How to do a Mass Battle?

[Cheesegear]

Not sure if this should go into the homebrew part or here. So mods can move it if they want.

How would one go about doing well...Large-scale battles? The only one I can think of in official terms, is the one at the end of Rise of Tiamat, and, spoiler alert, if you actually know that module, that's not what happens. Much to every single one of my players' annoyance. :smallmad:

I want multiple creatures of multiple types fighting other multiple creatures of multiple types...And I want the players to be involved. But I also want the dice to actually play a part in the battle so chance and randomness is actually involved, and the outcome of the battle isn't just pre-determined by me...But I don't know how to do that in any...Sane...Way.

[tokek]

Strangely enough I have never run this in D&D but I have in a couple of other fantasy games and the principles remain the same.

Narratively find a key thing that can turn the battle. That is where the party have to get to and that defines what they need to achieve.

So perhaps that is a key command group that is directing the enemy forces, or a small number of powerful mages whose magic will devastate the friendly forces or tear down fortress walls. Let your imagination run free here - it could be some sort of magical shield that protects the enemy forces and if its destroyed the friendly mages can turn the battle. In all cases the objective is to make the turning point of the battle be something that a small elite force (a D&D party) could realistically deal with. You could have this be the need to take out the enemy commander if BBEG fights are your thing.

Now to get there you will need other encounters, some of which will be combat and some non-combat. The party probably has to navigate around the flanks of the main battle, evading some scouts and fighting others before they can get to where they need to be. Perimeter guards against flanking action will make for interesting mini-battles without needing to involve the thousands of creatures of the main battle. The backdrop to this is the noise of the battle, that is what gives it all urgency. The ability to take short rests is keyed to the pace of that main battle, if it is relentless then the pace of the party must be relentless - but sieges were rarely that relentless and I always recommend making room for a short rest in D&D.

Unless the enemy are undead or similar they will probably crumble and fall into retreat when this key objective is achieved, whatever it is. Sentient armies rarely fight on if its hopeless. If they are undead then the key objective is probably whatever allows the control of a whole army of undead - the loss of which would leave them as a milling uncoordinated mass which is much less challenging for an army to deal with.

The outcome is not pre-determined, its determined by the actions of the players.

[Sillybird99]

There are homebrew and 3rd party options for this, but a simple way would be to use a single creature to represent a large unit of creatures, or even convert a single creature into a swarm. So you. You have a unit (or swarm) of skeleton archers, the archers roll to attack the unit (or Swarm) of kobolds. Idk if that is the kinda thing you are looking for, but without adding a bunch of homebrew mechanics, that is how I would do it.

[Pildion]

Not sure if this should go into the homebrew part or here. So mods can move it if they want.

How would one go about doing well...Large-scale battles? The only one I can think of in official terms, is the one at the end of Rise of Tiamat, and, spoiler alert, if you actually know that module, that's not what happens. Much to every single one of my players' annoyance. :smallmad:

I want multiple creatures of multiple types fighting other multiple creatures of multiple types...And I want the players to be involved. But I also want the dice to actually play a part in the battle so chance and randomness is actually involved, and the outcome of the battle isn't just pre-determined by me...But I don't know how to do that in any...Sane...Way.

I would recommend using both swarms and the damage table. Create the swarms out of the different "fighting types" and have them use the damage table, so +hit with number of attacks on the attacking swarm vs target swarm AC. Otherwise it will take to long to really be viable.

[Unoriginal]

Not sure if this should go into the homebrew part or here. So mods can move it if they want.

How would one go about doing well...Large-scale battles? The only one I can think of in official terms, is the one at the end of Rise of Tiamat, and, spoiler alert, if you actually know that module, that's not what happens. Much to every single one of my players' annoyance. :smallmad:

I want multiple creatures of multiple types fighting other multiple creatures of multiple types...And I want the players to be involved. But I also want the dice to actually play a part in the battle so chance and randomness is actually involved, and the outcome of the battle isn't just pre-determined by me...But I don't know how to do that in any...Sane...Way.

Have you read the old Uneartherd Arcana on this subject? It may be enough for your needs/wants.

[Cheesegear]

The party probably has to navigate around the flanks of the main battle...

No they don't. They probably have to fight on the front lines, in the crush, where their Fireballs, and battle magic will deal the most damage, with the militia and the Knights, and people who can see them, and say 'He who bleeds with me this day shall be my brother...' When the Paladin lights up his sword, and plants a Banner, the peasants around him, gain courage, grip their spears tighter and plant their feet and Hold the Line. The Bard needs to Countercharm hard, etc.


What you're suggesting is the ending of Rise of Tiamat, which I already explained is what I don't want...A big massive battle of epic proportions...That the players don't participate in, and potentially might not even see as they run off to do...Something else. To be clear, I'm not saying that the 'something else' the players do in the module isn't important and epic in a different way... What I am saying is that the big massive battle at the end doesn't have a point (despite everything in the module leading up to it), because the players don't participate in it.


Unless the enemy are undead or similar they will probably crumble and fall into retreat when this key objective is achieved...

They are being mind-controlled by Asmodeus Himself. You fight or you're enslaved...Or you die. Or both. And not necessarily in that order.


or even convert a single creature into a swarm. You have a unit (or swarm) of skeleton archers, the archers roll to attack the unit (or Swarm) of kobolds.

This how I thought I would do it. But looking at the creatures that already exist; A rat, and a swarm of rats aren't even close to the same thing:
- A rat has 1 HP, a swarm has 24; So I guess maybe ~20 rats in a swarm? But where does the 2d6 damage dice come from?
- A rat has STR 2 (-4), a swarm has STR 9 (-1)...How did we get there? :smallconfused:

Making Swarms sounds like the most obvious thing to do...I just don't know what the template is to make one, because the current Swarms seem all over the place and confuse me when compared to their non-swarm equivalents. :smallsigh:


Have you read the old Uneartherd Arcana on this subject? It may be enough for your needs/wants.

I forgot that that existed.

I looked at it. There are a lot of new mechanics that I don't really want to bother learning, and I don't want to have to teach my players new mechanics, either, for probably something that I wont ever do again. I dunno. Feels like it's on the right track...But it's just not...Good?

[Sillybird99]

Yeah I don't think WoTC has a swarm template. I found a decent homebrew swarm template on reddit though. You could find something like that and adjust as needed.

[Kurt Kurageous]

There are no less than TWO attempts in UA to provide a rules supplement. The first, "When Armies Clash" (or something) might as well be its own wargame and is not something you can easily adapt. I so wanted it to work.

I never read the second one.

I have never had to resolve a battle, but if I did, I would rely on average hits/damage for the NPCs, and let the players do their own damage as they will.

I'd use tokens on a map where each square is a 30x30. You can target what's in the square if you can reach the center of the square. The map would have terrain that could slow movement (difficult), grant cover (disadvantage to ranged), grant bonuses to hit (high ground).

In short, KISS. It will be awful, but at least you have justifications for your outcomes.

Better yet, don't. My preferred approach is the Players get specific missions and aren't in the general brawl. I already know what it will take for victory/defeat as DM, and I put the players in a key spot where they get to be stars, not just cannons.

[Keravath]

A couple of comments ...

pg 250 of the DMG has brief rules for handling mobs of creatures reducing the number of die rolls though it is pretty crude it might work.

As for how you want to model a battle - that is more challenging. How common are adventurers in your world? Especially high level ones?

Your image is the following ...

"No they don't. They probably have to fight on the front lines, in the crush, where their Fireballs, and battle magic will deal the most damage, with the militia and the Knights, and people who can see them, and say 'He who bleeds with me this day shall be my brother...' When the Paladin lights up his sword, and plants a Banner, the peasants around him, gain courage, grip their spears tighter and plant their feet and Hold the Line. The Bard needs to Countercharm hard, etc."

However, unless there are a MASSIVE number of mages in your world, that isn't a decent description. It could apply to maybe an elite force of 100 or so opponents in a small area but in a battle of thousands it would be the crossbows and swords of the regular army and militia that make the difference.

Consider an army facing a few mages ... they bombard them with crossbows while their own mages try to make them vulnerable. Even a wizard isn't usually immune to flaming tar from a catapult hurled from several hundred feet away. The scale of spells in D&D is miniscule compared to the battlefield of thousands of soldiers. The specialized forces (like adventurers) play crucial roles tipping the trend of battle in various places but the front lines would not usually be "fireballs and battle magic" ... a fireball is likely far less effective than a catapult with flaming oil soaked rags, or an explosive material, or even grapeshot or rocks of various sizes that can be reloaded and fired all day as long as the ammunition holds out.

If you want the "fireball and battle magic" feel then you probably want the characters to have a specific assignment to take out opposing leadership (if possible) or some other strategic objective where defenses can be concentrated and they have to face the equivalent of other adventurers while the rest of the battle plays out on the sidelines.

The rules for handling mobs might work ok for the 100 or so creatures near the PCs - with some falling on either side every round or two while you set the tone with the fireballs and such from local defenders that the PCs have to take out to achieve their objective. (The problem is that if you just put the PCs at a random spot on the battlefield - most game worlds wouldn't have enough mages at any one location to be a challenge so the PCs have to slaughter large numbers of regular militia and such who are mind controlled). If the PCs do become a local challenge then the opposition will likely send special forces (read other adventurers or even devils in this case) off to eliminate the PCs. Possibly in waves, possibly getting stronger each time - though if the PCs succeed it could break the back of the opposing army.

However, you said the opponents are mind controlled and won't surrender. This likely means that the PCs allies are far more likely to break and run since their morale will fail at some point due to the unstoppable mob and they will run and hope to hide somewhere.

Anyway, best of luck :) ... it can be challenging to create a large scale set piece battle while trying to give the PCs a significant role in it.

[Slipjig]

If you want to simulate a clash of massive armies, D&D is simply not a good system to do it in. If you want to run massive battles, pick a system that's actually designed for it and convert your characters over. Unless your PCs are commanding the battle, there's no reason to roll dice for fights they aren't involved in.

But if they are commanding the battle and you want to simulate it, run the fight as normal with normal stats, but each combatant narratively standing in for a multiple of whatever the smaller side is in that particular confrontation.

So for a matchup between 100 orcs vs 200 peasants, run the fight as normal between 2 peasants and 1 orc. For a fight between 20 knights and 80 orcs, run it with 1 knight vs. 4 orcs. When a creature runs out of hp, everybody in that troops is either dead, wounded, or fled.

Your PCs will mostly be unable to meaningfully effect this, but that's actually pretty realistic. Small elite groups can make a big difference if maneuvered to the decisive point, but if they are just wandering around in the scrum slaughtering random mooks or buffing their own mooks they aren't likely to actually influence the overall fight much. Your paladin's aura or inspiring bard has the range to provide a slight advantage to, what, 12 peasants (assuming they each occupy a 5' space)? That's simply not meaningful if you are talking about a clash of 1000s.

Same thing with most offensive spell effects: even a tightly packed enemy will only have a few dozen people caught in a fireball. If that's the enemy command tent or their siege engine, that may impact the battle. But in the line it's unlikely to be meaningful, ESPECIALLY if the enemy is mind-controlled and won't retreat despite seeing their friends get cooked.

[Tvtyrant]

I would probably implement a Fog of War mechanic where you can't see or target anything more then 20 squares away, and nor can enemies. No getting mass arrowed into the ground, you hold one part of the line.

Then the party has to deal with waves and get reinforcement tokens. Spending reinforcement tokens nets them a small group of basic warriors. These can be archers or spearmen. The enemy waves get more powerful each time as the enemy commander steers smaller but more elite forces at the party, ending on a couple Pit Fiends or whatever.

This is more realistic because battle awareness was practically nonexistent before modern times, you basically set up your lines with vague plans and marched them forward. Changing tactics was often a matter of hours, and units couldn't rely on support if something went wrong. It also frees you from having to have the party fight 30,000 enemy commoners, no one has time to reposition constantly. It is just going forward in directions or back.

[Kurt Kurageous]

I would probably implement a Fog of War mechanic where you can't see or target anything more then 20 squares away, and nor can enemies. No getting mass arrowed into the ground, you hold one part of the line.

Then the party has to deal with waves and get reinforcement tokens. Spending reinforcement tokens nets them a small group of basic warriors. These can be archers or spearmen. The enemy waves get more powerful each time as the enemy commander steers smaller but more elite forces at the party, ending on a couple Pit Fiends or whatever.

This is more realistic because battle awareness was practically nonexistent before modern times, you basically set up your lines with vague plans and marched them forward. Changing tactics was often a matter of hours, and units couldn't rely on support if something went wrong. It also frees you from having to have the party fight 30,000 enemy commoners, no one has time to reposition constantly. It is just going forward in directions or back.

Great summation. What you are describing in military terms is not just fog of war, but being decisively engaged. PCs surrounded by combatants have, at that moment, only two outcomes, victory or defeat. And for my game, that's not so great because D&D is a game about choices, and the PCs don't have any more.

[Joe the Rat]

I've worked on a viable swarm template, but for the purposes of getting something to the table for mass combat, this was my latest experiment.

Medium creature unit (Huge swarm)
HP = 5x the creature HP.
attributes as normal for creatures involved. Units can share the space of other creatures.
Units take half damage from weapon attacks. charm, enchantment, paralysis, etc. requires a mass version to affect a unit.*

Actions: Until receives the normal attack & multiattack options as the member creatures, as well as a swarm hit.
Swarm Hit: range 0 (within swarm), or as normal (reach and missile) - use the automatic damage rules for mass attackers from the DMG. apply the damage for a full multiattack sequence if applicable.
(Rather than calculating for each opponent, I calculate the autohit AC for 5 attackers, and assign that. Individuals with AC above that will be missed on the swarm hit)
Attacks are 2x normal damage dice, reduced to normal damage dice if reduced to half hp OR a swarm hit is used that round.

Special: When unit is "bloodied" (reduced to half hp), check morale.

I used swarm damage resistance to capture the area affect is more effective aspects, though it does open the entire "firebolt is better than crossbow" angle as well.
Bringing the unit to 0 hp does not mean killing everyone - instead it means you've broken the unit - most of the members are dead and/or injured, and the rest flee. This is more or less how swarms should be treated.
If the density is too high for your tastes, reduce to 4xhp and assumed 8 members.

*-I like to include a leader in each unit - Wis (Insight) or Wis (History) will let you identify them. Targeting them specifically with disabling effects will remove a unit's actions for the next turn.


Note that this is for fighting Unit vs. Players, or player controlled units. If you are just doing big NPC war numbers, use the mass combat autohit, and figure out how many damage instances are applied. remember to give dis/advantage for environmental and tactical situations (effectively +/-5 to the to-hit modifier).

[SociopathFriend]

For a quick gut-check response I would just figure out the 'average' stats of each combatant and then have the PCs steadily influence the outcomes of those combatants.

For example- Hobgoblins vs Guards

Hobgoblins:
AC 18 (with shield)
HP 11


Guards:
AC 16 (with shield)
HP 11

Same statline but Hobgoblins have Martial Advantage and Guards do not.


I would then arbitrarily figure out how many individuals I wanted each side to count as. So if I had 400 Hobgoblins and 400 Guards- I could say each part of the battle the PCs help with is 20 of each.
Each individual battle would be statwise a 1v1 between a Hobgoblin and a Guard- with the PC able to participate.

For each 'round' a PC is helping a given Guard unit against a Hobgoblin unit- that given Guard unit (likely) wins. For each round a PC isn't helping a given Guard unit- that unit is 'killed'.
Because the average comparison between the two armies is favorable to the Hobgoblins.

If all the Guard units are destroyed- the number of remaining Hobgoblins has to be fought by the party at once. If all the Hobgoblin units are destroyed- the number of remaining Guards are the survivors.

For multiple creature types- just repeat.

[Kane0]

I remember taking another look at the old UA last year and making some modifications

https://drive.google.com/file/d/1Jui-1jfmsLJRiR-ryYLOoX2g_nPOIFyB/view

[SirDidymus]

Birthright had rules for mass combat back in 2E, if you can find them. If I can remember, they'd be adaptable to the edition easily. I'm not sure they'd be a good fit though, if I remember right Adventurers were just able to give a bonus to whichever unit they were with.

[skyth]

Personally, when I had my players take part in a big battle reclaiming a dwarven fortress from some orcs, I gave them objectives - They were to take the entrance so the rest of the army could enter the city and then hit an important objective after that.

Treat them like special forces rather than line combatants. The result of the battle is more narrative.

[Melphizard]

When it comes to large battles one of my key issues is the fact that the party has little reason to not just begin chucking fireballs onto the enemy army's forces so I typically make there be a good reason for that and try to also give them a place in the fight. Thus, I have the enemy army's leaders be at the front of the charge to meet the party head on whilst both armies avoid the people who huck fireballs and battle all around the enemy party and the player party. I then add a version of layer actions for both armies that will cause things to happen to the player's fight both beneficial and negative.

Ex: The enemy army of goblins lets loose a barrage of arrows, roll a dexterity save DC X or take X damage.
Ex 2: Your goliath forces let loose a warcry and call upon their ancestors in a ferocious charge! The power of their ancestors emboldens you, granting you 10 temporary hit points for 1 hour. For the same Duration, you are under the Effect of the bless spell (no Concentration required).


Doing this personally has led to a pretty epic fight that my party and I enjoyed. Some other things to add are maybe swarm statblocks for troops (as someone already mentioned in this thread) that could join their leaders in the fight or vice versa if the party looks like they may desperately need it.

Generally though, if an enemy army looses its strongest fighters whilst the other army still has the people who can throw flaming balls of death on a whim it will cause either moral to loosen to the point of mutiny/fleeing or allow your own army to be bolstered and have their morale increase dramatically.

[Cheesegear]

Generally though, if an enemy army looses its strongest fighters whilst the other army still has the people who can throw flaming balls of death on a whim it will cause either moral to loosen to the point of mutiny/fleeing or allow your own army to be bolstered and have their morale increase dramatically.

So in effect my plan is to more or less have two narratives going on at the same time:

The Macro Battle
The pitched battle, where each square represents a 25-foot square? So, let's say, a Swarm of Gnolls takes up one square, but represents approximately 20-25 Gnolls. Or, a regiment. A Regiment of Gnolls. The enemy leaders, spellcasters and other special rallying points can be found in each Regiment, as I've prepared. And those 'special units' can give any Regiment they join, special abilities. Those regiments clash with other regiments and things happen. There will also be special regiments, where say, two Huge Giants and a Dire Wolf ((9sq.*2)+4sq. = 22sq.; Yeah, my maths checks out), makes that particular square.

The Micro Battle
The players, can join any regiment they choose. They can join a Regiment of Guards, and the players can dictate where they want to go. When the players slam themselves into an opposing square, we go back to the skirmish; The PCs vs. 20 Gnolls, with an enemy spellcaster on the other side as well, but also, the players have 20 Guards with them to run interference, and I give each player maybe 4-5 Guards each they control. We run the combat as normal. When the combat is over, the action 'zooms out' again and we go back to the Macro scale.

The Macro Battle
I give the players control over their side. I take control over my side...I run some sims. I let the players roll some dice, and then I check where the players are and what they've run into during this portion of the battle. If their Regiment was wiped out, do they join a new one? Do they keep count of how many Guards didn't die in the skirmish, and go to rejoin with another Regiment?

Back to Micro
Over time...My narrative hope is that there's 1 or 2 individuals (e.g; Guards) that the players are desperate to keep alive, and keep bringing with them as their Regiments die and reform, and join new Regiments.

So overall, we switch between the Macro and the Micro battles, and the players are definitely taking part in the battle, as it happens around them. But the players are also choosing where they want to go, what they want to join with, and what they want to fight:

Mechanically it will look like this:
- Do you want to fight 25 Orcs?
- Do you want to fight 25 Gnolls?
- Do you want to fight 25 Duergar?
- Would you like to fight two Giants and a Dire Wolf?
- Would you like to fight the Adult Green Dragon?

...Yes. Some fights will be easier than others. That's intentional. If the players don't engage the hard fights (e.g; The Dragon), that means that during the Macro Battle, an NPC Regiment will have to deal with the Dragon, and I can tell you, that probably wont go well.

You can have:
- Dwarf Veterans with Battleaxes and Shields
- Human Knights on Warhorses with Lances
- Two Treants and a Dryad
etc.

That being said, if the players want to engage the Dragon, they can bring Knights with them. We all know that a flying Dragon that refuses to land is a pretty big problem. But you've got several Knights to take the brunt of the damage for you...And their Warhorses will die to the Dragon Breath for sure...And of course the Frightful Presence. Maybe the Dragon has Expeditious Retreat and can literally zoom through the battle line during the Macro Battle.

The players will get to choose whom they fight, and whom they fight with. But whatever skirmish they don't choose, still happens around them. And ideally, I run the sim for that skirmish, as if it did happen. But what rules do I use? What rules do I give the players? How do I run that sim?

[loki_ragnarock]

Legend of the Five Rings has a *very* good system for mass battle through the lens of individual characters.

Go find that. Read it. And see if it sparks some ideas about how things go.


For me, one of the things that I like about it and would Frankenstein into any such encounter; if you are in a pitched battle, you take damage. Arrows are flying, bodies are crunching, ballistae are kathunking, fires are a' ballin', and you have set yourself in the middle of it. How much damage you take from this incredibly hostile environment has a good deal to do with where you position yourself in the battle; if you are going into the thick of it, where the fighting's worst, you take more damage. You also get the hardest random encounters... usually. But that's also where your actions are most likely to bring you honor, glory, and impact the outcomes of battle. If you're sitting at the edges of battle, it's safer... usually. You take way less damage per battle sequence, your random encounters are (usually) pretty tame, and your impact is reduced.

I'm not proposing a one for one; the inherent damage of battle can be soaked by your armor in LotFR, and there isn't a direct analog for that in this system.
But taking a look at that system will give you some *ideas* about how to do it.