Drafting mass combat rules; open to suggestions

[Ronnocius]

I have written some extremely work-in-progress mass combat rules for my 5th edition game. I will probably not need a perfectly refined system, but I was unhappy with the Unearthed Arcana rules (although it has been a while since I have read them so perhaps I will have a different opinion now). Any input is appreciated. I have play tested it with two of the players (one of whom plays tabletop wargames) and they generally said it was alright to use in the game itself (and I would modify it based on problems that were discovered).

Mass Combat Rules
Each soldier in unit = 1 hit point.
Attack
Use soldier's attack bonus against Armor Class of defender. The damage is rolled on a die equal to how many soldiers are in the unit. Example = 30 soldiers in unit, d30 etc
Attacking units take losses equal to the amount of damage they did to a unit divided by 3 and rounded down.
Flanking
If a friendly unit is adjacent to the target unit, the attack has advantage.
Disengage
Once a unit is engaged in a melee with another unit, they cannot move unless they take the Disengage action.
Fortify
Fortifying gives a +1 bonus to AC from melee and +3 bonus to AC from ranged. Units who attack this unit take casualties equal to half of the damage they inflict, rounded down.
Rout
Once a unit is reduced to half of its starting number of soldiers they must succeed on a DC 10 morale check or they will break and rout, fleeing away from the battle. Melee units attacking routing units do not take casualties.
Special Action: Rally
Once per combat the commander can rally his troops, giving all attacks in the subsequent round advantage and any routed units stop fleeing.
Morale
Morale starts off at a default value of +4. Once half of the units in an army have either been destroyed or fled the battlefield the morale value decreases by 2. Other factors will influence morale as well.
Ranged
Ranged units have a range equal to the range of their ranged attack. Otherwise the rules are the same, but ranged units do not benefit from flanking.
Friendly Fire
If a friendly unit is adjacent to the target of a ranged unit attack they take half casualties regardless of whether attack was a hit or a miss.


They are quite unorganized so please ask for any clarification on what I meant. I have not made any rules for more complicated things (cavalry, siege etc). The main thing I am unhappy with is the damage, so I am open to alternative ways to determine how much damage a unit does (while still having it do less damage when it has lost soldiers).

EDIT: I completely forgot but apparently I have already posted a very similar thread asking for help, apologies. Any further suggestions are still welcome as that thread didn't receive much attention.

[Slayn82]

I think mass combat rules where unit = HP don't scale very well for a combat involving fantasy monsters. They seem to be designed with very equal forces in mind. But how will it work when you face a bunch of Ogres? When a Dragon attacks? When a wizard drops a fireball in their middle?

The actions seem to be fine.

Armies organize themselves on units, batallions and regiments. It's quality depends of what troops and gear you can muster.

On a limited time window, a melee engagement only happens between troops on the frontlines, for units that fight on formations, or becomes a braw if two units entangle. An unit that keeps good formation limits somewhat the enemy attacks, but they may be flanked. A unit that manages to force an entangle can't be flanked effectively, and makes it most dificult to the enemy to use area of effect attacks, but they lose several tactical advantages, like moving efficiently, retreating, shuffling damaged units behind safe lines while still helping/supporting fire.

[Ronnocius]

I think mass combat rules where unit = HP don't scale very well for a combat involving fantasy monsters. They seem to be designed with very equal forces in mind. But how will it work when you face a bunch of Ogres? When a Dragon attacks? When a wizard drops a fireball in their middle?

The actions seem to be fine.

Armies organize themselves on units, batallions and regiments. It's quality depends of what troops and gear you can muster.

On a limited time window, a melee engagement only happens between troops on the frontlines, for units that fight on formations, or becomes a braw if two units entangle. An unit that keeps good formation limits somewhat the enemy attacks, but they may be flanked. A unit that manages to force an entangle can't be flanked effectively, and makes it most dificult to the enemy to use area of effect attacks, but they lose several tactical advantages, like moving efficiently, retreating, shuffling damaged units behind safe lines while still helping/supporting fire.

Yeah those situations are not accounted for in my rules. I am hoping I would be able to adjudicate how large monsters would work on the fly. For 'elite' units such as ogres and knights I was thinking of giving them much increased hit points and they would inflict twice as much damage as a normal unit. Using the current damage system that means a wedge of 12 knights would be worth 48-96 hit points
(4-8 hit points per knight) and would do 2d12 damage. Not sure if this would be effective for elites however.

Also, what are some basic formations (because I think that would be quite interesting) and what would their effect be? You mention a possibility to 'entangle' in which you cannot be flanked. I am thinking this would mean you move into the same space that is being occupied by the enemy? What would be some downsides to entangling? (I am possibly thinking that troops simply cannot withdraw unless they rout or defeat the enemy unit?)

Thanks for the advice.

[Sudsboy]

We are playing a war in our campaign with the Unearthed Arcana rules, and they are working fairly well. It's particularly nice to have a system that smoothly transitions between mass combat and traditional D&D combat rounds.

We used to use DBM, as we have a very politics-heavy campaign, and wars happen all the time. It was OK, but the mechanics didn't jibe well with D&D.

[Ronnocius]

We are playing a war in our campaign with the Unearthed Arcana rules, and they are working fairly well. It's particularly nice to have a system that smoothly transitions between mass combat and traditional D&D combat rounds.

We used to use DBM, as we have a very politics-heavy campaign, and wars happen all the time. It was OK, but the mechanics didn't jibe well with D&D.

Are you using the newer set of Unearthed Arcana rules or the previous ones (I believe two have been released)? Also, what is DBM?

[Sudsboy]

Are you using the newer set of Unearthed Arcana rules or the previous ones (I believe two have been released)? Also, what is DBM?

We're using the ones from Feb. 21. 2017. I assume those are the latest. DBM is https://en.wikipedia.org/wiki/De_Bellis_Multitudinis

[Calimehter]

There was a DnD 3.5 Miniatures Handbook that had some more in depth rules that might be worth checking out if you can get a copy. They not only have the 'basic soldier' system in but they also account for monsters, spells, etc.. They seemed very Warhammer inspired to me when I looked them over, but I didn't experiment too much with them, and the might need a bit of work to import into 5e. Even if you don't use them straight up, it might be a good source for mining ideas.

[Laserlight]

In the OP, "units adjacent to the attacking unit provide Advantage" is much too powerful. Maybe a +1 or possibly +2 for having an unopposed adjacent unit, but not more. If a target is pinned in front and a unit swings around to attack its flank, that flank attack could have advantage.

The "units adjacent to the target take half damage" is an invitation to bring lots of cheap, inaccurate, high damage archers and let them accidentally wipe out the enemy in a burst of cheese.

[Ronnocius]

In the OP, "units adjacent to the attacking unit provide Advantage" is much too powerful. Maybe a +1 or possibly +2 for having an unopposed adjacent unit, but not more. If a target is pinned in front and a unit swings around to attack its flank, that flank attack could have advantage.

The "units adjacent to the target take half damage" is an invitation to bring lots of cheap, inaccurate, high damage archers and let them accidentally wipe out the enemy in a burst of cheese.

I usually granted flanking advantage only if there was the target unit was engaged in melee with two units on two fronts. My friend who plays wargames also suggested that flanking should be nerfed. My reasoning behind having flanking be powerful is so that if one flank of the enemy collapses (say the right flank) then the units on your right flank can swing to the centre and support your forces there even if depleted by giving advantage. In terms of the "units adjacent to the target take half damage", if this is referring to friendly fire that would only affect adjacent friendly units (meant to make archers become useless once the armies collide except for taking out routing units) although I realize that doesn't make much sense.

[Ronnocius]

Here are some formations I have thought of, are these over powered? Any ideas for other formations, or adjustments to the existing ones?

Shield Wall
The unit must have shields. The unit forms a shieldwall as an action. Its speed is halved while in this formation. This unit receives a defensive bonus from the direction it is facing. Any melee attacks from this direction have disadvantage. However, any attacks from other directions have advantage. The unit gets three quarters cover from ranged attacks from the direction it is facing. Reorganizing from this formation requires an action.

Spear Wall
This unit must have spears or other applicable polearms. The unit forms a spearwall as an action. Its speed is zero while in this formation. This unit receives a defensive bonus from the direction it is facing. Any cavalry charges from this direction have disadvantage, and the attacking unit takes damage equal to twice as many hit points as they remove (if the attack is a miss, they roll damage and take twice as much anyways). Melee attacks from any other direction have advantage. If you attack the formation is immediately broken. Reorganizing from this formation requires an action.

Schiltrom
This unit forms a defensive square and faces all directions as an action. Its speed is zero while in this formation. Units who attack the schiltrom do not benefit from flanking. If you attack the formation is immediately broken. Reorganizing from this formation requires an action.

[Man_Over_Game]

On the basic rules, I really like what you've put into it, but I don't necessarily agree with how your attack/damage formula is. Notably, a d30 is a pretty hard thing to find some of the time. Possible with a computer maybe, but I think there might be a more elegant solution.

Damage/hit/= XD8 + 2*CR.

AC =10 + X + 2*CR



Where X is every 10 attacking troops.

This is pretty elegant and balanced for use with players. 30 CR1 units have 3d8 + 2 to hit (average 15.5) and have an AC of 15. Damage is dealt to all targets within the hex who's AC was within the hit range.

-----------


Additionally, consider adding a mechanic called Morale, which acts as temporary HP for troops. Morale can be provided by a good general (who provides +4 morale every turn, non-stacking), an allied hero within the unit acting as a commander (Proficiency as morale each turn), or it can also act as a penalty (a player assassinated an enemy captain, enemy team loses 3 HP per turn, starting with Morale).

With Morale, you can comfortably shift around the numbers without increasing/decreasing a unit's power level, while also allowing players to directly affect the battlefield conditions in an easily recognizable way. Maybe have certain special actions influence morale, such as a Commander's Charge (An ally makes a melee weapon attack roll. If you move adjacent to an enemy hex and attack it, add the hero's attack roll to the unit's morale. Lose this much morale/HP at the start of the unit's next turn).