man infantry with Med. Weapons and Med. armor (+4) has 1/3 of it's force equipped with longbows (+3, x 1/3 = +1), so the "average" man has TS +5 and the unit has a value of 500.

Changes to mass combat codes: Looking again at the codes, they are not very useful and don't show the unit type like a wargame might. The following may be more useful:


For X:
L = light
M = medium
H = heavy
If weapons and armor differ, use two letters, weapons then armor.
For Y:
F = Footman
P = Pikeman
A = Archer/Crossbowman
S = Spearman/slingman
C = Cavalry
CA = Cavalry Archers
For Z (optional)
-I = Irregular
Quality should be in (parenthesis)
(E) Elite
(V) Veteran
(S) Seasoned
(A) Average
(G) Green
(R) Raw

The Stirrup

There is some controversy over the value of stirrups for cavalry. The traditional view is that stirrups significantly increased the effectiveness of cavalry, while some military historians say this claim is overblown.

For these rules, cavalry troops without stirrups have a -1 TS penalty, as shown in the Cavalry table above. They are limited in the weapon tactics they can use and the missions they can perform. Cavalry charges using couched lances cannot be performed without stirrups. Cavalry without stirrups will generally be used for scouting, raiding, flank and missile attacks, and charging broken or shaky formations of infantry. If battle plans call for cavalry to charge well-formed infantry, especially pikemen, the GM should penalize the Strategy roll appropriately.

Though Light Cavalry have the same Troop Strength as Light Infantry, there is a Special Unit Superiority bonus (see below) for cavalry, so a completely LC force gets a +3 Strategy bonus against a force composed entirely of infantry, the equivalent of a 2 to 1 advantage.

TL Differences

When armies of differing TLs fight, a special adjustment is made to compensate for advances in tactics, logistics, medicine and other fields, plus the sheer shock value of advanced weaponry: the more advanced army's gets a bonus to the Strategy roll equal to the difference in TL+2. So, a TL5 army attacking a TL3 army would add +4 to their Strategy roll. A small, technically advanced force can still be overwhelmed by superior numbers, better strategy, or unlucky accidents like anyone else. GMs who feel this adjustment is too unbalancing can ignore it, reduce it or put an upper limit on the effects to the Strategy contest contributed by TL.

NOTE - In P&P terms, most civilized lands are at TL3, barbarian cultures at TL2 and wild cultures at TL1 or 0.

Increases in TL may also increase the effectiveness of soldiers in large numbers. Therefore, the limit of 10 to 1 on bonuses to the Strategy roll for relative TS is waived for the higher TL army when the difference in TL is greater than 2 (see Relative Troop Strengths below).

Troop Quality and Morale

Troop quality is determined by the average experience of the men in the unit. This directly determines the unit's base Morale (see table below).

If the campaign situation or adventure does not dictate the quality of a body of troops, determine troop quality by rolling three dice on the chart below.

Use the same chart when determining the quality of a newly-raised unit (see Raising Troops) or when recruiting replacements -- in this case, it gives the average quality of the replacements you were able to hire.

Morale is used to determine the reactions of units due to losses and overwhelming odds. More experienced soldiers are more likely to hold their position in a bad situation than raw recruits.

Troop Quality Table (roll 2d10)
DieTroop Quality Battles Fought Base MoraleTroop Strength Base Pay & Roll Cost to Raise
2*Elite (E)15++72 x base TS +50%
3-6* Veteran (V) 10-14 +6 1.5 x base TS +25%
7-10 Seasoned (S) 6-9 +5 1.2 x base TS +10%
11-14 Average (A) 4-5 +4 base TS base
15-17 Green (G) 1-3 +2 .8 x base TS base
18-20 Raw (R)(t) 0 +0 .5 x base TS -20%
*Roll again if you were trying to raise a new unit, or to recruit more than 10 men.
(t) No battlefield experience. If troops of this quality are also Irregulars (no military training), their morale is reduced by an additional -3. In addition, morale rolls fail on a roll of 5 on the dice in addition to 2-4.

Typical Skill Table

Typical Skill Table
Troop Quality CEL Weapon EL
Elite 10 7
Veteran 8 5
Seasoned 6 3
Average 4 2
Green 2 1
Raw 0 0

Unit Commander and Morale

A unit commander's leadership can affect the morale of his soldiers. Add Leadership EL/3 (round down) to the morale of the force. If the unit commander does not have the Leadership skill subtract 2 from the morale of the unit.

The commander with the greatest leadership is considered the leader of the force, limited by levels -- military forces will not be lead by irregulars, irregulars will not be lead by rabble.

When a unit gets a new commander (no matter how experienced), drop all troops except Raw to the next lowest Quality.

Initial: 50
NEL: x10
Max: (W+Em)/10
Initial: 60
NEL: x12
Max: (I+Em)/10
Initial: 50
NEL: x10
Max: (I+Em+W)/15

Force Commander's Experience Table (roll 2d10)
Die Roll Quality Battles Strategy Leadership
2 Elite 15+ EL6+1d6 EL6+1d6
3-6 Veteran 10-14 EL4+1d6 EL4+1d6
7-11 Seasoned 6-9 EL2+1d3 EL2+1d3
12-16 Average 4-5 EL2 EL2
17-19 Green 1-3 EL1 EL1
20 Raw 0 EL0 EL0

Unit Morale and Troop Strength

Units that are demoralized (i.e., below their base Morale) often fight less effectively than normal. At the GM's option, the Troop Strength of demoralized units can be reduced or units whose Morale is above their base Morale may also have their TS increased. A unit's Troop Strength can be reduced (or increased) by 10% for each point their current Morale level is below (or above) their base Morale.

EXAMPLE - Due to poor leadership and some serious defeats, a Veteran Heavy Infantry platoon (30 soldiers with total TS of 225 and base Morale of +6) has an effective Morale of +4, the same as Average quality troops. This unit's TS could be treated as 180 until they can regain their base Morale level.

Changing Troop Quality

In a continuing campaign, units will lose troops and replace them -- sometimes with experienced men, sometimes with raw recruits. Keep track of the number of battles (not just days of battle) a unit fights, counting anything over 20 as 20. When a unit adds new men for any reason, the new Troop Quality is the new average experience of the men. GMs may not want to count battles where there was little resistance, such as engagements with odds of greater than 10 to 1.

EXAMPLE - Titus of Megalos commands a veteran unit, with average experience of 10 engagements. It has 87 men. Titus recruits 11 more men, of "green" quality. Average experience is computed as follows: 87 x 10 for the old troops. 11 x 1 (use the low end of the experience scale) for the new men.

870 plus 11 is 881. Divide that by 98 men, for an average experience of just under 9. Round down to 8. The company is now considered to have an average experience of 8 engagements, making it merely "seasoned." Two more fights will bring it back to "veteran" status.

Six months of military training will change Untrained troops into Raw quality. A year of training will turn Raw troops into Green. No further increases in quality can be made without actual battle experience.

Building and Feeding an Army

An army travels on its stomach, but it won't go very far if you don't pay it, either. The following sections gives costs for raising, feeding and paying troops.

Raising Troops

The cost to raise a body of troops is determined by troop type. The general method of determining this is to total the cost to purchase equipment and pay a hiring bonus. The hiring bonus is usually equal to a month's pay, or about 10% of the equipment cost.

GMs may modify costs for special circumstances, such as unusually good or bad availability of men, horses and equipment.

For ranged weapons, add the equipment cost and the difference in hiring bonus to the total, per man. The hiring bonus is usually considerably higher for trained missile troops because of their lower availability.

Normally, troops of Elite and Veteran quality cannot be "raised" -- there are not that many trained men currently unemployed, unless the GM decides that a mercenary unit is available.

The GM decides what sort of troops are available. PC leaders will usually want to raise the best troop they can, given their budget. If the GM needs to determine troop quality randomly, use the table above under Troop Quality and Morale.

NOTE - The following section is unconverted since I do not have book 1. If anyone has a good idea how much it costs to live at Station 1, let me know.

Paying and Maintaining Troops

The cost to feed and maintain an infantryman is equal to the cost of living for station 1; the cost to feed riding animals is generally the Station 1 cost of living times their AHP/10, round up. Particularly large animals (e.g., elephants) or those with expensive feeding needs (e.g., carnivores) will cost more; how much more is up to the GM. Troops must be fed, or a unit will revolt, dissolve or desert.

Troops also expect monthly pay; unpaid troops can be dangerous to their leaders or employers. Morale drops by 1 after the first missed payday, 2 after each succeeding missed payday. Make a Morale roll on each missed payday, after reducing morale. A failed roll gives bad results, as per the GM's whim. Every second payday made increases morale by 1, but only to the extent of eliminating the negative modifiers for previously missed paydays. Limit the Morale of Elite and Veteran units to 14 for determining the results of no pay.

Generally speaking, human troops expect to be paid about 10% of the cost-to-raise, each month, with the bonuses given in the Determining Troop Quality table for experience. An additional 50% bonus will increase morale by 1 for the next month; a 100% or more bonus will increase morale by 2 for the next month. Income from looting counts as pay. Troops may forego some pay, if the chances of substantial looting in the near future are high. If those chances are not fulfilled, though, the backlash from the troops could be much worse. In some eras, troops may be paid in lands, citizenship and other inducements.

Conscripts fighting against their will do not need to be paid, though some conscripted armies still do pay their soldiers (e.g. the U.S. Armed Forces during the Draft). Additional paid security forces will often be needed to keep unpaid conscripts from deserting. These forces should be better equipped than the conscripted forces to maintain order (e.g. the Republican Guard of Iraq during the Gulf War). Conscripted troops generally have lower morale than volunteers; -1 for paid conscripts, and -2 or lower for unpaid conscripts.

The Battle

This section describes the method for determining the outcome of the battle between the armies constructed in the previous section.

Special Abilities

In some settings, special abilities (magic, psionics and superpowers) can be used in warfare. Before rolling for catastrophes, resolve the effects of special abilities on the battle. For more details, see Exceptional Powers in Battle.


When the battle begins, the GM rolls 2d10 on the following table, once for each side, to see if something goes disastrously wrong.

Catastrophe Roll
2-7 No catastrophe.
8-10 Enemy manages some sort of surprise: -1 to Strategy roll.
11 Enemy receives unexpected reinforcements or is just lucky. Increase his Troop Strength by 10%. (The GM may be creative about what occurred.)
12 The battle plans have been partially revealed to the enemy by turncoats, spies, magic, etc.: -2 to Strategy roll.
13 Dissension among allies or top leaders weakens morale. -2 to Strategy roll, -1 to Morale of all units.
14 Enemy reveals a terrifying atrocity: -1 to Morale of all units if Morale roll is failed; +1 to Morale, in anger, if a 12+ Morale roll is made.
15 Ally or unit commander defects to enemy, revealing plans and taking his troops with him. Recalculate forces' Troop Strengths; -2 to Strategy roll.
16 Miscommunication reduces any special force advantage by 1/2 (round down).
17 An important unit leader (rolled randomly among leaders commanding at least 20% of that side's Troop Strength) is wounded early in battle (2d of damage): -1 to Morale of all units, -2 to Morale of his unit.
18 Commander wounded early in battle (2d of damage): -2 to Strategy roll, -3 to Morale of all units.
19 Important unit leader (rolled randomly as above) killed (or if a PC, wounded and unconscious) early in battle: -2 to Morale of all units, -3 to Morale of his unit. (If a PC, he makes no further Survival or Glory rolls.)
20 Commander killed early in battle (or if a PC wounded and unconscious). Base Strategy roll cut in half (round up). -5 to Morale of all units.

The Catastrophe table may be altered depending on the culture involved. For example, defections are more common than atrocities in Katai, so their positions in the above table could be switched.

Consequences to Player Characters

The more daring and brave a warrior is, the more likely he is to get hurt!

Each PC in a battle must make a Battle skill roll. Battle skill cannot be studied or taken as a beginning skill. It is equal to the average of the PC's CEL and the EL of his main weapon skill. If he uses both a melee and a missile weapon, base Battle skill on the melee weapon. Since the battlefield is a very dangerous place, no matter how careful or skilled a soldier is, Battle skill rolls are limited to +7. If the PC is rolling for survival at a penalty, due to Risk or being on the losing side, these modifiers are first applied to Battle skill before imposing the limit of +7. Therefore, PCs with Battle skill greater than +7 can still receive some benefit. Note Battle skill on the PC's record sheet in pencil, since it will change if he goes into battle with different weapons or if his CEL or Combat skills are improved.


A PC can choose to take more or less Risk in a battle, announcing his choice before his Survival roll. He may choose any number from -7 to +7 as a modifier, -7 being very risky and +7 being very cautious. This Risk modifier is applied to the Survival roll. However, the opposite modifier applies to his Glory roll. No guts, no glory! If Survival is -4, then Glory is +4.

Cowardly PCs and those PCs in units held in reserve or who otherwise were not exposed to the full impact of the battle, should not pick a Risk factor below -1. Overconfident PCs should not pick a Risk factor above +1. Berserk PCs should not pick a Risk above 0.

Survival Roll

If the Survival roll results in damage, take the injury directly off HT -- subtract Toughness. Determine hit location(s) randomly. If a PC unit or army leader takes enough injury to fall unconscious, his unit's final Strategy roll is affected as per Catastrophes (see above). A PC can use Luck to re-roll the Survival roll.

Roll Result
18+ Unhurt
13-17 1d3 damage
12 2d3 damage
10-11 2d6-AV damage
8-9 4d6-AV damage*
6-7 8d6-AV damage**
5- 12d6-AV damage***
*This result applies if you roll a natural 4 on the 2d10 **This result applies if you roll a natural 3 on the 2d10 ***This result applies if you roll a natural 2 on the 2d10

Glory Roll

A warrior who gains glory will have improved Reputation, and the associated reaction bonus, for the specified period. The indicated modifiers to the Strategy roll are used only if the PC is a unit leader. This Strategy bonus is 1 point higher (and any penalty is 1 point worse) if the PC is force commander. Roll for Glory even if the character dies -- a glorious death can inspire the troops.

Battle Skill Roll and Result

Roll Result
24+ Covered in glory; +2 to reputation for 1d6 months, +1 permanently; Roll for promotion; +2 to Strategy roll.@
19-23 Fought with great courage and heroism; +1 to reputation for 1d6-2 months (1 month minimum); roll for promotion; +1 to Strategy Roll
16-18 Fought heroicly: roll for promotion; +1 to Strategy.
12-15 Fought competently.
8-11 Fought Adequately.
4-7 Fought Poorly: -1 to Reputation for 1d6-2 month (1 month minimum); -1 to Strategy roll. Superior officer notices your ineptness or caution; make an influence roll to see how he will treat you after the battle. A failed result indicates a possible demotion in rank.*
3- Fought very badly; -2 reputation for 1d6 months; -3 to Strategy roll. Results from superior officer as above. In addition, if you survive the battle, someone your equal in rank will publicly name you a coward and, in some cultures, will try to provoke a duel. Demotion.**
@ This result applies if your roll a natural 19 or 20.
* This result applies if you roll a natural 3 or 4.
** This result applies if you roll a natural 2.

Some results may be different depending on the culture involved. For example, a loss of Reputation in Katai may cause a character to contemplate suicide.


Check the reaction of the character's superior officer after the battle, based on the character's improved Reputation (x10) plus his influence chance.

With a successful roll under 1/3rd the needed number (in some cultures), the character may be offered a battlefield promotion of one Rank. If the reaction is under 1/10th, the PC may also be offered a transfer to an elite unit. In any period or culture, a favorable reaction will dispose the superior to do the heroic warrior some favor; this may well consist of an especially dangerous and honorable position in the next battle.

Strategy Modifiers

The GM now takes into account the circumstances of the battle, which may raise or lower the effective Strategy skill of each side's commander. All these modifiers are cumulative.

Relative Troop Strengths

Compare the troop strengths of the opposing forces. Divide the greater TS by the lesser one for the "odds factor." For example, a TS of 100 vs. a TS of 50 is an odds factor of 2. The greater the odds factor, the greater the bonus to Strategy skill of the stronger force's commander.

Odds FactorStrategy skill bonus
1.2 or less No bonus
1.2+ to 1.4 +1
1.4+ to 1.7 +2
1.7+ to 2 +3
2+ to 3 +4
3+ to 5 +5
5+ to 7 +6
7+ to 10 +7
greater than 10 +8

When a force is more than 2 TLs higher than the opposing force, the 10 to 1 odds limit is waived for the higher TL army. Each additional 10 to 1 odds is equal to another +1 Strategy. For instance, when a TL 6 force is fighting a TL 3 feudal army, 30 to 1 odds would yield a +10 on the Strategy roll.

Defensive Position

If one side is clearly the defender, it gets Strategy modifiers based on its position. When appropriate, these modifiers are cumulative.

Attacker attacks downhill -3 or worse
Attacker approaches under cover -1
Attacker must come up a gradual incline +1
Attacker must come up a steep incline +2
Attacker must come up a steep incline on bad ground +3
*Attacker must force a narrow passage (defile, pass, ford, or bridge) +2 to +8, depending on how narrow it is.
*Defender is protected by palisade, breastwork, trenches, dry moat or unforded/unbridged river +3
*Defender occupies an unwalled town +2
*Defender occupies a walled town +5
*Defender occupies a manor, stronghold, unwalled city or fort +4
*Defender occupies a walled city +7
*Defender occupies a castle +9
* Reduce the value of any modifier with an asterisk (*) by 2 if the attacker has seige weapons or mining crews. Battles involving the starred modifiers use a different set of combat tables (see Resolving the Contest of Strategy).

These defensive factors can be combined. For instance, a castle on top of a steep hill would count as +11.

Special Unit Superiority

A force will receive a Strategy bonus if it has at least a 2 to 1 superiority in the numbers of certain troop types, regardless of troop quality. In a siege action all cavalry are counted as infantry. If the opponent has no troops of the equivalent type, treat as 5 to 1 or better. There are four types of superiority: artillery (only in siege situations); cavalry (only in non-siege situations); air (any situtation) and ranged weapons.

Other types of units, such as undead, can be considered special units at the GM's option.

Each type of superiority counts separately: if you have a force of mounted archers and the foe has no cavalry or missiles, you have 5 to 1 superiority in both missile weapons and cavalry. Ratios for determining superiority are rounded down.

Ratio Strategy skill bonus
2 to 1 +1
3 to 1 +2
5 to 1 or better +3

Neutralizing Special Units

Some types of units neutralize the superiority of the special units described above. For instance, pikemen can neutralize a cavalry charge. When figuring special unit superiority, count these neutralizing units as the same type as the special unit for the side with less of the special unit. Thus, pikemen cannot give you cavalry superiority, but they can neutralize the other force's superiority.

Special Circumstances

Add Strategy bonuses or subtract Strategy penalties for any of the following situations. All these circumstances are determined by the GM or the group's roleplaying; for instance, a unit is unsupplied if the GM says it is.

Taken totally by surprise -6
Partial surprise -- less than an hour's warning -2
Force-marched into battle -3
No supplies -3
Short supplies in a besieged city or castle -2
Supplied by forage only - 1
On home grounds +2 (not cumulative with Defensive bonus for village, temple, city, manor or other fortification)

GMs may give additional bonuses or penalties from -6 to +6 for other factors as they see fit: e.g., a heavy fog when trying to launch a closely coordinated attack might be worth -3.

Battle Plans

The GM should sketch a map of the battlefield (or perhaps of several, optional battlefields) for the players based on their armies knowledge of the area, especially if the PCs are unit or force leaders. The GM should then ask the players to give him a battle plan for their side (for both sides, if there are PCs on both sides or if there is an Adversary Player for the non-PC side). If the GM thinks a plan is especially good or bad, it deserves a Strategy roll bonus or penalty of from +3 to -3.

If the GM is playing the part of the adversary, he should occasionally spring a tactical surprise on the players. Describe what happens realistically. If they handle it well, they get a Strategy roll bonus; if they react poorly, they suffer a penalty.

Special Forces

If either side has the services of assassins, commandos, scouts or spies, their proper use can be an important part of the battle plan. Special forces like these may be sent on a variety of missions. The success of each mission depends on the number of personnel assigned and (in general) on the Stealth (or in some cases Tactics) skill of their leader. Special forces missions can be played out as whole adventures (see GURPS Special Ops), or abstracted into the general battle plan.

Assassination of the enemy leader will be a Catastrophe for the foe, if it works. But it's risky, and if it fails, the enemy's morale will be improved, especially if your spies are publicly executed before the battle!

Scouting the enemy forces is much safer and easier, and will usually give a + 1 or, if many commandos are used, a +2 on Strategy.

Security assignments can be given, to protect the lord and generals from opposing assassins, or to ambush and kill enemy scouts.

Other creative uses of spies should be encouraged and rewarded by the GM. If assassins are paid well and treated with respect, they will undertake almost anything.


A careful commander might consult diviners before a battle. The effectiveness of divination in general is known only to the GM . . . and even in a campaign where magic is real, an individual diviner may be a fake.

A general may have many diviners, but he must pick just one to believe. A genuine diviner who makes his skill roll gives +1 to his lord's Strategy roll, or +2 on a critical success. If the diviner is a fake, average his own Strategy roll with the commander's, unless the commander either fully accepts (use just the diviner's Strategy) or discounts the diviner's advice (use the commander's Strategy). The details of these modifiers, of course, must remain secret from the players.

Resolving the Contest of Strategy

After determining the opposing commanders' effective Strategy, a Quick Contest of Strategy is rolled to determine how well the troops are handled. (For battles involving a total of less than 200 men, Tactics skill may be used instead.)

The winner of the Quick Contest of Strategy is the winner of the battle. The difference in the rolls the commanders make will determine how decisive the victory is. Whether defeated troops withdraw in good order or rout depends on their Morale roll (see below). Refer to the appropriate table below to find the outcome. Use Tables B or C if any of the starred Defensive Position modifiers applied.

EXAMPLE - One leader makes a roll of 14, the other a 12. The difference is 2; the battle was inconclusive. If one leader makes a 14 and the other a 6, the difference is 8 -- a much more one-sided battle.

A. Open-Field Battle
Won byResult
0-4 Inconclusive battle. Each unit on both sides should make a 12+ morale roll. Those who succeed hold position. Those who fail by only 1-5 withdraw in good order. Those who fail by 6 or more rout.
5-9 Marginal victory. Each unit of the loser withdraws in good order if it can make a 12+ morale roll; otherwise it routs.
10-14 Definite victory. As above, but morale roll task is 15+.
15-19 Great victory. As above, but morale roll task is 18+.
20+ Overwealming victory: the loser routs.

B. Defender Wins
Won byResult
0-4 Inconclusive Battle. The attacker is thrown back but holds his former position. He may attack again on the next day, at -2 Morale.
5-9 Marginal victory. The attacker holds position if more than half its troops can make a 12+ morale roll; otherwise the whole force withdraws in good order.
10-14 Definite victory. As above, but morale roll task is 15+.
15-19 Great victory. Each attacking unit withdraws in good order if it can make a 12+ morale roll; otherwise it routs.
20+ Overwelming victory. As above, but morale roll task is 15+.

C. Attacker Wins
Won byResult
1-4 Inconclusive battle. The attacker technically won, but the defender will suffer no morale penalty on the nex day of battle.
5-9 Marginal victory. Both sides hold position. The defender will be at -2 morale on the next day of battle.
10-14 Definite victory. The defender holds position if more than half its troops can make a 12+ morale roll; otherwise the whole force withdraws*.
15-19 Great Victory. The attacker captures the position. Each individual unit of the defender withdraws* in good order if it can make a 12+ morale roll; otherwise tha unit routs or, if there is no escape, surrenders.
20+ Overwelming victory. The attacker captures the position and takes the enemy commander alive. Each individual unit of the defender withdraws* in good order if it can make a 15+ morale roll; otherwise that unit routs or, if there is no escape, surrenders.
*If defenders get a "withdraw" result and have nowhere to go, make a second morale roll for each such unit at +3 over the previous roll. A success means the unit holds position and another battle is likely. (these defenders probably have their backs to the wall or have retreated to an inner stronghold.) A failure means the unit surrenders. If surrender is not an option (no prisoners), the units will hold position and another battle is required.

Some outcomes on these tables may be modified by culture. For instance, losing Katai commanders in Table C who cannot withdraw will attempt suicide.


In an actual siege involving a defender within a walled city or castle, the above rules and Tables B and C only apply when the attacker storms the fortifications. The overall siege is a long, drawn-out affair, taking months or even years to complete. Many other tactics may be employed instead of an all-out assault, which tends to be very bloody. Cutting off supplies and water to the area and waiting for starvation, bribing someone to open the gate, catapulting diseased animal carcasses and firebrands, and infiltrating with spies are all alternate methods of taking a fortification.


Each unit starts with a Base Morale, determined by its Troop Quality. Campaign events can affect morale before the battle. Catastrophes affect morale for that battle only. Loss of established leaders affects morale until the force wins a clear victory; as long as the force is defeated, has inconclusive battles or marginal victories, the morale will stay low.

EXAMPLE - Titus of Megalos has a veteran unit -- base morale 15. Loot was good last month, so they entered the battle with a +1 morale, for a 16. In the first hour of battle, Titus was wounded (-1 morale). So effective morale is back to 15. After the battle, morale returns to 16.

Morale is used to determine whether a defeated unit withdraws in good order, or routs. The GM may also require a morale roll whenever a unit is asked to do something dangerous or unreasonable (e.g., fight at unreasonable odds, go without food, water or pay, scale a castle wall despite the fact that the defenders are dumping sewage over the walls, etc.).

Morale Modifiers

Bonus payments can increase morale (see Paying and Maintaining Troops).


Units, or even the entire force, may rout, fleeing in panic, on a very bad combat result (see Resolving the Contest of Strategy) and/or a failed Morale roll. If a unit routs, its casualties are increased. Whether a routed unit will ever reform as a unit is up to the GM. The survivors may be able to reassemble under a number of circumstances: the battle was in friendly territory, the unit was largely cavalry, there were plenty of places to hide, the leader is charismatic, etc. PCs whose units are routed (or totally crushed) must make their second Survival roll at -2 (see Second Survival Roll).


After the contest of strategy, casualties for each force are determined. This does NOT affect the PCs; their fates are determined by their survival rolls. Even if a PC's unit is entirely wiped out, a PC who makes his survival rolls gets away somehow.

Each unit makes a casualty roll, rolling 2d10 plus the strategy skill of its leader, minus 2d10 plus the strategy skill of the enemy force commander. If the unit was a defender proteced by his position (modifiers with a * under defensive position) they may add that to their total. If the unit was on the winning side, add 1/2 the combat difference (round down) to the roll. If on the losing side, subtract 1/2 the difference.

A unit's armor type (heavy, medium, light) moves them DOWNWARD on the casualty table.

Heavy Cavalry, Heavy Footman Adjust result down by 4 lines.
Medium Cavalry, medium footman Adjust result down by 2 lines.
Light Cavalry, light fotman, pikemen adjust level down by 1 line.
Town rabble no modifier.

If a unit routs, roll 1d6 and move up that number of lines. If any combat risk was applied, move up that many lines on the table.

If the GM thinks that the battle was particularly intense, the caualty results for all units for both sides may be moved up one or more lines.

Round all losses up. Half the casualties (round down) are killed or permanently maimed. The ther half recover at 5% of the original unit per day in camp, or 2% per day on march. If magic healing is available, add 1d% to the recovery rate. One healer is required for every 10 injured soldires to get this bonus.

Lost seige weapons become property of the victor; after an inconclusive battle, each side retains half its lost artillary and the others are considered destroyed.

Casualty Table
-19 or less (12d6+60)%
-17,-18 (11d6+55)%
-15,-16 (10d6+50)%
-13,-14 (9d6+45)%
-11,-12 (8d6+40)%
-9,-10 (7d6+35)%
-7,-8 (6d6+30)%
-5,-6 (5d6+25)%
-3,-4 (4d6+20)%
-1,-2 (4d6+15)%
0 (4d6+10)%
1,2 (4d6+5)%
3,4 (4d6)%
5,6 (3d6)%
7,8 (2d6+2)%
9,10 (2d6)%
11,12 (1d6+2)%
13,14 (1d6)%
15,16 (1d3)%
17,18 (1d2)%
19 or more 0.5%, rounded down

Second Survival Roll

Any PCs on the losing side of a battle must make a second Survival roll, using the same Risk modifier as for the first roll. Adjust this roll down by -1 for every 3 full points of difference in the Contest of Strategy. If defending, adjust up by any bonus for starred Defensive Position modifiers. If the PC's unit was routed (see Rout), the second Survival roll is made at -2. Any adventuring after that will be directed, at least for a time, toward getting home alive or regrouping with other lost battle comrades.

Roleplaying Battle Scenes

The system presented here will resolve large combats. It is up to the GM to make these interesting for the players -- and vice versa. The GM should always sketch a map of the battlefield (or perhaps of several optional battlefields) to help the PCs visualize the strategy, especially if they are unit or force leaders.

Players whose characters are in leadership positions may attempt to give orders to their troops once the battle has started and any enemy surprises have appeared. PCs who are mere troopers can control only their own fates -- and then, only to a limited extent -- by deciding how much bravery (or cowardice) they will show. But they should describe their actions anyway: not just "I'm going for a -3 on Survival to get a +3 on Glory" but "I'm shouting insults and charging the enemy standard-bearer."

Similarly, the GM should present all morale effects with maximum drama -- during preparations for the battle, at the beginning of battle and when the troops begin to rout.

Remember: roleplaying should be fun. Players should be heroic; after all, each character thinks of himself as the hero of his own story. GMs should remember that they are storytellers; tell the tale well, and reward heroism.

After the Battle

When the battle is finished, there will be opportunities for looting, ransoming prisoners, and regrouping forces.


Many military units -- not just mercenaries -- depend largely on loot to make life worthwhile. The loot available in even a burned-out and picked-over city can be immense and is up to the GM to settle.

But the loot from a battlefield is also very valuable. The force that holds the field after a fray will be able to recover the arms and armor of all its own casualties, and most, if not all, of the other side's dead. If the foe routed, both its dead and wounded -- all its casualties -- will be left for looting.

Very roughly speaking, the average value of the gear stripped from a killed or captured trooper would equal 1/3 of the cost to "raise" that trooper (see Raising Troops). It would sell for less -- possibly only 20% of that cost, in cash -- but to an army, most or all of the salvage will be useful. Halve these numbers again for cavalry; live horses are expensive, dead ones are rations at best.

Some cultures (e.g., Katai) did not make a practice of looting the battlefield for many reasons. Other cultures may take trophies, such as heads, from their dead enemies. Battlefields were often looted by the locality's poor (bandits or peasants) before the relatives of the dead could make arrangements for burial. Sometimes such scavengers also found soldiers who had been left for dead by their comrades and enemies. In such a case, check the scavenger's reaction roll; he might kill the soldier, ignore him or nurse him back to health.

PCs who have been wounded, or even those who thought themselves dead, may wake up in a peasant's cottage, in the enemy camp, in prison, or as slaves.

Ransom of Prisoners

Especially in aristocratic societies, it can be highly profitable to take a noble foe as a prisoner rather than slay him outright. Many such lords would carry a ransom of hundreds, if not thousands, of coin.

Some cultures did not hold captured enemies for ransom. They may be either executed, held as hostages for their relatives' good behavior or held for some other fate.

Multiple Combatants

Most battles are fought between two sides, though many individual allies may be on each side. If more than two forces are fighting independently from each other, a multi-party Contest of Strategy can be used with the commander who wins by the greatest margin holding the field, while the others take the effects from the tables based on their difference from the winner. In this case, the Relative Troop Strength Strategy bonus is figured against the average of the other opponents' TS.

Exceptional Powers in Battle

Combat in many settings can be affected by exceptional abilities, like magic and powers. These powers can be used directly, such as hurling fireballs at enemy troops, or more subtly, such as disabling enemy leaders, scouting enemy forces, or bringing a single morale-shaking disaster to the enemy. Supers with powerful offensive and defensive capabilities should fight as soldiers, using the Troop Strength section to calculate TS. Those supers with less battle-oriented skills, along with mages and psis, should use this section to determine their effect on the battle.

Determining Exceptional Power Available

To determine the exceptional power available to the troops, a Exceptional Strength (ES) must be calculated for each practitioner.

Computing Exceptional Strength

Compute the Exceptional Strength (ES) for each force by computing the total of MEL and all ELs (plus 1 per spell known) of each practitioner. If the total is less than 15, the practitioner is not strong enough to affect a mass combat. If the total is 16 or more, use the following table.

16 points = 1/2 Exceptional Strength point
24 points = 1 Exceptional Strength point
32 points = 2 Exceptional Strength points
40 points = 3 Exceptional Strength points
48 points = 5 Exceptional Strength points
56 points = 8 Exceptional Strength points
64 points = 12 Exceptional Strength points
72 points = 16 Exceptional Strength points
80 points = 20 Exceptional Strength points
Add 1 Exceptional Strength point for each additional 2 points.

Exceptional Strength Modifiers

Mage possesses enchanted item: +1 to +5 (GM's discretion)

Using Exceptional Powers on the Battlefield

Each player secretly and simultaneously marks the number of points expended on each special effect detailed below (including defense -- see Defending Against Hostile Powers below), after the Troop Strength of both forces have been calculated, but before they are revealed or any die rolls are made.

To use a specific effect, a practitioner must have some power or spell that could produce the desired effect. If all the mages available have no Healing spells, they can not perform battlefield Healing effects. The GM can determine which effects are possible for each side.


Special powers can attempt to force a Catastrophe (see above) on its opposition by increasing the opponent's Catastrophe roll. Each 2 points expended, will give the foe a +1 modifier on its Catastrophe roll.

Affecting Morale

Exceptional powers can be used to improve the morale of friendly units, or to reduce the morale of enemy units. In either case, one point provides a +1 (or -1) morale modifier for 100 TS of troops. Thus, for example, a unit of 20 Green Heavy Infantry (Total TS 100; Morale roll of 11+) can have its morale modified by +2, giving them the morale of Average troops (13+), or -2, lowering their morale to that of Raw troops (9+), for an expenditure of 2 points.


Exceptional powers can be used to improve the survival chances of injured troops. One Exceptional Strength point can adjust the result on the Casualty Table down by one line for 100 TS of troops. This option counters and is countered by "Striking against the Foe" below.


Exceptional powers can be used to observe enemy forces, and to thereby reduce the effectiveness of an enemy's strategy. If the force with the exceptional individual is being run by the player, successful use of scouting powers will give him some advance warning of the preparations used by the enemy, and allow him to revise his battle plan (GM's discretion as to how much).

If the force is being run by an NPC, abstract this information to a +1 Strategy modifier, costing 3 Exceptional Strength points. More energy can be expended if desired (particularly if the enemy has special defenses), but no more than a +1 modifier can be gained in any case.

Confounding the Enemy

Special powers can also be used to disrupt the enemy's battle plan. If the force leader knows the enemy battle plan (through diviners, scouting magic or more mundane means), or if he just wants to guess, he can use the exceptional abilities to create conditions adverse to the enemy's plan. Such efforts include flooding a river to be forded, bringing up a dense fog, or even causing an earthquake in a narrow defile.

To do this, the player of the force should describe the effect, and how it would be produced (what spell or psionic skill would be used, etc.). The GM should analyze the effectiveness of the strategy and assign an appropriate Excep-tional Strength cost and Strategy roll modifier.

Striking Against the Foe

Rather than providing unique capabilities, many of these powers can simply be hurled against the foe. These special powers can be powerful weapons, and have made the difference between defeat and victory in more than one battle of myth or science fiction. Each Exceptional Strength point can adjust the result on the Casualty Table up by one line for 100 TS of troops.

Defending Against Hostile Powers

Exceptional Strength points can be allocated to defend against hostile powers.

These points are not allocated to other specific effects; rather, they are used to block other effects after the allocations are revealed.

Each point of power allocated to defense blocks 1 point of the opponent's offensive power. Exceptional powers must be blocked in units. It is not possible, for example, to block only 1 enemy ES point allocated to Catastrophe modifiers; these must be blocked in units of 2.

Should more points be allocated to defense than the other side allocated to offensive capability, all of the opponent's power is blocked, but the remainder of the defensive points are wasted.

This ends the "mechanical" portion of mass combat. Dealing with the outcome in terms of the campaign is left to the GM and the players. Below is a completely worked out battle and two examples of these rules: the armies of Yrth and World War I.

Troop Costs

NOTE - Unconverted, but retained so that once the lowest level is determined we can use ratios to find the rest.

The cost to raise troops is as follows, per man:

Heavy Cavalry $14,000
Medium Cavalry $9,000
Light Cavalry $5,000
Irregular Cavalry $3,000
Heavy Infantry $9,000
Medium Infantry $5,000
Pikemen $2,000
Light Infantry $1,500
Irregular Infantry $200
Small Siege Engines $15,000 average -- varies widely, includes armor.
Large Siege Engines $25,000 average -- varies widely, includes armor.

Add $500 per man if the troops are slingers, $1,000 for ordinary archers, $1,500 for archers with composite bows, longbows or crossbows.

The cost to maintain a soldier in the field is $200; to maintain a knight and horse costs $800. Monthly pay is expected to be equal to 10% of the cost to raise listed above, regardless of experience.

Non-Human Races

Treat as Irregular Cavalry (IC) of Average or better quality. Centaurs are tribally organized. Racial TS modifier is +2.
Always Medium or Heavy Infantry (MI and HI) of Seasoned or better quality. Dwarves are also supreme miners, and Dwarvish MN troops have a TS of 10 in a siege, and TS of Medium or Heavy Infantry in open battle. Use either modern or Classic Greek organization. If the Dwarvish mountains are attacked, all adult dwarves, male and female, would fight, fielding a powerful force. Racial TS modifier is +1.
Light Infantry or Cavalry composite or long bowmen (LI or LC), usually of Seasoned or better quality. In their home territory, elves are the consummate guerrilla warriors. Feudal organization is used by the elves. Because of their racial Combat Reflexes, Elves cannot be Irregulars. Racial TS modifier is +0.
Usually Medium Infantry (MI) of Average or better quality. They can throw rocks like a small siege engine and they can thus be counted as such. Giants are tribally organized. Racial TS modifier is +11.

Burton Choinski

Based on Generic Land Battle Rules by Brett Slocum