Improved Mass Combat Rules (Part 2: Basic Rules) | Rules Supplement for Dungeons & Dragons Fifth Edition

Continuing on the rules that I playtested this last Saturday, this article covers the rules for improved mass combat in Dungeons & Dragons Fifth Edition.

This is an attempt to improve upon the mass combat rules that Wizards of the Coast released a while back, which is a little too simplified for its own good and kinda blah.

Playtest Content

The material here is presented for playtesting and to spark your imagination. These game mechanics are in draft form, usable in your campaign but not refined by final game design and editing. They aren’t officially part of the game.

Constructive feedback is welcome and appreciated in either comments or social media. If you can give me a valid reason with examples why something is off, 9/10 I’m likely to make changes to the content and credit you for doing so. Otherwise, feedback without anything to back it up gets ignored (or at most a smile emoji like this 🙂 ) Thanks!

Design Notes

Here are my notes for this build.

Before the Build

First and foremost, I want to make sure that the rules here don’t change the overall rules of Dungeons & Dragons Fifth Edition too much. It’s still a d20 system and uses the move/action combat system that Fifth employs.

In addition, I don’t want it to be a monstrous dice fest either. Instead of rolling for each individual creature, you instead roll for units.

The part that will take the longest amount of prep for the Dungeon Master will be creating the units themselves, so I think I’ll add in a supplement to this when I’m done that covers most of the “basic” unit types.

I probably need to incorporate some sort of “point system”, too.

For the rest of my notes on this build, you can read the introduction I wrote last night.

After the Build

I went through the entire 9th chapter of the PHB to build the notes out. You’ll notice a lot of similarities here in the rules.

The purpose of the unit damage and unit hit points rules is to greatly simplify unit damage for bookkeeping reasons. Otherwise, GMs and players alike will go crazy trying to work everything out.

I threw a couple other details that seemed to make sense such as a unit that misses and doesn’t have disadvantage still does some damage on a miss.

Heroes can challenge commanders so that the barbarian with the sucky Charisma score can run up and fight a boss one on one.

Originally, most creatures weren’t going to have a way to attack units, but I didn’t think that made a lot of sense (you’re telling me a purple worm can’t gobble up an entire unit of goblins?) so I added in a “mass attack” rule that allows bigger creatures to deal big damage.

Since I wrote roughly 7,500 words for this article, I’ll just let you read it and let me know what you think.

Errata

  • 1/28/2019: Reduced the damage to individual units by half (x20 on a hit and x10 on a miss) and removed the mob rules for auto hits with an 18. Also, I added in units with advantages to attacks deal double unit damage on a hit and normal unit damage on a miss.
  • 1/28/2019: Fixed area of effect damage so that it deals the spell or effect’s damage divided by 5 and not by 8.
  • 1/29/2019: Instead of a hero commanding a number of units equal to its Charisma modifier, I changed it so a hero can command a number of units equal to its proficiency bonus.

Mass Combat Rules

The optional rules in this article pertain to running large scale combats with dozens, if not hundreds of combatants.

Units and Heroes

In a mass combat encounter, there are two main types of participants: units and individual creatures.

Unit. A unit consists of eight creatures of the same type. The type of creature that makes up the unit is known as the base creature. In order to create a unit, you must add the mass combat unit template to the base creature, detailed below.

Individual creature. An individual creature is a character or monster that operates by itself on the battlefield. Some individual creatures may become heroes. Huge and Gargantuan creatures can only be individual creatures and may not create units.

Hero. A hero is an individual creature that moves and takes actions in initiative order without requiring an issued command. All characters are heroes. The GM may also run heroes on the opposing forces made up of commanders, specialists, and other independent NPCs and monsters. All legendary monsters are heroes.

Siege Weapons. In addition to units and heroes, armies can also employ siege weapons in mass combat. Siege weapons include trebuchets, catapults, ballistas and other weapons that deal heavy damage at long range. Siege weapons count as individual creatures.

Mass Combat Unit Template

Any Large or smaller non-legendary creature in Fifth Edition can become a unit. The following characteristics change or are added to a creature that becomes a unit.

Size. When it becomes a unit, the base creature’s size changes as follows:

  • If the base creature is Tiny, the unit’s size is Small.
  • If the base creature is Small or Medium, the unit’s size is Large.
  • If the base creature’s size is Large, the unit’s size is Gargantuan.

Armor Class. The unit uses the same AC as the base creature.

Hit Points. The base creature has unit hit points instead of normal hit points. Unit hit points equal the base creature’s hit point average divided by 5, rounded down (minimum of one). For example, a unit of Ogres would have 11 unit hit points (59/5 = 11).

Speed. The unit’s speed is the same as the base creature’s.

Ability Scores. The unit’s ability scores are the same as the base creature’s.

Initiative Score. Units have their own initiative score

Morale Bonus. A unit gains a morale modifier which is a number added to the d20 roll made to prevent unit’s from breaking during combat. A unit’s morale modifier is equal to the base creature’s Wisdom modifier + its current unit hit points + any one hero within 30 feet’s Charisma modifier (if any).

Saving Throws. The unit’s saving throw modifiers remain the same as the base creature’s.

Skills. The unit’s skill modifiers remain the same as the base creature’s. If an ability check would normally gain benefits from the Help action, the unit automatically receives advantage on the check. For example, if a unit is trying to knock down a barred door, it makes its Strength check with advantage.

Vulnerabilities, Resistances, and Immunities. The unit maintains all of the base creature’s vulnerabilities, resistances, and immunities.

Senses. Any special senses that the base creature has the unit has as well. In addition, the unit is always considered to have advantage on its Perception rolls. The base creature’s passive Perception increases by +5.

Languages. The unit’s languages are the same as the base creature’s.

Challenge. Units do not have a traditional challenge rating. If a unit is used outside of a mass combat encounter, reference the Creating a Monster rules in chapter 9 of the DMG for details.

Traits. The unit keeps any traits that the base creature has. However, some of the effects may be altered (details forthcoming in a future article).

The unit gains the Unit trait as follows (be sure to change the size and creature type):

Unit. The unit can occupy a Medium or smaller creature’s space and vice versa, and the unit can move through any opening large enough for a Medium drow. The unit can’t regain hit points or gain temporary hit points, and if the unit has half its unit hit points or fewer, it makes its attacks rolls, ability checks, and saving throws with disadvantage.

Spellcasting and Innate Spellcasting. Units cannot cast spells except for cantrips.

Multiattack. If the base creature has multiattack, the unit also has multiattack.

Attacks. The unit keeps the base creature’s attack bonus. If using a ranged weapon, the range remains the same. A Large unit’s melee reach is 10 feet and a Gargantuan unit’s reach is 20 feet. The unit can target one creature or unit within reach or range.

A unit may also make a melee attack against any hostile creature that is sharing the same space as the unit.

Attacks are made by rolling to hit as normal. On a hit, the unit deals its unit damage (see below). On a miss, the unit deals half its unit damage (rounded down). If rounding down would reduce the unit’s damage to 0, the attack has no effect.

Damage. Instead of rolling for damage, a unit deals unit damage when attacking another unit. Unit damage is equal to the base creature’s normal average damage for the attack divided by 5 (minimum of one). For example, a Gargantuan unit of ogres would deal 2 bludgeoning unit damage with its great clubs (13/5 = 2).

If the attacking unit targets an individual creature, fortification, or siege weapon, it deals damage equal to its unit damage times 20 on a hit. On a miss, the unit deals damage equal to its unit damage times 10.

Actions. Any extra actions or reactions that the base creature has may or may not be included with the unit’s actions depending on the action or reaction’s effect.

Sample Unit

This unit’s statistics presented here use a drow as a base creature.

drow-army

Drow Unit

Large unit of Medium humanoids (elf), neutral evil


Armor Class 15 (chain shirts)

Unit Hit Points 2

Speed 30 ft.


Abilities Str 10 (+0), Dex 14 (+2), Con 10 (+0), Int 11 (+0), Wis 11 (+0), Cha 12 (+1)


Skills Perception +2, Stealth +4

Senses darkvision 120 ft., passive Perception 17

Languages Elvish, Undercommon


Fey Ancestry. The unit has advantage on saving throws against being charmed, and magic can’t put the unit to sleep.

Unit. The unit can occupy a Medium or smaller creature’s space and vice versa, and the unit can move through any opening large enough for a Medium drow. The unit can’t regain hit points or gain temporary hit points, and if the unit has half its unit hit points or fewer, it makes its attacks rolls, ability checks, and saving throws with disadvantage.

Sunlight. While in sunlight, the unit has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.


Actions

Shortswords. Melee Weapon Attacks: +4 to hit, reach 5 ft., one unit or target in reach or one target in the unit’s space. Hit: 1 piercing unit damage or 20 piercing damage if the target is a creature. Miss: 0 unit damage or 10 piercing damage if the target is a creature.

Hand Crossbows. Ranged Weapon Attacks: +4 to hit, range 30/120 ft., one unit or target within range. Hit: 1 piercing unit damage or 20 piercing damage if the target is a creature, and the target must succeed on a DC 13 Constitution saving throw or be poisoned for one hour. If the target is a creature, it automatically fails its saving throw. If the saving throw fails by 5 or more, the unit or creature falls unconscious. Miss: 0 unit damage or 10 piercing damage if the target is a creature and the creature must make the aforementioned saving throw.

 

The Order of Combat

A typical mass combat encounter is a clash between two sides, typically armies, that employ militia, special units, mounted combatants, archers, siege weapons, and heroes. The game organizes the chaos of mass combat into a cycle of rounds and turns.

A round represents about 6 seconds in the game world. During a round, each hero in a battle takes a turn. Non-hero individual creatures and units do not take their own turns, but instead, move and take actions when commanded to by heroes, or as part of the Clean-Up phase.

The order of turns is determined at the beginning of a combat encounter when all heroes (characters and opposing combatants) roll initiative. Once everyone has taken a turn, there is a Clean-Up phase, and then the fight continues to the next round if neither side has defeated the other.

Surprise

The GM determines who might be surprised. If neither side tries to be stealthy with any of its units or heroes, they automatically notice each other. Otherwise, the GM compares the Dexterity (Stealth) check of any hero or unit hiding with the passive Wisdom (Perception) score of the opposing side. Any unit or hero that doesn’t notice a threat is surprised at the start of the combat. If a hero notices a threat, it can alert a number of units within 30 feet of it equal to its Charisma modifier proficiency bonus.

If a unit or a hero is surprised, it can’t move or take an action on its first turn of the combat, and it can’t take a reaction until that turn ends.

Mass Combat Initiative

Initiative determines the order of heroes during combat. When combat starts, every hero makes an Intelligence check to determine their place in the initiative order. The GM makes rolls for each of the opposing side’s heroes as well. Units and non-hero individual creatures do not roll initiative.

The GM ranks the heroes in order from the one with the highest Intelligence check total to the one with the lowest. This is the order (called the mass combat initiative order) in which they act during each round. The initiative order remains the same from round to round.

If a tie occurs, the GM decides the order among tied GM-controlled heroes (including NPCs supporting the characters), and the players decide the order among their tied characters. The GM decides the order if the tie is between one of the opposing side’s heroes and a player character. Optionally, the GM can have the tied characters and GM-controlled heroes each roll a d20 to determine the order, highest roll going first.

Your Turn

On your turn, you can move your hero a distance up to your speed and take one action. You decide whether to move first or take your action first. Your hero’s speed–sometimes called your walking speed–is noted on your character sheet.

The common actions your hero can take are described in the “Actions in Mass Combat’ section later in this chapter. Many class features and other abilities provide additional options for your hero’s action.

The “Movement and Position” section later in this article gives the rules for your hero’s move.

You can forgo moving, taking an action, or doing anything at all on your turn. If you can’t decide what to do on your turn, consider taking the Dodge or Ready action, as described in “Actions in Combat” section of chapter 9 of the PHB.

Bonus Actions

Bonus actions function the exact same way that they do in traditional Fifth Edition combat encounters, however, some effects may be limited by the mass combat rules.

Other Activity on Your Turn

Your turn can include a variety of flourishes that require neither your action nor your move. These extra flourishes are described in detail in the PHB.

Reactions

Reactions function the exact same way that they do in traditional Fifth Edition combat encounters, however, some effects may be limited by the mass combat rules.

Movement and Position

In mass combat, units and individual creatures are in constant motion, often using movement and position to gain the upper hand.

On your turn, you can move your hero a distance up to your speed. You can use as much or as little of your hero’s speed as you like on your turn, following the rules.

If you are part of a unit, you and the unit move as one up the unit’s speed even if your speed is less than the unit’s speed.

Any unit that you command using the Command action can also move a distance up to the unit’s speed.

Individual creature and unit movement can include jumping, climbing, and swimming. These different modes of movement can be combined with walking, or they can constitute the unit or individual creature’s entire move. However the unit or individual creature moves, it deducts the distance of each part of its move from the speed until it is used up or until it is done moving.

Breaking Up The Move

An individual creature or unit can break up movement during its move, using some of its speed before or after its action. For example, if a unit has a speed of 30 feet, it can move 10 feet, take its action, and then move 20 feet.

Moving Between Attacks

If a unit or individual creature takes an action that includes more than one weapon attack, it can break up its movement even further by moving between those attacks. For example, a unit of dwarves that can make two attacks with the Multiattack trait and has a speed of 25 feet could move 10 feet, make an attack, move 15 feet, and then attack again.

Using Different Speeds

If a unit or individual creature has more than one speed, such as a walking speed and a flying speed, it can switch back and forth between the speeds during its move. Whenever it switches, subtract the distance it’s already moved from the new speed. The result determines how much farther it can move. If the result is 0 or less, it can’t use the new speed during the current move.

For example, if a unit of griffon riders has a speed of 30 and a flying speed of 80, it could fly 20 feet, then walk 10 feet, and then leap into the air to fly 60 more feet.

Difficult Terrain

Difficult terrain can include overgrown gardens, uneven grounds, or sucking mud.

Every foot of movement in difficult terrain costs 1 extra foot. This rule is true even if multiple things in a space count as difficult terrain.

Low furniture, rubble, undergrowth, steep stairs, snow, and shallow bogs are examples of difficult terrain. The space of another creature, whether hostile or not, also counts as difficult terrain.

Being Prone

Combatants often find themselves lying on the ground, either because they are knocked down or because they throw themselves down. In the game, they are prone.

An individual creature or unit can drop prone without using any of its speed. Standing up takes more effort; doing so costs an amount of movement equal to half the creature or unit’s speed. For example, if a unit of ogres’ speed is 30 feet, it must spend 15 feet of movement to stand up. A creature or unit can’t stand up if it doesn’t have enough movement left or if its speed is 0.

To move while prone, an individual creature or unit must crawl or use magic such as teleportation. Every foot of movement while crawling costs 1 extra foot. Crawling 1 foot in difficult terrain, therefore, costs 3 feet of movement.

Moving Around Creatures and Units – Heroes

An individual creature can move through a nonhostile individual creature’s or unit’s space. An individual creature can move through a hostile creature’s space only if the creature is at least two sizes larger or smaller than the hostile creature. An individual creature can move through a hostile unit’s space, however, doing so provokes an attack of opportunity from the unit.

Remember that another creature’s or unit’s space is difficult terrain.

If a hero enters the same space as a nonhostile unit, it can choose to join the unit as a free action. When a hero joins a unit, it can use the Command action to control the unit. The unit a hero is a part of does not count towards the number of units the hero is normally able to command.

Move Around Creatures and Units – Units

A unit can move through a nonhostile individual creature’s or unit’s space. A unit can move through a hostile individual creature’s or unit’s space if the creature or unit is at least one size smaller than the unit.

A unit cannot willingly end its move in a another unit’s space.

If a unit enters the same space as a nonhostile hero and ends its turn sharing the hero’s space, the hero can willingly join the unit at the start of its turn.

A unit can use the Attack action to make an attack against a creature that it shares the same space with as either a part of a command or during the Orders step of the Clean-up phase.

Flying Movement

Flying creatures and units enjoy many benefits of mobility, but they must also deal with the danger of falling. If a flying creature or unit is knocked prone, has its speed reduced to 0, or is otherwise deprived of the ability to move, the creature or unit falls unless it has the ability to hover or it is being held aloft by magic, such as by the fly spell.

Creature Size

Each individual creature and unit takes up a different amount of space. The Size Categories table in chapter 9 of the PHB shows how much space a creature of a particular size controls in combat. Objects sometimes use the same size categories.

Space

An individual creature’s or unit’s space is the area in feet that it effectively controls in combat, not an expression of its physical dimensions. A typical Medium creature isn’t 5 feet wide, for example, but it does control a space that wide. If a Large ogre stands in a 10-foot wide doorway, other creatures can’t get through unless the ogre lets them.

An individual creature’s or unit’s space also reflects the area it needs to fight effectively. For that reason, there is a limit to the number of creatures or units that can surround another creature or unit in combat. Assuming Medium combatants, eight creatures can fit in a 5-foot radius around another one. Because larger creatures take up more space, fewer of them can surround a creature. If five Large creatures crowd around a Medium or smaller one, there’s little room for anyone else. In contrast, as many as twenty Medium heroes or units can surround a Gargantuan hero or unit.

Squeezing Into a Smaller Space

An individual creature or unit can squeeze through a space that is large enough for a creature one size smaller than it. Thus, a Large creature or unit can squeeze through a passage that’s only 5 feet wide. While squeezing through a space, a creature or unit must spend 1 extra foot for every foot it moves there, and it has disadvantage on attack rolls and Dexterity saving throws. Attack rolls against the creature or unit have advantage while it’s in the smaller space.

Hero Actions in Mass Combat

When you take your action on your turn, you can take one of the actions presented in the PHB, one of the actions presented here, an action you gained from your class or a special feature, or an action that you improvised.

When you describe an action not detailed elsewhere in the rules, the GM tells you whether that action is possible and what kind of roll you need to make, if any, to determine success or failure.

The actions normally available to a character in the PHB are available to a hero during mass combat. However, there are two additional action options available to heroes while in mass combat: Challenge and Command.

Challenge

You can target one unit within 5 feet of you that you can see. You must then make a Charisma (Intimidation) check contested by the unit leader’s Wisdom (Insight) check. If you are successful, you may enter the target unit without provoking an attack of opportunity. While within the target unit, you cannot be targeted by the unit’s attacks and the unit cannot move or take actions. You may then fight the target unit’s leader (either an enemy hero that is present within the target unit or an individual unit using the base creature’s normal stats). If you defeat the unit’s leader, the unit automatically becomes broken (see “Morale Saving Throws” below). If you leave the unit, the unit can move and take actions again as normal

Command

You can command a number of units within 30 feet of you equal to your Charisma modifier (minimum of one) proficiency bonus. In addition, you automatically Command any unit that you are a part of. You cannot command any unit that already has an Activated token on it, or is incapacitated.

While under your command, the unit takes its turn during your turn. The unit moves to where you want it to using the normal movement rules, and it can take the Attack, Dash, Defend, Guard, Hide, or Rally unit action.

You can only use the Rally action on broken units. See details in the “Morale Saving Throws” section of this article.

After you command a unit, place an Activated token on the unit to signify that it cannot be commanded again until the next round.

 

Unit Actions in Mass Combat

A unit can only take actions in a round if it is commanded by a hero. A unit not commanded by a hero can only take reactions or follow any previously issued command such as Defend or Guard during the Orders step of the Clean-Up Phase. When Commanded, the unit can take one of the actions presented here, or an action that the hero improvises. Many monster units have action options of their own in their stat blocks.

Attack

The most common action a unit takes in combat is the Attack action. With this action, the unit makes one melee or ranged attack. See the “Making an Attack” section for the rules that govern attacks.

Certain features, such as Multiattack, allow the unit to make more than one attack with this action.

Dash

When the unit takes the Dash action, it gains extra movement for the current turn. The increase equals the unit’s speed, after applying any modifiers. With a speed of 30 feet, for example, the unit can move up to 60 feet on its turn if it dashes.

Any increase or decreases to the unit’s speed changes this additional movement by the same amount. If the unit’s speed of 30 feet is reduced to 15 feet, for instance, the unit can move up to 30 feet this turn if it dashes.

Defend

When a unit takes the Defend action, it focuses entirely on avoiding attacks. Place a Defend token on the unit. Until the unit is commanded again, any attack roll made against the unit has disadvantage as long as the unit can see the attacker, and it makes Dexterity saving throws with advantage. The unit loses this benefit if it is incapacitated or its speed drops to 0. While defending, the unit does not make attacks during the Clean-Up phase during the Orders step. If the unit is commanded to perform a different action on a subsequent round, remove its Defend token.

Guard

When a unit takes the Guard action, it focuses entirely on attacking enemies that come within range of it. Until the unit is commanded again, it makes an attack against the nearest enemy unit within its reach or range during the Orders step of the Clean-up Phase. Unless a unit is incapacitated, broken, or defending, it is automatically considered to have taken the Guard command.

Hide

When a unit takes the Hide action, it makes a Dexterity (Stealth) check in an attempt to hide, following the rules in chapter 7 of the PHB for hiding. If successful, the unit gains certain benefits, as described in the “Unseen Attackers and Targets” section later in this chapter.

Rally

When a unit is commanded to rally, before it moves, the unit must make a Morale saving throw and adds your Charisma modifier to the roll. On a failure, the broken unit must use its full movement to move towards the edge of the battlefield. On a success, you can move the unit to where you want.

Attacks by Creatures

The rules for creatures making attacks against other creatures is the same as detailed in chapter 9 of the PHB. However, the rules for a creature making an attack against a unit have a few modifications as detailed below.

Targeting a Unit

A creatire cannot target a unit with an attack that targets only one creature or target such as a melee weapon attack or ranged weapon attack. However, if the creature has a spell or other effect that targets an Area of Effect, it can target the unit with the following restrictions:

  • If the attack’s area covers 100% of the unit as well as each space within 5 feet of the unit, completely enveloping it, the creature makes its attack roll against the unit with advantage or the unit makes its normal saving throw against the attack with disadvantage. For example, if a wizard targets a unit with a fireball spell and the fireball completely covers the unit as well as everything within 5 feet of the unit, the unit makes its Dexterity saving throw at disadvantage.
  • If the attack’s area covers 100% of the unit, the creature makes its normal attack roll against the unit or the unit makes its normal saving throw against the attack. For example, if a cleric uses the thunderwave spell on a unit and the area of the spell covers 100% of the unit, the unit must make its normal Constitution saving throw to avoid the spell’s effects.
  • If the attack’s area covers less than 100% of the unit, but at least 50% or more, the creature makes its attack roll against the unit with disadvantage or the unit makes its saving throw against the attack with advantage. For example, if a sorcerer uses the burning hands spell and only hits 75% of a unit, the unit makes its Dexterity saving throw with advantage.
  • If the attack’s area covers less than 50% of the unit, the attack has no effect.

A hero can use the Challenge action to target the unit’s commander as described in the “Heroes Actions in Mass Combat” section.

Individual Creature Attack Rolls Against Units

If a creature can attack the unit with an attack that requires an attack roll, it rolls a d20 adding the appropriate modifiers as normal. If the total of the attack roll plus modifiers equals or exceeds the unit’s Armor Class (AC), the attack hits.

Opportunity Attacks Against Units

Hostile units do not provoke attacks of opportunity from enemy units or creatures.

Grappling and Shoving Units

A unit cannot be grappled or shoved unless done so by a spell or similar effect that would affect the entire unit such as a web spell.

Optional Rule: Huge and Gargantuan Individual Creatures

Huge and Gargantuan creatures are large enough to deal damage to multiple targets at once. A Huge or Gargantuan creature receives a new Action that allows one of its normal melee attacks to target a unit that is at least one size or smaller than it. On a hit, the creature deals unit damage equal to its attack’s average damage divided by 8 (rounded down). For example, an Ancient Black Dragon can make a bite attack targeting a unit. On a hit, it deals 2 unit damage to the unit or half as much damage on a miss.

 

Attacks by Units

A unit makes attacks similar to how a hero makes attacks:

  1. The unit chooses a target. Pick a target within the unit’s attack range: a creature, an object, or a location.
  2. Determine modifier. The GM determines whether the target has cover and whether the unit has advantage or disadvantage against the target. In additional, spells, special abilities, and other effects can apply penalties or bonuses to the attack roll.
  3. Resolve the attack. The unit makes the attack roll. On a hit, the unit rolls damage, unless the particular attack has rules that specify otherwise. Some attacks cause special effects in addition to or instead of damage.

If there’s ever any question whether something the unit is doing counts as an attack, the rule is simple: if you’re making an attack roll, you’re making an attack.

Attack Rolls

Units make attack rolls the same way that creatures make attack rolls as detailed in chapter 9 of the PHB. However, there are a few additional rules modifications:

Units Attack Individual Creature

When a unit attacks an individual creature that it one or more size categories smaller than it, it makes its attack roll with advantage.

If a unit makes a melee attack roll against an individual creature, the unit automatically hits if the attack roll it would need to hit the creature is an 18 or less and the unit does not have disadvantage on its attack roll.

Grappling, Shoving, and Seizing

A unit cannot grapple or shove another unit. However, a unit can attempt to seize a target. The target of the unit’s grapple must be no more than one size larger than it and must be within its reach. The unit tries to seize the target by making a grapple check instead of an attack roll: a Strength (Athletics) check made with advantage contested by the target’s Strength (Athletics) or Dexterity (Acrobatics) check (the target chooses the ability to use. If the unit succeeds, the target is subjected to the grappled condition. The condition specifies the things that end it, and a unit can release the target whenever it likes (no reaction required).

Escaping a Seizure. A seized creature can use its action to escape. To do so, it must succeed on a Strength (Athletics) or Dexterity (Acrobatics) check contested by the unit’s Strength (Athletics) check made with advantage.

Moving a Seized Creature. When the unit moves, it can drag or carry the grappled creature with it at its normal speed. If the creature is one or more sizes bigger than the unit, the unit’s speed is halved.

 

Cover

Cover functions the same way for units and individual creatures that it does according to the rules in chapter 9 of the PHB.

 

Damage and Healing in Mass Combat

For individual creatures in mass combat, damage and healing function the same way they normally do. Refer to chapter 9 of the PHB for details.

However, there are a few rules modifications for units.

Unit Hit Points

A unit’s unit hit points are the combination of the physical and mental durability, the will to live, and luck of the entire unit as a whole. Unit hit points are a simplified way of tracking hit points for large groups.

The unit’s unit hit points are usually the total hit points of a unit divided by 40 (rounded down, a minimum of one). For example, where an individual knight would have 52 hit points, a unit of eight knights has 416 hit points, or 10 unit hit points.

Whenever the unit takes unit damage, that unit damage is subtracted from its unit hit points. If the unit’s unit hit points drop to half or less of its total unit hit points, the unit has disadvantage on its attack rolls, ability checks, and saving throws.

Unit Damage

Units deal a lot more damage with successful hits than individual creatures do. When attacking another unit, that damage is represented by unit damage. Unit damage is usually the average amount of damage each member of the unit would do combined divided by 40 (round down, minimum of one). For example, an individual knight would normally deal 10 slashing damage with its greatsword, but a unit of eight knights would deal 80 slashing damage with their greatswords, or 2 slashing unit damage.

In addition, when a unit misses and it did not have disadvantage on its attack roll, it deals half its normal unit damage (rounded down). If rounding the damage down would reduce the unit’s unit damage to zero, it deals 0 unit damage. For example, if a unit of knights misses with its attack and it didn’t have disadvantage, it still deals 1 unit damage.

Units Damage Against Individual Creatures

When a unit hits with an attack against an individual creature, it deals an amount of damage equal to its unit damage times 20. For example, if a unit of knights attacks a single ogre and hits it, the unit deals 40 unit damage to the ogre.

If the unit misses on its attack roll against an individual creature and it didn’t have disadvantage on the roll, it still deals an amount of damage equal to its unit damage times 10.

Individual Creature Damage Against Units

If an individual creature hits a unit with an attack that can target it such as a spell with an area of effect, the damage the unit receives is equal to the damage rolled divided by 5  (rounded down). For example, a wizard lobs a fireball at a unit of knights and the knights fail their Dexterity saving throw. The wizard rolls 27 fire damage; that means the unit of knights takes 5 fire unit damage from the attack (27/5 = 5)

Unit Critical Hits

Units do not receive the benefit of extra damage on a critical hit.

Advantage on Unit Attack Rolls

When a unit makes an attack roll with advantage and hits, it deals double its normal unit damage to the target. And if a unit makes an attack roll with advantage and misses, it deals its normal unit damage.

Disadvantage on Unit Attack Rolls

When a unit makes an attack roll with disadvantage and hits, it only deals half of its normal unit damage to the target. And if a unit makes an attack roll with disadvantage and misses, it deals 0 unit damage regardless of what its unit damage is.

Units with Damage Resistance and Vulnerability

If a unit has resistance to a damage type, the damage of that type is halved against it (rounded down). If rounding down would reduce the damage to zero, the unit takes 0 unit damage from the attack. If a unit has vulnerability to the damage type, damage of that type is doubled against it.

Resistance and then vulnerability are applied after all other modifiers to damage. Multiple instances of resistance or vulnerability that affect the same damage type count as only one instance.

Healing Units

Units can only be healed with a mass heal spell which can heal up to 17 unit hit points for units within range.

Dropping to 0 Unit Hit Points

When a unit drops to 0 unit hit points, it is destroyed.

Unit Attacks Against Incapacitated Units or Creatures

If a unit or creature is incapacitated, it is vulnerable to attacks from enemy units. If an enemy unit makes an attack against an entire unit that is incapacitated, the unit is instantly destroyed. If an enemy unit makes an attack against an individual creature that is incapacitated, the creature instantly dies as if it had failed all of its death saving throws.

Units Knocking a Creature Out

A unit can incapacitate an individual creature instead of killing it. When a unit reduces a creature to 0 hit points with a melee attack, the attacking unit can knock the creature out. The attacker can make this choice the instant the damage is dealt. The creature falls unconscious and is stable.

Temporary Hit Points for Units

Units cannot receive temporary hit points.

Mounted Combat for Units

As long as at least eight mounts are available within reach of a unit, a unit can mount the creatures.

Eight willing creatures that are at least one size category larger than the unit (but no larger than Large) can serve as mounts for the unit using the following rules.

Mounting and Dismounting

Once during the unit’s move, it can mount eight creatures that are within 5 feet of it or dismount. Doing so costs an amount of movement equal to half the unit’s speed. For example, if the unit’s speed is 30 feet, it must spend 15 feet of movement to mount horses. Therefore, a unit can’t mount if it doesn’t have 15 feet of movement left or if its speed is 0.

If an effect moves the mount against its will while the unit’s on it, the unit must succeed on a DC 10 Dexterity saving throw or fall off its mounts, landing prone in a space within 5 feet of its mounts. If the unit’s knocked prone while mounted, it must make the same saving throw.

If the mounts are knocked prone, the unit can use its reaction to dismount it as it falls and land on its feet. Otherwise, the unit is dismounted and falls prone in a space within 5 feet of its mounts.

Benefits of Mounting

Unlike mounted heroes, the units and mounts act as one. The unit gains the following benefits while mounted:

  • The unit’s size increases according to the size of the unit it is on as follows:
    • Units mounted on Large creatures become a Gargantuan unit.
    • Units mounted on Small or Medium creatures become a Large unit
  • The unit’s unit hit points increases by an amount equal to the mount’s average hit points divided by 5. For example, if a unit of knights mounts riding horses, the knight’s unit hit points increases by 2 to 12.
  • The unit’s speed equals the mounts’ speed.
  • If the mounts have any special traits related to movement or defense, the unit gains those traits.

Units in Underwater Combat

Units are affected by being underwater the same as individual creatures as detailed in chapter 9 of the PHB.

Siege Weapons in Mass Combat

The rules for siege weapons are a little different than the ones outlined in chapter 8 of the DMG.

Siege Weapon Stats

The siege weapon’s stats are different while in mass combat. The siege weapons outlined in chapter 8 of the DMG have the following updates:

Ballistas. The ballista is considered an individual creature. Instead of its normal attack, a ballista fires a bolt in 120-foot line that is 5-feet wide. Each individual creature in the line must make a DC 14 Dexterity saving throw or take 16 (3d10) piercing damage. If the line hits at least 50% of a unit, the unit must make a DC 14 Dexterity saving throw or take 1 unit damage.

Cannon. The cannon is considered an individual creature. Instead of its normal attack, a cannon fires a cannonball in a 600-foot line that is 5 feet wide. Each individual creature in the line must make a DC 14 Dexterity saving throw or take 44 (8d10) bludgeoning damage.

Suspended Cauldron. A suspended cauldron is considered an individual creature. When it uses its boiling attack against a unit, the unit must make a DC 15 Dexterity saving throw or take 2 unit damage on a failed saving throw or half as much damage on a successful one. Gargantuan units have advantage on the saving throw and take no damage with a successful save.

Mangonel. A mangonel is considered an individual creature. If the mangonel hits a unit with its mangonel stone, the unit takes 5 unit damage. If the mangonel misses a creature or a unit with its mangonel stone, the stone lands somewhere off course. See “Missed Artillery” below. A mangonel can make attacks against targets behind total cover with disadvantage.

Ram. A ram must be carried by a Large or larger unit. While carrying the ram, the unit has total cover against attacks from above. If a unit carrying a ram hits an object, it receives a +1 bonus to its unit damage if it is a Large unit or +4 bonus to its unit damage if it is a Gargantuan unit.

Trebuchet. A trebuchet is considered an individual creature. If the trebuchet hits a unit with its trebuchet stone, the unit takes 8 unit damage. If the trebuchet misses a creature or a unit with its trebuchet stone, the stone lands somewhere off course. See “Missed Artillery” below. A trebuchet can make attacks against targets behind total cover with disadvantage.

miss-chart

Missed Artillery

If a mangonel or trebuchet misses its target with one of its stones, there is still a chance that the stone deals damage. Roll a d8 and a d6 at the same time. The d8 determines the direction the stone flies; refer to the directional chart to the right. Next, multiply the d6 result by 10, and that is the number of feet away from the target the stone lands. For example, if you roll a 7 on the d8 and a 5 on the d6, the stone lands 50 feet to the southeast of the target.

If there is a creature, unit, or object in the space that the stone lands, it automatically takes damage as if the siege weapon successfully hit it with its attack roll.

Unit Morale Saving Throw

Special circumstances may require a unit to make a Morale saving throw. A unit’s Morale saving throw modifier equals its current unit hit points + its Wisdom modifier + the Charisma modifier of a hero within 30 feet of the unit.

Circumstances for Morale Saving Throws

The following are situations that can occur during mass combat that can cause a unit to make a Morale Saving throw.

Half Unit Hit Points or Less

Whenever a unit’s unit hit points drops to 50% or less its total, during the Clean-Up phrase, the unit must make a Morale saving throw to avoid becoming Broken.

If a unit rolls 10 or higher on its Morale saving throw, it becomes Hardened. Place a Hardened token on the unit’s token.

If a unit rolls 9 or lower, it becomes Broken. Place a Broken token on the unit. During the Orders step of the Clean-Up phase, a broken unit spends its turn moving as close to the nearest edge of the battlefield as it can. It also can’t take reactions. For its action, it can use only the Dash action or try to escape from an effect that prevents it from moving. If there’s nowhere to move, the unit can use the Defend action.

Overrunning. If a hostile unit attacks a broken unit, the broken unit is automatically destroyed by the attackers.

Rally. A hero can use the Command action to Rally a broken unit. The broken unit makes a new Morale saving throw adding the commanding hero’s Charisma bonus to its Morale saving throw modifier. If the unit succeeds on its saving throw, the unit gets a Hardened token and the hero can direct the unit to move up to its full speed where it wants. If the unit fails its saving throw, it continues to move towards the nearest edge of the battlefield.

Attacking Larger Units and Creatures

If the unit is commanded to move adjacent to a unit or creature that is one or more size categories larger than it, the unit must make a Morale saving throw. On a failed saving throw, the unit cannot move towards the unit.

Hardened Units

A unit with the Hardened token automatically passes all of its Morale saving throws until the end of the mass combat encounter.

The Clean-Up Phase

After all heroes have taken their turns, there is a Clean-Up phase that occurs before the next round begins.

The Clean-Up Phrase is divided into the following steps:

  1. Orders. All units without an Activation, Broken, or Defense token that aren’t incapacitated can make one attack against the nearest hostile unit or creature within its reach or range. The unit can only make one attack even if it has the Multiattack action. Broken units move as detailed in the “Broken Units” section.
  2. Morale. All units without a Hardened token that aren’t incapacitated that have 50% or less unit damage points must make Morale saving throws against becoming broken.
  3. Effects. Any lingering effects such as gases, fires, or spells such as darkness are adjusted or removed.
  4. Deactivate. All Activation tokens are removed from units.

 

Unit Stats Coming to Patreon

Okay, phew! That was a whole lot of writing. But sometimes, I just gotta get something out on paper. These rules have already been playtested by me, but be sure to test them out yourself and see what you think.

If you’d like a quick reference to units, I’ll be posting units on Patreon and in a finalized version of these rules in PDF format (probably sometime this week). Otherwise, you’ll have to create your own using the template above.

Become a Patron to get unit stats and additional combat options!

Have fun and see you soon!

Art by Wizards of the Coast and Simon Goinard.

4 thoughts on “Improved Mass Combat Rules (Part 2: Basic Rules) | Rules Supplement for Dungeons & Dragons Fifth Edition

  1. Thanks for this awesome article! It seems a lot easier than the UA article(which I wasn’t so much a fan of) one question though, so using this system you can’t mix and match creatures in a unit? like 3 guards and 5 thugs in a unit?

    1. If you look at it from an abstract, it’s all just numbers you’re fighting anyways. So those numbers can be anything you need them to be 😄

  2. Hi, I am a bit confused about units and initiative. Up in the section, “Mass Combat Unit Template” where it has the sub bullet titled “Initiative” it say that units have their own initiative score. But in the section, “The Order of Combat” it says units don’t have their own initiative. Which is which?

    1. Nola: hey, it’s a typo. In the original version, they had their own initiative, but I realized that would make things a mess. Thanks for pointing that out!

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