Mass Combat

masscombat.jpg Sooner or later, even the most peaceable kingdom will find itself faced with the prospect of war. While some nations might be willing to compromise, others are not amenable to negotiation or respond to overtures of appeasement with ever-increasing aggression. When diplomacy fails, the clash of steel is close behind.
     This section contains rules for kingdom leaders to create armies, assign their commanders, and prepare them for battle. These rules provide an abstract, narrative mass combat system that will let PCs rapidly play out a complex battle scenario without getting bogged down in excessive detail, while retaining fidelity to strategy, tactics, and realities of the battlefield. They are not intended to accurately represent complex wars, provide a highly tactical simulation, or precisely model a tactical warfare miniatures game.

Army Statistics

The description of each army is presented in a standard format, as explained below. These are tracked on a army sheet, like a character’s statistics are on a character sheet.

Name: This is the name of the army. This could be anything from a mercenary company’s name, such as “Thokk’s Bloodragers,” to a formal regiment number such as “7th Royal Cavalry,” to an informal name such as “militia from Redstone.”

XP: This is the XP awarded to PCs if their army defeats this army, and is the same as an XP award for an encounter with a CR equal to the army’s ACR (see below).

Alignment: An army’s alignment has no effect on its statistics, and is just a convenient way to summarize its attitude with two letters. It is usually the same alignment as a typical unit in that army.

Size: The army’s size determines not only how many individual units exists in the army, but also the army’s ACR and bonus hitpoints. Creatures of Large size or larger are treated as having an army of one size category large while creatures of Tiny size or smaller are treated as being one size category smaller when determining bonus hitpoints. If the army is cavalry, only use the mount’s size if the mounts are of higher CR than the riders.

Army Sizes

Army Size No. of Units Bonus HP ACR
Fine 1 +0 CR of individual creature -8
Diminutive 10 +1 CR of individual creature -6
Tiny 25 +2 CR of individual creature -4
Small 50 +5 CR of individual creature -2
Medium 100 +10 CR of individual creature
Large 200 +20 CR of individual creature +2
Huge 500 +50 CR of individual creature +4
Gargantuan 1,000 +100 CR of individual creature +6
Colossal 2,000 +200 CR of individual creature +8

Type: This lists the nature of the army’s individual units, such as “orcs (warrior 1)” or “trolls.” These rules assume all units in an army are essentially the same; if an army of 100 orc warriors 1 (meaning 1st-level warriors) actually has a few half-orc warriors or some orc barbarians, their presence has no effect on the army’s statistics. If an army has a large number of units that are different than the typical unit in that army, and these differences are enough to change the army’s stat block, it is generally best to treat the group as two separate armies with different stat blocks.

hp: An army’s hit points equal its ACR x the average hp value of 1 HD of the army’s units (3.5 for d6 HD, 4.5 for d8 HD, 5.5 for d10 HD, and 6.5 for d12 HD) plus a certain number of bonus hit points based on the army’s size as listed on the table above. For example, warriors have d10 HD, so an ACR 1 Medium army of warriors has 5.5 × 1 = 5.5 hp, rounded down to 5 hp, plus 10 hp for being Medium-sized, for a total of 15 hp. Note that only damage from other armies can reduce an army’s hp; a non-army attacking an army is mostly ineffective, though you can treat the attacker as a Fine army if you want to determine the outcome of the attack. As with standard game effects that affect hit points, abilities that reduce hp damage or healing by half (or any other fraction) have a minimum of 1 rather than 0.

Army Challenge Rating (ACR): This is based on the CR of an individual unit from the army and the army’s size, and scales like CR for monsters. To determine ACR, see the table above and apply the modifier for the army’s size to the CR of an individual unit in the army. If the army is cavalry, use the mount’s CR or the rider’s CR, whichever is higher. For example, an individual orc warrior 1 is CR 1/3, so a Medium army of 100 orc warriors 1 is ACR 1/3; a Huge army of 500 orc warriors 1 is ACR 3 (4 steps greater than the standard 100-unit army). If the group’s ACR would be lower than 1/4, it doesn’t count as an army— add more troops until you reach an ACR of 1/4 or higher.

Defense Value (DV): This is a static number the army uses to resist attacks, much like an individual creature’s AC. The army’s DV is equal to its ACR + 10 + any bonuses from fortifications or a settlement’s Defense score.

Offense Modifer (OM): This is a modifier added to a d20 roll to determine the army’s chance of success, much like an individual creature’s attack bonus. The army’s OM is equal to its ACR. If the army has the ability to make ranged attacks, that’s mentioned here. Melee attacks and ranged attacks use the same OM unless an ability says otherwise.

Tactics: These are any army tactics the army has at its disposal.

Resources: These are any army resources the army has its disposal.

Special: This section lists any special abilities the army has. Though most recruited units are warriors or fighters, you may be able to recruit an army of paladins, clerics, or other characters with abilities useful in mass combat. You might even be able to recruit monsters, whether humanoids such as goblins, trolls, and orcs, or exotic creatures such as centaurs and worgs. These creatures could have monster special abilities applicable to mass combat. A typical kingdom doesn’t have access to monster armies unless it has formed alliances with such creatures, either through formal Diplomatic edicts or befriending them during adventures.

Speed: This number indicates how many hexes the army traverses in a day’s march. Marching through difficult terrain halves the army’s speed. You can use the table on Movement and Distance in the Core Rulebook to determine the army’s speed based on the speed of its individual units.

Morale: This number represents how confident the army is. Morale is used to determine changing battle tactics, whether or not an army routs as a result of a devastating attack, and similar effects. Morale is a modifier from -4 (worst) to +4 (best). A new army’s starting morale is +0. Morale can be further modified by the army’s commander and other factors. If an army’s Morale is ever reduced to -5 or lower, the army disbands or deserts and you no longer control it.

Consumption: This is how many Build Points (BPs) an army consumes each week (unlike most kingdom expenses, this cost is per week, not per month), representing the cost to feed, hydrate, arm, train, care for, and pay the units. An army’s case Consumption is equal to its ACR divided by 2 (minimum 1). If you fall behind on paying the army’s Consumption, reduce its Morale by 2; this penalty ends when you catch up on the army’s pay.

Commander: This entry lists the army’s command and the commander’s Charisma modifier, ranks in Profession (soldier), and Leadership score. The commander must be able to communicate with the army (possibly using message spells and similar magical forms of communication) in order to give orders or provide a bonus on the army’s rolls.

Battle Phases

Mass combat takes place over the course of three battle phases: the Tactics phase, the Ranged Phase, and the Melee Phase. A phase doesn’t denote a specific passage of time, leaving the GM latitude to determine how long a mass combat takes to resolve. For example, a battle in a muddy field after a rain could take place over hours and involve several short breaks to remove the dead from the battlefield, but still count as one battle for the purposes of these rules. If there is an extended break (such as stopping at nightfall to resume combat in the morning) or the battle conditions change significantly (such as the assassination of a commander, the arrival of another army, and so on), you should treat each period of combat between armies as one battle. The battle phases are as follows:

Step 1— Tactical Phase. The GM decides what battlefield modifiers apply to the battle. Each army then selects which Strategy Track it will use during the battle. Strategies adjust the army’s DV, OM, and damage modifier as shown on the table below. Each army’s commander then makes a Profession (soldier) check. Starting with the lowest result, each leader reveals the Strategy Track he has chosen. The best result reveals last. A commander with a higher check can change his strategy in response to his opponent’s, though moving strategy more than one step on the Strategy Track table requires a DC 20 Morale check to execute successfully. If this check fails, the army’s current strategy doesn’t change. Adjusting an army’s strategy by one step in either direction does not require a Morale check and succeeds automatically.

Strategy Track

Strategy DV OM Damage Dealt
Defensive +4 -4 -2
Cautious +2 -2 -1
Standard +0 +0 +0
Aggressive -2 +2 +1
Reckless -4 +4 +2

Actual combat is effectively simultaneous, so going first is irrelevant and enemy armies can destroy each other in the course of a combat round.

Step 2— Ranged Phase. In this phase, two armies are arrayed near one another but have not yet advanced to commence the battle in earnest. Armies cannot attack in melee but can attack with ranged weapons or other abilities that allow them to attack at a distance. During the Ranged phase, each army can attack (provided it has the ability to make ranged attacks), advance (move up to engage the enemy in close combat), or hold (remain in place, neither attacking nor advancing). An army that advances can then attack in the Melee phase. Armies that do not advance cannot attack in the Melee phase unless they themselves are attacked by an enemy unit that advances.
     Some battlefields contain impassable barriers between armies, such as a river or cliff. In this situation, armies may be unable to advance during the Ranged phase unless they have some means of circumventing the barrier. An army inside a Fort, Watchtower, or fortified settlement with City Walls or a Moat does not count as having an impassable barrier between itself and enemy armies; instead, the Defense value of the fortification is considered to represent the difficulty of approaching to attack. Armies may stay at range and attack with ranged weapons, but armies using the advance action are considered to be attempting to scale the walls or otherwise assault the fortification in such a way as to threaten the safety of the defending army.
     Friendly Fire: When an army makes a ranged attack against an enemy army that is engaged with one of your armies, it has a 25% chance of dealing 1d4 points of damage to the allied army regardless of whether its attack is successful. If your ranged attack roll is a natural 1, your allied army automatically takes 1d4 points of damage, while on a natural 20 your allied army never takes damage from friendly fire. An army taking damage from friendly fire loses 1 point of Morale.

Step 3— Melee Phase. The armies finally clash with melee attacks. The commanders each select a tactic their respective armies will use during the battle, then each army makes an attack against another army. Repeat the Melee phase until one army is defeated or routs, or some other event ends the battle.
     Once each Melee phase after the first, the commander can alter the army’s strategy. Adjusting the strategy 1 step up or down is automatically successful and doesn’t require a check. If the commander want to adjust strategy more than 1 step, the army attempts a DC 20 Morale check. Success means the strategy changes to the desired level. Otherwise, the army’s current strategy doesn’t change.

Attacking and Taking Damage

In mass combat, the hundred of individual attacks that take place in one battle phase overlap each other enough that who actually attacks first is irrelevant.
     When armies attack, each army attempts an Offense check (1d20 + the attacking army’s OM) and compares the result to the target army’s DV. If the Offense check is equal to or less than the target army’s DV, the army deals no damage that phase.
     If the Offense check is greater than the defender’s DV, the defending army takes damage equal to the result of the attacker’s Offense check minus the defender’s DV. For example, if the attacker’s Offense check is 11 and the defender’s DV is 7, the defending army takes 4 points of damage. Because these attacks are resolved simultaneously, it is possible that both armies may damage or even destroy each other in the same phase.
     If the Offense check is a natural 20, but that check is lower than the enemy army’s DV, the attacking army still deals 1 point of damage. If the Offense check is a natural 1, that army can’t attempt an Offense check in the next phase, due to some setback: a misheard order, getting stuck in the mud, and so on.

More Than Two Armies

These rules can also serve in battles where more than two armies clash. In such battles, when your army attempts an Offense check, you choose which enemy army (or armies if you have multiple armies in the field) it is attacking and apply damage appropriately. On each phase, you may change which army you are targeting. If your kingdom fields multiple armies in a battle, you may want to divide responsibility for these armies among the players to speed up play.


A rout is a chaotic and disorderly retreat of a defeated army from a battlefield, usually from fear or when overwhelmed by a superior opponent. If an army’s hit points are reduced to a quarter of its maximum or less, its commander must attempt a DC 15 Morale check. If the check fails, the army scatters and retreats from battle. If it cannot retreat, it surrenders and is captured. When an army routs, all armies in the battle can attempt one final Offense check at the fleeing army as a parting shot before it escapes. (Normally, only enemy armies do so, but an aggressive or evil army might strike at a fleeing allied army out of anger or frustration.)
     Mercenaries: When a mercenary army’s Morale drops to -1, or when they have lost more than half their hit points, they must make a Morale check to avoid routing. A kingdom takes no penalties when a mercenary army disbands or is destroyed.

Victory, Rout, or Defeat

An army is victorious if all of its enemy armies flee the battlefield or are defeated. The aftermath of the battle can be different for each army, and depends on whether it was defeated, routed, or victorious.
     Defeated: If an army’s hit points are reduced to 0, it is defeated. A defeated army may have a few survivors, but they are so demoralized and wounded (and probably captured by the enemy) that the army no longer exists as a cohesive unit and can’t be used again in mass combat. If your army is defeated, reduce your kingdom’s Economy, Loyalty, and Stability according to the size of the army as follows:

Army Size Economy Loyalty Stability
Fine 0 0 0
Diminutive 0 -1 0
Tiny -1 -1 0
Small -1 -1 -1
Medium -2 -2 -2
Large -3 -2 -2
Huge -4 -2 -2
Gargantuan -4 -2 -3
Colossal -4 -3 -3

     Routed: If the army routs, reduce its Morale by 1. If the army’s current hp is lower than the army’s ACR, increase its hit points to its ACR. A routed army refuses to fight until you succeed at a Loyalty check during your kingdom’s Upkeep phase (you may attempt this check once per turn). Note that a routed army can still be attacked by enemy armies, and can attempt Offense checks in battles in return— it just can’t initiate a battle.
     Victorious: If your army is the last one left on the battlefield (not counting other friendly armies), it is victorious. Each time an army wins a battle, you can attempt a Loyalty check against your kingdom’s Control DC. If you succeed at this check, your army learns a new tactic and its Morale increases by 1 (to a maximum of Morale +4). If the army’s current hit points are lower than the army’s ACR, increase its hit points to its ACR. You may attempt a second Loyalty check; if you succeed, the army’s commander learns a new boon, to the maximum dictated by his level or ranks in Profession (soldier).


Each day that an army spends at rest (no movement and no battle), it heals a number of hit points equal to its ACR. Once per day, you may attempt a Loyalty Check against your kingdom’s Control DC. If you succeed, your army heals a number of additional hit points equal to its ACR. An inactive army heals back to its full hit points after a single month, no matter how many hit points it lost.
     The mass combat rules assume that this healing is a combination of actual wound healing and gaining new units to replace those who were killed (meaning you don’t have to track individual losses and resize armies). These units can be recruited from sympathetic locals, replacements from your own settlements, or forced conscripts from conquered lands. If circumstances make these replacement options unavailable or unlikely, the GM is free to limit how much an army can heal, generally to half the army’s normal hit points.

Mass Combat

Rise of Nations sephirothnomiko