Running a war game?? Seeking advice/guides/resources

[Jarmen4u]

Hi all, I've been running a game set in Eberron for about 3 years now, and my party (13th level) is reaching a sort of climax in the story, where a currently unknown force suddenly appears and begins waging war on Khorvaire. The party has a keep and a small army, and the 5 nations are there, still crippled from the Last War, possibly as targets for this massive enemy force. Thing is, I've never actually run a warfare-style game before, and even though I have the general flow in my head, I'm not sure how to make this... fun? Or how to run it at all, logistically speaking.

Are there any resources that I can look at to help? Or do you have any personal advice to share? I do have a plan to leave a sort of "death star exhaust port" solution for the players to cut the head off the enemy force later on, but I'd like them to experience some hopelessness and warfare first.

[Silly Name]

The Heroes of Battle splat has some decent advice on running a war from the POV of player characters, in my experience. Other official 3.5 resources include Miniatures Handbook, with rules for running skirmishes between armies, whereas Complete Warrior has a short section on tactics and suggestions for DMs on how to run a clash of armies. I prefer HoB, overall, and I was never particularly satisfied with the MH skirmish rules.

My two cents: D&D is a game that works best when focusing on a small party with a clear objective, fighting their way through a dungeon or the wilderness to obtain their goal. Pitched battles can be run, focusing on the impact of the player characters, and so can large scale wars, but you need to keep in mind that the PCs are still the protagonists and they want kick down doors and beat enemies, not stay cooped up at the capital awaiting battle reports. If your players want to play general, let them, but don't get fixated on mechanically resolving things: use imagination and logic, let them apply their ideas, and focus on the many aspects of war only as necessary (i.e., if you don't want "feeding the troops" to be a problem, then it isn't! If your players want to focus on grand scale plans rather than running singular battles, do that!)

[Yahzi Coyote]

Generals of Prime attempts to turn army units into single large creatures, so you can just have a regular battle between your party and companies of pikemen and such.

I've used it fairly successfully so far.

[Saintheart]

Wait, wasn't there some D&D supplement that addressed this?

Spoiler

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[Buufreak]

Fields of Blood is a 3rd party supplement that does rather well at taking the 3.x engine and converting it to an RTS-esque format. Give it a look if you like.

[Fizban]

There are easily half, probably a full dozen of different takes on mass-battle rules for 3.x alone, across various books. And they all come down to two things: making up some entirely new system for the "mass" part, and some way of being influenced by the actual 3.x rules. These two points are on a sliding scale, since more of one forces less of the other.

None of them I have read have ever satisfied me. Either they're completely divorced from the actual rules of the game that the players have been using, or they're such a minor scale-up that it's hardly a "mass" combat system at all. Worst are those based on the Mob template concept, which manages to hit the worst of every aspect (turning "troops" into a blob and then trying to retroactively pretend they were troops).

Even Heroes of Battle's minor additions (it doesn't actually have mass battle rules at all, basically just adding some morale, volley, and bombardment rules) still have critical failings- their volley rules explicitly ignore armor when one of the major factors of armor was protection from arrows!

So first you have to ask yourself what you even mean by "war game." Do you want mass battles? How big of armies do you want? Do you want them to have realistic sizes, do you want to include the effects of magic on the setting, what effects do you think magic *has* on the setting? Do you want some sort of strategy game base building resource gathering army production game?


Since I want the game of DnD to actually use the rules of DnD, I've come up with what is little more than a few shortcuts:

Spoiler: Fiz's "mass battle" rules

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Rather than some template or mob statblock or entirely different system that fails to mesh with actual DnD combat, here's a set of modifiers/abilities/whatever that can be applied to speed up combat with large numbers of weak foes:

• Not just any band of cutthroats: These rules are only used for proper groups with martial unity. They need not be suicidal fanatics, nor cowardly conscripts, but they do need to see themselves as part of the same whole. A military, miltia, tribe, or something similar, where the individuals know and trust each other, even if they don't actively practice advanced combat tactics. The primary features of these rules are simply deciding not to bother rolling for Aid Another checks, and the assumption that the individuals will arrange themselves in the best formation to benefit the group. Bad guys that would gladly stab each other in the back, are working under duress, etc, are not suitable for "mass battle" rules.
• Morale: most masses of troops are subject to morale checks as Heroes of Battle. This generally means that eliminating half or more of their number has a high chance of causing a rout of those left alive.
• Fodder: foes do not automatically miss on a natural 1, so a sufficient attack bonus cannot miss. Rolling to check for crits may still be significant, for the morale effects of instant kills, or more monstrous troops.
• Unit Movement: take their turns all as one or in groups as desired by the DM, subject to any initial group initiative rolls. Their movement happens simultaneously and allows them to place all individuals wherever they are most advantageous without "sequencing" problems as long as the individual has enough speed, but their attacks must also be taken simultaneously before or after movement. Thus, they gain no extra attacks beyond what the available positions would normally allow. They trigger attacks of opportunity normally.
• Group Tactics: always succeed at Aid Another checks for each other, and usually focus all their effort on a single attack, resulting in one attack per round with +2 per additional body in melee range. This bonus cannot exceed +18, but units with reach weapons and a sufficient surround can split their bonus between two attacks as desired. Flanking bonuses still apply.
• Defense! Defense!: Some or all of the individuals threatening a foe can choose to Aid defense instead, for an automatic +2 AC per body, but this lasts only for a single attack and gives up their main advantage. The bonus may be applied to whichever individual is attacked first, or to someone specific. Neither case affects the group's effective initiative.
• No AoOs/Braced Only for Charge: Group coordination prevents them from taking attacks of opportunity (to reduce rolling). However, the group is always considered braced against a charge attack and can make this attack with their Group Tactics bonus. A group which makes a braced for charge attack gives up their attack (or defense option) on their next turn.
• Best of the Rest: negative effects that don't affect the whole group are greatly mitigated, because those individuals still succeed at Aid Another automatically, while individuals without penalties make the attacks. Similarly, positive effects which don't affect the whole group are still useful as those individuals become the tip of the spear, making the main attack while the others Aid. Track the position of individuals with such effects, positive or negative, so that they can be ignored, targeted, or held in reserve as desired.
• A Champion: for the same reasons, individuals with better armor or weapons, officers with a few extra hit dice, or even just the one guy with a higher base hit point roll, may be present as part of the unit and used as desired.
• Volley Fire: The primary use of large contiguous archer groups is to negate the chance of missing at long range due to range penalty, but an arrow is just as deadly when it comes down as when first fired*, and a major purpose of armor is protecting against arrows. Change volley of arrows rules: a contiguous archer unit can be as large as desired, and the leader directs them by rolling an attack at their full bonus against a target square (AC 5), with range penalties. Creatures within in the area of a volley attack, whether successful or splash deviated, are subject to a single attack per square they occupy, no more and no less. This attack is made at a base of +0, modified only by weapon properties carried by the whole unit, and is not subject to miss chance or increased damage from feats or features. There are no reflex saves, and armor is not ignored. Dexterity and Dodge bonuses mostly apply as long as the targets are aware, but bonuses from fighting defensively or using the Combat Expertise feat or similar abilities, do not.
  *Actually it's not, but in DnD it is.
• Concentrated Fire: as with Group Tactics, a group of archers firing on a single target instead make a single attack with a +2 bonus for each additional body, to a maximum of +18. Abilities such as Deflect or Block Arrows instead reduce this bonus by half?

This can be used for PC-appropriate skirmishes with dozens or even hundreds of opponents. Depending on just how finely you track their individuals you can run on actual detailed maps, or in broad strokes with masses of X guys blobbed on a zoomed out map. Essentially I'm just saying that if you're running at faux-medieval scales, you just run the dnd like actual dnd, using your knowledge of the game to upscale and smear when necessary, with the "battles" or "campaign" being a series of "dungeons" where you've set the initial conditions and planned for how the players can interact with it. Remember that encounters where the PCs are never in danger and expend no resources are worth no xp- and enemy troops could very well be the equivalent of a climb or jump check (or Fly spell), a terrain feature.

If you want battles with thousands clashing in the field simultaneously, you'll need something for simulating troop movements of that size, but at that point you're not playing dnd anymore: you're playing whatever the new game is that simulates those large troop movements. And inevitably some PC will be annoyed that none of their normal character abilities actually matter.

Of course, if you've got normal 1HD humanoids, they should generally be no threat to the PCs without some sort of supernatural morale: the PCs can literally kill them all day and build walls out of the bodies, which means the troops don't fight them (but again, the fighter will want to charge in and break a giant formation all on their own, and some caster will have a spell that should totally matter on that scale if you just follow the math. . . ). And if you've got armies of things that actually threaten the PCs, then the PCs need similar armies of their own.

[RNightstalker]

It's definitely a challenge, an attractive challenge sometimes, to want to do something like that on a larger scale, but it's a crap ton of work. There's a lot of rolling and waiting involved when the DM gets to play the army's turn. A simpler form could look like: making one roll for determining how your character does in said battle, where a natural 1 is death and natural 20 is having bards singing songs of your exploits for a thousand years.

Keeping that in mind, an OoC chat could be a great asset in finding out what the players are comfortable doing. Do they too want to have to fight off hundreds and/or thousands of enemies in normal initiative rounds, or would they rather simplify the larger battles to highlight the smaller but more integral encounters?

The bottom line is D&D isn't designed for combat on a grand scale, so in order to do it right will require houserules and cooperation all around.

[Efrate]

I like the HoB approach as you essentially design objectives that pcs need to accomplish. Mostly because it actually matters. A level 13 martial just stands there and casually slaughters an entire army of lvl 1 humanoids kind of effortlessly. Even without some kind of magic giving tons of reach and AoO or AoE effects. Which kind of instantly break any army of run of the mill conscripts.

5 armies. Have 3 objectives per army, plus getting to said objective. Scout positions, disrupt supply chain, rescue prisoners, destroy command. Something like that but vary it.

Your sneaky types go out at night get the layout and disposition of forces with a variety of skill checks, then assign forces to attack in a good way.

Your pcs find their food supplies and wreck it via magic, poison, refuse, whatever, which they know the key locations of because of scouting. They face a quartermaster and some guards likely. Depending on how good your scouting was this varies in difficulty and number of opponents.

Your scouts also founds the ViP prisoners, with the same caveats of depends on their skills vs. Whatever DC you think is appropriate. They can use distractions, social skills, or brute force to secure them, then hand them off to retainers to escourt to safety.

Finally after that you strike the generals, whose strength you may or may not know accurately, and their elite guards. The general group gets morale penalties based on how successfully you did all of the other things, so you can scale them up or down as needed. Once the army hears of their generals defeat they break and scatter being soundly routed by your troops.

At any point in time throw a random monkey wrench because information was not perfect. Reinforcements arrive, your lines were broken in a counterattack and you need to help or what have you.

Have all the troops activity be in the background and focus on things the pcs generally have a direct hand in, give all your members time to show their specialty and its not too bad to run, just requires a lot of prep work.

[Jarmen4u]

I appreciate all the resources guys, I'll look into them! We've never really done anything paperwork heavy, so I probably won't lean too hard into the "feeding armies and tracking supplies" side of things.

The nations of Eberron would most likely get involved somehow, so they would likely make up the main defensive force against this enemy, though they would probably lose on most fronts until the PC's can find a way to make a strategic difference. They'll probably end up commanding their forces indirectly and making a few appearances on the battlefield, but long-term they'll need to cut off some strategic heads or attack the heart of the enemy directly. If they, for example, infiltrated the enemy's capital and blew up their central command, what kind of effect would that have? Obviously it would cause problems, but I would assume some lieutenants or lower-level commanders could take over in some limited fashion. I guess I don't read enough literature of this genre to really know what kind of objectives I should set for them to aim for.

[Silly Name]

If they, for example, infiltrated the enemy's capital and blew up their central command, what kind of effect would that have? Obviously it would cause problems, but I would assume some lieutenants or lower-level commanders could take over in some limited fashion.

This heavily depends on how the chain of command of the enemy is structured, and how strong it is, meaning how much people are going to follow procedure if enough big honchos bite the dust all at once.

In a fantasy, pseudo-Medieval/Early Modern world, high-ranking officials who survive this attack will probably try to carve out their own realms out of the chaos the kingdom has fallen into. Some fervently loyal ones may search for a heir, but infighting is bound to happen. Personal charisma and ties are going to matter a lot here, drawing forth allies and keeping troops loyal in the face of such a crisis.

I guess I don't read enough literature of this genre to really know what kind of objectives I should set for them to aim for.

Adventuring parties make for good Special Mission Squads, if deployed directly. They can sneak in enemy territory and take out critical objectives, such as leaders or powerful weaponry, disable magical devices, and so forth.

At the generals' table, the goal is to beat the enemy. Aggressors usually want to occupy and control a territory or take/destroy something, defenders want to, well, defend those things and may also end up taking the fight to the aggressor and make them stop.

Realise what the objectives of the various sides of the conflict are, establish why they haven't been achieved yet, and what obstacles may be needing overcoming to reach those objectives. Once you have goals, you can analyse what solutions the PCs could seek. What's the core conflict? Why are the people participating in it doing so? What are their methods, their strengths and weaknesses?

[pabelfly]

I ran a one-shot between four players fighting against fifty or so mooks and several important NPC boss combatants. Pre-written module.

I kept the mook enemies in groups of nine, so each nine had the same initiative and moved together, but kept track of their HP separately. I used different-colour counters for the different monster-types, and had about three different monster types, plus the bosses. The mooks had around 45HP, and some of the players did a little less damage per round and others a bit more, but I fudged the HP slightly so each melee person (and the Druid's animals) was one-shotting a mook each turn, and the party mage was doing solid AoE damage against one of the groups each turn.

Very long combat session, with one combat being roughly the length of two to three regular encounters, but the players won and all had a good time. If I run an encounter against a small army again I'd do something pretty similar.

[tiercel]

Part of what makes war hard to run in D&D is asking yourself

* what resources do armies have
* what resources/tactics can armies reasonably anticipate (and try to counter)

If bards exist in your campaign world, armies will have them. Especially true for Dragonfire Inspiration bards as well, and duodecaduple true if War Chanters exist (yeah, sure, NPCs with 10 levels of War Chanter are and should be rare but it only takes one).

Also: dragon shaman vigor aura.

Also: DRUIDS (the druid spell list is pretty much king of obscenely large AoEs, starting with entangle at first level.)

Also: sure, yeah, fireball and the like (and armies that don’t have a protocol about taking incoming magical AoE damage aren’t armies, they are necromancer fodder)

Also: fog. Your bog-standard spear-and-shield melee grunt doesn’t matter if he can be targeted at distance by arrows, siege weapons, AoE damage and disables, flying creatures, etc etc, so breaking line of sight (with terrain or weather effects or outright literal, magic fog of war is pretty yes).

These kinds of considerations let you start to set what the battlefield might even look like. Then, also, consider what a high-fantasy enemy general might have as an “oh crap, it’s PCs” protocol, other than “send waves of CR 0.5 foes at them to try to close to melee”.

[RNightstalker]

I guess I don't read enough literature of this genre to really know what kind of objectives I should set for them to aim for.

Think about the LotR movies (the first trilogy). In the Fellowship, the main battle near the end of the movie the orcs were supposed to kill the non-halflings and capture the halflings alive. Only one of the non-halflings is killed and half of the halflings are captured. The main purpose wasn't complete destruction.
In The Two Towers, Helms Deep was the main battle. The main characters were there to influence the army and make key differences. Legolas couldn't kill the kamikaze that lit up the black powder bomb. Aragorn and Gimli helped save the main causeway door for a while. Gandalf led the cavalry to the rescue while the others helped keep people alive to be rescued. Without their involvement Rohan was doomed.
In the Return of the King, it was similar to Helms Deep. Gandalf and Rohan helped keep Gondor alive until Aragorn came with the key reinforcements. In the Battle of the Black Gate, the main characters job was to stay alive long enough to buy time for Frodo (and Sam) to capture the ultimate objective.

Pretty much the same process goes through all wars/battles. What are the primary, secondary, and ultimate objectives? Answer those questions and you can build encounters around that.

[Thane of Fife]

I'm not really that knowledgeable about Ebrron, but my understanding is that it is largely inspired by the pulp fiction of the 20's and 30's, with the Last War as WW1. With that in mind, I would recommend that you abandon any idea of making your war look like a typical fantasy/medieval war and just go whole hog with making it resemble WW2. Take full advantage of all the magic in Eberron to show warfare on an industrial scale.

An example of how something like this could go:

The Enemy show up. With lightning speed they overrun and conquer one of the five nations. Don't even let the players know it's happening until it's too late. This shows the Enemy as a big deal. Of the remaining four, two band together against the Enemy, but the other two are in a stand-off with each that keeps them from joining. Now the players get involved, asked to go on a diplomatic mission to the non-allied powers to get them to join the alliance.

Ideally, the players succeed at this, but while they are doing so, the Enemy overruns one of the two allied nations, leaving the three remaining to face the Enemy. They ask the players to go behind enemy lines and wreak havoc in the occupied territories. The adventure has not offered the players much choice thus far, but now it can give them more agency as they are presented with many possible ways to sabotage the Enemy's war effort: blow up bridges and rail lines, set up a resistance, steal secret plans, rescue POWs, etc.

Along the way, the players can hear news from the front - at first, things are going badly, but as the players succeed, things start to go better. This news can also help the players decide what to do. For example, if they hear that the war is getting intense around some specific location, they may attack rail lines to that location or steal the plans for the attack. Or they might decide to take advantage of the Enemy's distraction to do something elsewhere.

In any case, as the war starts to turn against the Enemy, they intensify efforts to stop the players, maybe trying to bribe their allies or attack their resting places. Ultimately, as the allies grow closer and closer to victory, the players catch wind of some super weapon being deployed by the Enemy to turn the tide of the war, and you can have a big final adventure as they destroy it or something.

And thus, we've managed to get through a fantasy war without the PCs ever being directly involved in a major battle.

[Fizban]

the LotR movies

Having recently read a massive series analyzing the military matters in both of those battles (link to Helm's Deep, link to Sige of Gondor within), with a side of bringing up all the differences between the movies and books, can't say they're a good pick if you want your battles to be realistic in any way. The books are apparently far more realistic than one might expect, Tolkien actually having been to war and also being a scholar of the appropriate history and middle earth having essentially zero "DnD magic"- troop movements are realistic and significant, the focus is on cohesion and leaders knowing what they're doing, Saruman loses because in their hubris they thought they could build an army out of nothing and have no actual battle experience or plan (and the heroes weren't actually needed, and Sarumans ultimate goals were doomed to fail even if they did take Helm's Deep), and the Witch King's plan is great under the circumstances but their troops never enter the city and are once again morale broken by inferior numbers landing a series of shocks thanks to good troop management.

The movies make a bunch of changes that comparatively turn those battles into action shlock, by making a bunch of changes for movie-ness. Very good action shlock (far better than something like say Game of Thrones) whose movie-ness makes those changes what people usually remember, but still. Which does make them an excellent fit for Eberron's style, since it's basically nothing but style with no real structure holding it up.

Take full advantage of all the magic in Eberron to show warfare on an industrial scale.

Which is the sort of thing sI mean- the "magic in Eberron" doesn't actually support anything on an industrial scale, or indeed, anything at all. It's exactly as easy or impossible to disrupt as the DM wishes, because it never actually makes any definitive statements. The worst example as always being the magical trains: there's paths, and costs for cars, but no cost for the magic rails. So that happens at speed of plot, not because the DM uses Eberron to assign an appropriate speed, but because Eberron is all style and leaves almost all critical information up to the DM. Thus much like the LotR movies, "Eberron" warfare must rely, and indeed can only consist, of a series of action setpieces after which the heroes just happen to turn the tide enough to win the war.

To be clear that's perfectly fine, for an adventure around a war, but it's not what I'd call a "war game." Even Red Hand of Doom is actually pretty grounded in DnD mechanics: their troop totals and level aren't faked nearly as much as you'd think based on DnD level demographics (fudged definitely, but close enough to see the link to the MM entries), their movement is slow and already has assigned values for how the PCs can hinder them and by how much. The horde's assumed overwhelming victory is rooted in supernatural combat assets (the Razorfiend hatchery, undead from the Ghostlord, and an infernal portal) which can challenge the PCs while being unbeatable by normal troops, but which the PCs can cut off at their sources before the battle and then personally counter the smaller numbers. Even then, if they don't happen to have cleared out enough of the horde's leaders, the horde rallies and wins by force of numbers. The main things missing from RHoD are values for the PCs directly bleeding the horde (since the writers seem to think that's impossible but DnD magic says it is), and direct accounting of DnD magic and nebulous "training" efforts on the main battle (which can be waved off as being accounted for in how a bunch of peasant conscripts with no gear actually stand a chance against the horde soldiers).

Shadowdale: The Scouring of the Land tries to be another RHoD, but it takes place at a higher level, in a setting that actually does leverage some DnD magic, with a smaller horde, with more bogus level demographics, and to add insult gives a detailed map for the enemy fortress and has a mission where the PCs must enter it, but refuses to give any details on encounters they might face and tells the DM to make it up. But then, S:TSotL is more focused on its ongoing campaign arc of blah blah shadow weave blah blah, with this occupation war basically a side show in the campaign.

The War of the Burning Sky is a 1-20 campaign that I think nicely showcases some of the problems. At the beginning, the PCs are significant because they're chasing a mcguffin/are the mcguffin. Eventually there's a small war with an interesting scene that has the PCs are part of a big line of other adventurers and monsters, where both sides just send their best stuff straight at each other to get things over with- very artificial in one way, but also reasonable and effective for saying the PCs are worth X much compared to the unspecified other PC-tier stuff, and then there's various details about the encampments and the PCs role in gathering enough troops on a time table before the battle. This occurs around the same levels as RHoD and S:TSotD, the "past 5th but not more than 10th" range where this sort of game works well. At higher levels, the PCs involvement is reduced to "go to this dungeon and do X," until the very end, which I haven't read in detail, but apparently involves a mass battle using mob-template armies of ridiculously high level NPCs that couldn't be sourced from anywhere in the campaign setting, in order to let the PCs still actually fight directly. In short, WotBS has a good compromise early on, but also knows that a "war game" needs to end with a big battle where the PCs can take the field, except it goes to far too high of a level for that to actually work in DnD 3.x.

[Jarmen4u]

Sorry for the late reply, had a wild week. I really appreciate the detail from your post, Thane. I'll probably use that as a jumping off point for how I want to structure this.

And Fizban, I played in a RHoD game many years ago; I was thinking about digging into that module to see if there was anything worth using. I'll also check out Shadowdale and War of the Burning Sky.

One other thing not really accounted for in the otherwise great structure laid out by Thane: the Lord of Blades and his army. They would most likely not ally with any force due to their overall objective being the end of humanoid life on the continent, but the Enemy TM would most likely wipe them out with little trouble. What role, if any, would they serve, other than fodder? Maybe the party is leading an expedition to find his base of operations only to happen upon the ruin of his last stand?

[RNightstalker]

can't say they're a good pick if you want your battles to be realistic in any way. The books are apparently far more realistic than one might expect, Tolkien actually having been to war and also being a scholar of the appropriate history and middle earth having essentially zero "DnD magic"

We're trying to argue realism on a D&D forum thread?? And here...we...go!

I would respectfully disagree with your assessment of the military matters mentioned. But to not hijack the thread, I mentioned LotR for a well-known base reference that most will have seen. Yes the battles are quite different in the books, especially Helm's Deep. It's the standard way to tell most stories: plot, conflict, resolution.

[Fizban]

But to not hijack the thread, I mentioned LotR for a well-known base reference that most will have seen. Yes the battles are quite different in the books, especially Helm's Deep. It's the standard way to tell most stories: plot, conflict, resolution.

Indeed, no need to hijack a thread- Deveraux's article series do the job far better than I ever could, which is the point. The topic is enough to write a book about and they basically have.

We're trying to argue realism on a D&D forum thread?? And here...we...go!

Realism is a word more people understand than verisimilitude. In any case far more of DnD's rules are far better grounded in realism than most people give them credit for or even realize, particularly the parts that have nothing to do with the extra layer of DnD magic. Stories/ideas/plans/etc that start with "it's fantasy/a story/not supposed to be realistic" frequently end up being bad stories because they don't make any underlying sense, and people notice even if they don't notice. A TTRPG that you spend hours and hours planning and playing over months and months is not the sort of thing I would expect people want to be remembered as "oh it didn't make any sense but the DM gave a really nice speech that one time and described the action really well so my brain tuned out and I just went with it."

One can't claim that DnD magic should radically change warfare so much that it's not "medieval" anymore, and then refuse to examine exactly how, and you can't examine how without knowing how it actually worked before and why it changed. Even the "Eberron" track of shaping it generally like real-world history and fiat-ing in magical analogues for x/y/z so you can skip straight to dropping the characters into fantasy versions of historical narratives, still respects that by the fact that it's using sticking to historical narratives. Just from the opposite direction of forcing the game to match from the top down instead of building up into a realistic in-game history from the rules-up.

[Bonzai]

There was a cartoon in the 90's called Exosquad. To me, it provided the best example of how to run a war in a D&D campaign. The party aren't front line fodder. They are elite operatives. They go on missions and raids that help shape and determine the course of the war, not seeing who can rack up the biggest kill count on the battlefield.

[RandomPeasant]

For my money, the scariest force in D&Dland is Necromancers. Undead armies have no logistics train, do not break under fire, and obey orders perfectly. And the suite of immunities undead have lets you do all kinds of scary stuff with your magical support. Does your army want to fight under a stinking cloud or cloudkill? How about getting blasted with fear or confusion? Or standard-bearers carrying permanent symbol spells? And that's just the stuff in Core. With a broader sourcebase, a necromantic army is going to be coming in with an artillery corps trained as Uttercold Assault Necromancers, or Zombie White Dragons that keep their best anti-army abilities (which skeletons are conveniently immune to).

If bards exist in your campaign world, armies will have them. Especially true for Dragonfire Inspiration bards as well, and duodecaduple true if War Chanters exist (yeah, sure, NPCs with 10 levels of War Chanter are and should be rare but it only takes one).

That depends on how you model classes and progression. If you assume that characters in the setting are freely choosing classes in pretty much the way PCs do, yeah, every army is going to have Bards and Marshals and Dragons Shamans and whatnot. But that's not necessarily the only, or even best, way of modeling things. To my mind, the better way of thinking of things is like technology. In the real world, different technologies developed in different places and were deployed in different ways at different times and by different civilizations. I expect you'd see a similar thing in D&Dland. Not every country is going to have access to every magical tradition (at first) or be willing to adopt them all equally (both at first and at all). I expect you'd see a progression from the stereotypical Dark Lord commanding his Dread Legions to something that looks more like modern combined arms tactics (D&D dragons are something almost any general in history would have killed for).

Also: DRUIDS (the druid spell list is pretty much king of obscenely large AoEs, starting with entangle at first level.)

Druids are interesting within the magic-as-technology model. Because Druids, by the stereotype, are probably not going to be going in on team "large organized army". Your Rome or China or England equivalent is not going to be able to train and maintain an army of Druids, because those Druids are not going to be on board with a big, organized civilization. That sets up an interesting balancing dynamic that is not really reflected in real-world history.

[RNightstalker]

If bards exist in your campaign world, armies will have them.

Reminds me of the English with drums and bagpipes in the lead...other armies have done similar things.

There was a cartoon in the 90's called Exosquad. To me, it provided the best example of how to run a war in a D&D campaign. The party aren't front line fodder. They are elite operatives. They go on missions and raids that help shape and determine the course of the war, not seeing who can rack up the biggest kill count on the battlefield.

I don't remember that one, when did it air and which channel was it on?

For my money, the scariest force in D&Dland is Necromancers. Undead armies have no logistics train, do not break under fire, and obey orders perfectly. And the suite of immunities undead have lets you do all kinds of scary stuff with your magical support. Does your army want to fight under a stinking cloud or cloudkill? How about getting blasted with fear or confusion? Or standard-bearers carrying permanent symbol spells? And that's just the stuff in Core. With a broader sourcebase, a necromantic army is going to be coming in with an artillery corps trained as Uttercold Assault Necromancers, or Zombie White Dragons that keep their best anti-army abilities (which skeletons are conveniently immune to).

I'm going to need your help planning an encounter...the PCs will hate me, but it will be oh so worth it

[aglondier]

Give the players plenty of scope to effect the large pitched battles before hand. This is where the rogues come into their own. Steal plans, sabotage supplies, assassinate leaders...
Let the players go wild with their plans, and give them the opportunity to cripple the enemy force before the battle. But remember that the enemy can do the same, and the players are very visible targets.

[RandomPeasant]

One thing that's worth thinking about in the context of war in D&D (though retrofitting it into an existing setting would be hard) is the impact of powerful champions, like PCs and dragons. While there's certainly some amount of flex to how much an army of low level characters can do, depending on optimization and tactics, the harsh reality is that a large enough gap can't be crossed. If your army is 1st and 2nd level characters with leaders going as high as 6th level, you're going to lose if you go up against a power that can deploy killteams of even ~10th level adventurers. And that power is going to get crushed if a nation lead by a (near-)Epic level character (particularly a spellcaster).

That has an obvious effect not just on war, but on the norms around war. If a Great Wyrm Dragon comes up to your E6 kingdom and says he's in charge, throwing your people at him in a futile gesture of defiance is just going to get a generation of them killed (and that's assuming he doesn't decide your behavior warrants obliteration). So I would expect that D&Dland would evolve an escalation process that involves steps to check to see if the other side can wipe you out, and diplomatic niceties that paper over brute intimidation to allow smaller powers to save face when a 25th level Wizard decides she wants them to ransack their lands for rare spell components. For example, war probably involves some type of "contest of champions" tradition, where prior to escalating to open conflict, both sides put forward their baddest dude, and if either side judges that the duel went badly enough for their champion, they immediately begin peace negotiations. This is probably a strong societal honor norm, and may be reflected in attitudes towards things like asymmetric warfare.

[Bonzai]

I don't remember that one, when did it air and which channel was it on?

https://en.m.wikipedia.org/wiki/Exosquad

For the most part it was a very well written series. The main characters were crucial to the war effort. And while they did fight in the major battles, they weren't single handedly winning the war by themselves. Instead they performed key missions that shaped the larger war. Things like sabotaging key production facilities, abducting enemy scientists. Etc... To me that is the best way to handle a war campaign.

[noob]

https://en.m.wikipedia.org/wiki/Exosquad

For the most part it was a very well written series. The main characters were crucial to the war effort. And while they did fight in the major battles, they weren't single handedly winning the war by themselves. Instead they performed key missions that shaped the larger war. Things like sabotaging key production facilities, abducting enemy scientists. Etc... To me that is the best way to handle a war campaign.

The issue is that some level 10 characters could kill thousands of level 5 or less characters up to the point they could just solo an army of level 5 and less people.
In dnd 3.5 levels grants growing advantages: even the cr system assumes that 2 more levels means you can fight twice as many opponents of a given level and in practice it can be even worse than that.
So it makes sense in a non dnd world to have the most skilled people sabotage things but in a dnd world the most skilled people can facetank the opponent army and melt through it thus making any infrastructure it had irrelevant and it is arguably a more useful use because it means that your army will take less losses while the opponent army is busy being annihilated in a single day.

[Efrate]

Yeah stuff like cloud kill can destroy an entire army in a few rounds. Even more so if invisible. If you do not do contrivances to make such things not happen, then you cannot have a war campaign, let alone a war session.

Focusing on objectives is the best way to make an impact without just roftstomping armies on the way to the next dungeon. The more mundane/martial members your party has the more you need to lean in that so they feel relevant. Have your plate mail sword and boarder wreck mooks, use great cleave and just chew through a battalion guarding a crucial mountain pass. Your skill users do sabotage and scouting, etc. As long as you have no or limited magic users it's doable. The more magic your players can leverage the less specific objectives and the more "I just eliminate the army" that happens.

[noob]

Yeah stuff like cloud kill can destroy an entire army in a few rounds. Even more so if invisible. If you do not do contrivances to make such things not happen, then you cannot have a war campaign, let alone a war session.

Focusing on objectives is the best way to make an impact without just roftstomping armies on the way to the next dungeon. The more mundane/martial members your party has the more you need to lean in that so they feel relevant. Have your plate mail sword and boarder wreck mooks, use great cleave and just chew through a battalion guarding a crucial mountain pass. Your skill users do sabotage and scouting, etc. As long as you have no or limited magic users it's doable. The more magic your players can leverage the less specific objectives and the more "I just eliminate the army" that happens.

Even some non casters can just go "I eradicate the army" such as a vecna blooded necropolitan dark creature divine minion fighter 2/barbarian 1/crusader 3/rogue 2 is ecl 10 but can probably just hide and kill opponents from far and recover from all taken wounds instantly and is immune to a ton of things and divination does not works on him so you can not spot him when he hides and moves silently with his epic modifiers and snipe your army progressively killing 1 soldier per round without ever feeling tired (so he can kill a total of 14400 soldiers a day).
This character would be incredible for infiltration missions too but why infiltrate when you can kill one opponent per round?

[Bonzai]

The issue is that some level 10 characters could kill thousands of level 5 or less characters up to the point they could just solo an army of level 5 and less people.
In dnd 3.5 levels grants growing advantages: even the cr system assumes that 2 more levels means you can fight twice as many opponents of a given level and in practice it can be even worse than that.
So it makes sense in a non dnd world to have the most skilled people sabotage things but in a dnd world the most skilled people can facetank the opponent army and melt through it thus making any infrastructure it had irrelevant and it is arguably a more useful use because it means that your army will take less losses while the opponent army is busy being annihilated in a single day.

A couple things to consider here. First is resources. Just how many spells can a caster cast? A lvl 10 wizard can throw out 3 cloud kills, 4 fire balls, and an assortment of lesser spells. Then what? In an army of thousands, that's not going to make much of a dent. Second is action economy. That same wizard is putting out a spell per turn. But how many turns are in these rounds? Eventually he is going to get zerged. Especially when he is specifically targeted due to flashy displays. Weight of dice will eventually wear them down. 3rd is that there is probably more than just fodder to deal with. While the party is ripping through grunts and foot soldier, they will gain the notice of the army's captains and Lieutenants. They will have access to just as many tricks and tactics as the party, except the party will already be expending resources. Which brings another point.. withdrawing may not be an option. There is a term for retreating from an active front without orders... and that is desertion. Which leads to my final point... attrition may not be their objective. Maybe they need to protect their commander, or hold the line while the army retreats. Maybe they need to clear a path through enemy formations, or take out a particularly dangerous threat. Any additional twists like this will help make combats more memorable.

[Bonzai]

Even some non casters can just go "I eradicate the army" such as a vecna blooded necropolitan dark creature divine minion fighter 2/barbarian 1/crusader 3/rogue 2 is ecl 10 but can probably just hide and kill opponents from far and recover from all taken wounds instantly and is immune to a ton of things and divination does not works on him so you can not spot him when he hides and moves silently with his epic modifiers and snipe your army progressively killing 1 soldier per round without ever feeling tired (so he can kill a total of 14400 soldiers a day).
This character would be incredible for infiltration missions too but why infiltrate when you can kill one opponent per round?

You could also just roll up pun pun, but I would argue that the campaign is pretty much off the rails at that point and conventional game wisdom is pretty much out the window.

But why go on missions when you can just kill one soldier per round? Oh, maybe while you are taking pot shots, the bulk of the army accomplished its objective. Say.... burning the town you were trying to save to the ground. Or killing the guy you work for. Maybe the rest of your Allies take such heavy casualties that they break and Scatter ending the war. Any number of things could happen that renders the attrition you are dealing meaningless. War shouldn't be a solo sport.

[noob]

A couple things to consider here. First is resources. Just how many spells can a caster cast? A lvl 10 wizard can throw out 3 cloud kills, 4 fire balls, and an assortment of lesser spells. Then what? In an army of thousands, that's not going to make much of a dent. Second is action economy. That same wizard is putting out a spell per turn. But how many turns are in these rounds? Eventually he is going to get zerged. Especially when he is specifically targeted due to flashy displays. Weight of dice will eventually wear them down. 3rd is that there is probably more than just fodder to deal with. While the party is ripping through grunts and foot soldier, they will gain the notice of the army's captains and Lieutenants. They will have access to just as many tricks and tactics as the party, except the party will already be expending resources. Which brings another point.. withdrawing may not be an option. There is a term for retreating from an active front without orders... and that is desertion. Which leads to my final point... attrition may not be their objective. Maybe they need to protect their commander, or hold the line while the army retreats. Maybe they need to clear a path through enemy formations, or take out a particularly dangerous threat. Any additional twists like this will help make combats more memorable.

I say a non caster build then you talk about spell slots.
That build I gave have no spell slots at all and uses no limited resources and can not be zerged because the opponent can not know where he is: not even divination spells would work for finding that character.

But why go on missions when you can just kill one soldier per round? Oh, maybe while you are taking pot shots, the bulk of the army accomplished its objective. Say.... burning the town you were trying to save to the ground. Or killing the guy you work for. Maybe the rest of your Allies take such heavy casualties that they break and Scatter ending the war. Any number of things could happen that renders the attrition you are dealing meaningless. War shouldn't be a solo sport.

That is absurd: missions would not stop the opponent army from burning down the town if they were not stopping from burning the town while you were sniping one soldier trying to set stuff on fire per turn.
I mean if you are killing the supply line which is the next fastest way to stop an army over killing its soldiers then the soldiers would have burnt the town faster because they would not even have been aware of the supply line dying before finishing the deed and none of the soldiers trying to set the town on fire would have been scared from seeing one of their friends dying per turn.
It simply is slower and less efficient for stopping an army to do stuff other than killing it when you can kill this fast day and night.
Also if that character had allies and could solo the opponent army all the allies would have to do would be to go somewhere else and sit(or help civilians evacuate away from the path of the opponent army) while the character kills 14400 soldiers a day.
There is no way the opponent army would not disband quickly from morale issues by seeing so many of their soldiers die per day from an unseen opponent they can not fight while if they actually manage to fight something then they would disband to morale issues slower.

See by making war not be a solo sport you killed your allied army and that is very bad warfare skills.
To put in perspective you could kill the biggest active army in the real life in 151 days (while you would kill most medieval armies in something less than 6 days because they used to be much smaller) with that build and it is much bigger than most fantasy medieval armies but you realise it means that the opponent army can not occupy the country nor can they go deep in your country then come back alive with the spoils of war (and if they do a frontier raid then the stakes are not nearly as important as if they were raiding the capital) so it means that they can not gain anything meaningful from losing their entire army to you which means that the troops would very quickly have morale issues and disband.
Also the 1 person a round was with the assumption that the opponents were standing 30 meters away from each other (which is normal dnd army practice, any sane army should be doing this). If they are not then you can kill more per round with tricks like carrying a small ballista with siege engine enchantments in order to hit aoe so it means that the opponent army is not going to keep soldiers close to each other and so it means that if you are defending an objective (such as the town to burn) that there can not be many soldiers approaching the objective at once and so you can just kill the closest one constantly and it will slow them down massively.

So armies of regular people are in fact not the way to go for warfare: you should only have hidden squads of high level people.