Running Mass Fights in Classic D&D

A common troubling point of DM'ing appears when you run the O/AD&D game, especially in the wilderness, by the book: it's pretty common to encounter bands of malicious bandits, brigands, or humanoids numbering in the hundreds.

OD&D Monster Reference Table

What's the best way to handle these cases, and what is likely to happen? I've actually had pretty good luck in these cases, so I want to share it here with you.


First, I'll point out that this is something I've been wrestling with for a very long time. In particular, I ran up against this in preparing to run the famous World of Greyhawk adventure, Isle of the Ape. The first encounter has the PC party ambushed by over 250 native warriors, with a minimum barbarian level of 3rd, about 30 name-level leaders or above, and 5 trained giant apes. How to adjudicate that? I had the opportunity to ask Gary Gygax about this on the old ENWorld Q&A thread (21st June, 2005):

DELTA: How did you ever deal with the initial combat with some -300 barbarians of varying high levels in AD&D? (Personally, I had to jury-rig a set of mass-combat rules to handle it.)

GARY: Actually, IIRR the PCs from my campaign popped in, surprised the natives, and offed the main leaders quickly, so the mass fled from them. Then the lads ventured past the wall, got a look at things, and got out of there. I don't recall how they managed it, but they left, returned to attack the shaman and his guards, and eventually some of them faced Oonga...

Now, a few things you'll note here. One is that Gary's rough instinct is that defeating a large warrior band comes down to defeating the leaders. The other is that I refer to "a set of mass-combat rules" to handle the situation, that later became my publication of OED Book of War (see sidebar).  


Honestly, this is something I tend to overlook in my analyses, until someone reminds me, but this piece of game rules is very prominent in O/AD&D, and you shouldn't entirely overlook it. If PCs encounter an overwhelmingly large band of enemies, then it's quite likely they can choose to evade and escape completely without any combat. 

In particular, the OD&D evasion chart is specifically biased to make escape easier, the more monsters in the enemy party. E.g., for a PC party of 4-9 people, the chance to escape the upper-end of monster numbers is set at 70%. (Increased in woods, if the enemy is surprised, etc.) Although remember if the PCs are surprised this implies that they're inescapably surrounded by the monsters (Vol-3, p. 17).

A couple notes on that: The exact rules text of the outdoor evasion rules is mangled in both OD&D and AD&D in a way that several details are unclear. Slower monsters can't ever catch the PCs, but by the letter of the rule, the evasion process continues, possibly in an infinite loop forever (see other blog articles for this examination). You'll need to make some reasonable interpretations for yourself to fill that in.

Moreover, the evasion rules are not a panacea to PCs confronting the immense danger of the O/AD&D wilderness. Even in the beneficial case noted above, there's about a 1-in-3 chance that PCs are spotted, cannot evade, and have a 50% chance to be caught by a faster monster army. (With this chance repeated over and over, depending on your interpretation of the rules there.) Conclusions we can make are that the by-the-book O/AD&D wilderness rules are meant only for very high level characters (see stats here) -- or that it's super important to keep a high move rate in the wilderness, to avoid all the galumphing bandit and humanoid hordes on foot.

I'll point out that you'd better explicitly tell your players that this is an option, because the Evasion charts don't appear in the player-facing rules of any early edition (OD&D Vol-3, AD&D DMG). 

Note also that in most versions of the rules, elves and halflings have some special ability to hide from enemies, especially outdoors (see: Chainmail, OD&D Vol-2, etc.). Consider letting those PCs check that chance before turning to the Evasion table for effective members in the escaping party (and thus possibly increasing the chance to avoid: for 1-3 PCs the chance can be as high as 90% base).

If all evasion fails, and you have low-level PCs entrapped by an army of humanoids, consider hand-waving the combat, declaring them captured, and switching the campaign to other PCs until the original group can be rescued, ransomed back, etc.

Ranged Combat

Assuming that the monsters are encountered at long distance, and the PCs decide to engage, then some initial long-distance missile fire may occur. (If evasion is attempted and fails completely, the OD&D text says monsters "will catch" the party, while AD&D says there is a "confrontation" -- I interpret this as being in melee distance, but you might differ.) 

There's an interesting observation on this point in one of my favorite Dragon articles (issue #20, Nov. 1978), by Lyle Fitzgerald, "It's a Good Day to Die (Death Statistics of D&D Players)". In his data, Goblin races at the top of the list, accounting for 10.1% of the 600 deaths documented by player-characters in Lyle's campaign. He writes:

‘Goblin types’, while not being strong individually (although they may have the occasional troll or ogre with them), are usually found in large groups, eager to destroy, and can be encountered practically anywhere or anytime according to the monster encounter tables. Typically, you will come across up to 300 or 400 orcs or goblins, who will proceed to pepper your group with a huge cloud of arrows, wiping out all the low level players and hirelings. Very few higher level players ever get done in by these creatures, however.

Now, I might possibly counter-argue this a bit in that where evidence exists, Gygax specifies a fairly small proportion of any humanoid band as carrying missile weapons -- usually around 20%. In the D&D Monster & Treasure Assortment, the percent ticks upward with dungeon level, but tops out at 20% for kobolds, goblins, and dwarves; 25% for orcs and hobgoblins; 30% for gnomes and gnolls, 40% for bandits (there may be typos here), and 50% for elves (as given in OD&D Vol-2). In the Monster Manual the ratios are 15% for gnolls; 20% for kobolds, goblins, orcs, and hobgoblins; 25% for dwarves and elves; 30% for bandits; and 40% for halflings. 

I should probably write more on that analysis later, but, in summary, I use 20% as the standard proportion of missile weapons among any humanoid group. Looking back to Fitzgerald, the average goblin encounter of around 200 has only 40 missile weapons, and the maximum of 400 has 80 -- e.g., specified as slings in the Monster Manual (and undefined in M&TA).

Then you run into the issue of reasonable long-ranged accuracy, for which I've probably written tens of thousands of words on this blog. At maximum bow-range, hitting an army is certain, but hitting an individual man is impossible -- so a small PC band has a distinct advantage here. I'd let PC missile shots target a random figure in an army at effectively no range penalty; while some significant extra penalty should be applied to the army's shots on PCs.

Looking to Gygax's Swords & Spells rules (a work which is otherwise flawed in significant ways), there are fairly well-considered penalties in this situation for missile fire. If the "target is one rank deep or in order" there is a -30% adjustment to casualties; if the "target is single creature, very large" then -50%; if "target is single creature, about man-sized" then -90%. Perhaps for brevity we might say a PC band of up to 10 people gets the 50% reduction, and we simply disregard half of the goblin shots (so maybe have 20 incoming sling-stones on average). 

At this point what I do is split up the arrows equally to each character or unmounted beast, take a handful of d20's, and go around the table rolling for each in batches. If there are 8 figures in the current example, then that's 2 or 3 shots per character. If the PCs have decent armor, and are being shot by 1-hit-die humanoids, then it's quite likely that only a 20 hits them. I would definitely skip critical hits from Nat-20's in cases like these (further abbreviating the process). I suppose you could have the players themselves roll these attacks and tell you the results, assuming you trust them, to make it even quicker. 

Characters Leading a Large Force

Now we get to engaging in close combat. There are a number of reasons why the PCs might be attached or leading a large armed force of their own. In my games, I've seen this occur when: (a) Players hire bands of mercenaries at the outset, (b) characters have previously defeated a force of bandits and pressed them into service, (c) encounter dice indicate simultaneous merchant bands & bandits locked in combat as PCs arrive, (d) a published adventure sets things up this way, etc.

In this case it does work pretty well to hand-wave the normal types battling the background, and have the PCs face off against the enemy leaders in melee. That's what all those copious notes on enemy leader-types in the Monster Manual are presumably for, right? (I mean, maybe?) And it also somewhat nicely echoes the idea of combat-of-champions in certain older cultures. 

Usually the PCs tend to have an advantage in number of leveled characters in this case -- even if the top enemy character is higher level, the action economy swings things in the PCs favor here.

For the background combat, I mentally apply the Book of War core rules -- every 3 rounds of D&D man-to-man fighting, roll a d6 for each 10 normal men battling; results of 4, 5, or 6 (depending on armor) each indicate 10 enemies down. Easy and statistically accurate. 

Characters on Their Own

Or, it's of course at least as likely that you have a small force of PCs on their own in the wilderness. Let's say they opt out or fail at Evasion, survive the Ranged Fire phase, close with the enemy to do combat, and they're high-enough level that hand-waving their automatic defeat is unreasonable.

First of all, if you're running the O/AD&D rules, you'd better honor the fact that fighters get a number of melee attacks equal to their level against normal-type creatures (roughly 1 hit die or less, but varying a bit by edition). So your Superhero (8th-level) fighter is likely going to hew through 8 goblins every round. My feeling now is that this is a paramount point of balance in those editions -- and also likely the single biggest rules difference between O/AD&D and the Basic/BX/BECMI line, where it was discarded. The types of humanoids that appear in numbers of hundreds are precisely the same types that fighters get their mass-attacks against. If you don't use that rule, then arguably you need to dial down the humanoid numbers by an order of magnitude (as was done in Basic/BX, etc.). 

(Hypothetically, I'm not fond of that rule in a design sense, because I don't like hard discontinuities like the normal/fantastic split in early D&D, it slows the game with lots of dice-rolling, etc. And it didn't help me with Isle of the Ape because everyone involved is above 1st level, hence my asking about that specific case to EGG. But it is a core part of the original rules and you should consider it carefully.)

Secondly, terrain is important. When PCs in my games march around the classic Outdoor Survival map, it's quite likely that they're following a path through woods or mountains (which voids chances to get lost). If that's the case, then the main body of humanoids can easily be bottled up, constrained, and dealt with by PCs facing a fairly limited front line. Probably the humanoid army is in a column formation and not well organized to engage in a fight. (I have small d6 charts of other layouts by terrain type that I use, possibly giving advantage to PCs.)

Third, don't forget about morale. It may not be very well defined in OD&D, or commonly used in AD&D, but it's a critical expectation on the part of the system designers. Recall that the kernel of what Gygax wrote in response to my question was that the PCs "offed the main leaders quickly, so the mass fled from them". Make sure you have a mechanic to your taste to handle this (whether from Chainmail, the OD&D reaction chart, the AD&D DMG system, B/X rules, or my BOW morale system of rolling 2d6 + HD and scoring 9 or more). You could possibly apply it to the whole armed opposition, or one unit at a time (foot contingent, archers, horsemen, etc.).

And if you get to this point, you get the joy of narratively describing a fight of epic heroes vs. hordes of enemies in the way that delights your heart the most. The fighters may wade in with their mass-attacks directly, or come up with other creative responses. I've had PCs with super-strength (from a spell, gauntlets of ogre power, etc.) go up hills and roll down boulders, throw trees to block a path of charge, rip off castle gates, etc., and that's all wonderful. 

Magic-users, of course, get to unleash their best area-attack spells. My interpretation of areas in OD&D is that spells like fireball or lightning bolt can only eliminate up to 10 enemy characters at a time -- but by-the-book it could be 40 characters or even 360 if you let the area expand feet-to-yards outdoors (which Gygax clamped down on later, and in Swords & Spells wrote another ad-hoc rule to limit total damage of such spells: example in the book has a 10th level wizard killing around 40 orcs with a fireball maximum, scaling downward for lower levels). A death spell or a conjured air elemental in whirlwind form could be even more devastating. 

But other options could be using illusions (wand or phantasmal force) to create fake allied units and confuse the opposing army -- maybe wasting a round of mass missile-fire (in fact, that was the origin and etymology of the phantasmal forces spell in Chainmail). Or perhaps targeting mind-control powers like charm, hold, or feeblemind spells against the enemy leaders might be more effective. I pretty much always allow the enemy leaders to be identified and targeted in this way (and likewise assume enemy leaders can target PCs the same way, including fighters in swirling melee) -- more than once an engagement with an enemy force has ended without mass casualties, due to the commander being ensorcelled and told to just walk away. There are lots of options here.


For a mid- to high-level party in classic D&D, there are many possibilities when confronting a mass brigade of armed opponents. They can evade the encounter, bring their own armed troop, probably withstand any mass ranged attacks, and then bring super-powerful attacks to bear in fighter whirlwind-melee and wizard area and mind-bending magics. That's not even considering the option to parley, which I've ignored here (OD&D says monsters automatically attack except in unusual cases, which I've assumed by default). My best experiences have been running things purely narratively without a board or map; this is an occasion when using the "rule of cool", bouncing off player suggestions, and giving at least some chance for effectiveness, can solve a lot of problems for you. 

How has running mass combats in D&D worked for you in the past? Any tips or tricks I'm missing here?

This blog post was chosen as the Wandering DMs Patrons' Pick for February 2021. If you want to get in on future polls for things you'd like to see here, join the Wandering DMs Patreon. We thank you for the support!


  1. It is precisely because of the change over time (and editions) of 0-level troops becoming to 1st, 2nd, or even 3rd level is why I allow fighters to get a number of attacks versus soldier as a ratio. For example a 10th level fighters gets 10 attacks/round versus 1st level and 0-level soldiers, 5 attacks vs. 2nd, 3 attacks vs. 3rd, 2 attacks vs. 4th & 5th level soldiers, and 1 attack per round vs. 6th level and up. In this way the fighter can cinematically wade through and army much the same way the magic-users blows up portions of the army.

    1. That's pretty reasonable. In fact, Gygax has a D&D FAQ in Strategic Review #2 where he uses the word "ratio" that suggests exactly this. (Not that it ever explicitly got in the books thereafter.)

    2. Do you allow the same for NPC fighters? For monsters of multiple hit dice?

      I like the ratio idea, because it reduces the starkness of the dichotomy between fantastic and normal combat. But it could greatly change the play of the game in ways that aren't supported by the published modules, for example.

  2. I have always made a distinction between evasion and flight/pursuit. Evasion allows a party to avoid being noticed all together. Flight gives opportunity to avoid being forced into an encounter when noticed. If the party is noticed and they want to flee I roll for reaction time of the pursuer (0-5 x 5% modifier to being caught), roll for random direction, then I check to see if they are caught. If not caught I roll for the resolve to continue pursuit each turn (another evasion check). When pursuit is over I roll for chance party is lost, possibly modifying chance if flight lasted several turns. Slower monsters will brake off pursuit after one turn and party will automatically evade.

    1. Interesting, I like a lot of that! Agreed that evasion and pursuit seem to be two different cases in OD&D, say (one leading to the other).

    2. It resonates because the military correlation is SERE (survival, evasion, resistance, escape).

    3. Oh, thanks for that, I should read more on that topic. Solid.

  3. Fantastic analysis!

    Do you ever decrease the number appearing when creatures are encountered outside of their lair? This was Arneson's rule, as described in his First Fantasy Campaign.

    I remember that you actually mentioned this on an episode of Wandering DMs, but you expressed the opinion that first rolling for the total "number appearing" of the monsters, then rolling for the percentage of the monsters actually present in an encounter, and finally multiplying the number appearing by the percentage present, was one roll too many (so to speak). But a simple rule like "50% of number appearing are actually present when monsters are encountered outside of their lair" might work.

    1. Thank you! And great ask. At some point I've jotted down Arneson's FFC rule on my DM screen intending to use that regularly (in fact, I jotted down revised NA ranges to simulate the 10-60% cutdown). But I didn't get a chance to really play deeply with that mechanism.

  4. I don't have much to say from personal experience on this, but here are a few points:

    1. You mention at the start of Ranged Combat that you interpret "will catch"/"confrontation" as being in melee distance, yet you then go into applying penalties for long-ranged accuracy to a horde's missile attacks (disregarding 50% of their attacks for around a dozen targets). I know you've supported a scaling penalty for detailed combat in the past (around -1 to hit per 5-10 ft, if I'm not mistaken); do you still apply a range penalty to the remaining attacks, or is that thrown out as part of the "disregard half" approximation?

    2. Interesting that you would disregard critical hits for PCs who can only be hit on 20s in a hail of missiles, when that seems to be the same sort of situation people use for arguing that crit-or-nothing is good (typical example being the PCs' attacks can't find any weak spots in the dragon's hide unless they get lucky to strike at a critical vulnerability). No judgment on my side for or against either approach, as someone who doesn't do critical hits by default.

    3. For Characters Leading a Large Force, I agree completely that trying to play out the entire battle in detail is a tedious mess. Regardless of how the "background" battle is handled, focusing the detailed action on high points is the way to go.

    4. I haven't used the mass combat approach from Flatland Games's rules, though apparently they liked how it worked in Beyond the Wall (in their free From Distance Lands supplement) enough to bring it back for their swords'&'sorcery system Through Sunken Lands. The short version is that the PCs get a preparation phase (skipped if it wouldn't make sense, like a chance encounter in the wilderness), then there are a few parts of the actual battle played out before having each side pick successive successes (e.g. route enemy, destroy assets) and failures (e.g. lose prisoners, suffer losses) based on how it went. It's a more narrative-focused approach than what you're describing here, so I wanted to mention it for the sake of any readers who might want something in that vein.

    1. Thanks for reading this!

      1. My idiom is to declare a shot at either an individual (at full range penalty), or into a mass of bodies (random target, but waive the range penalty).

      2. Oh, weird, I guess I haven't seen that argument often. That's certainly opposite my instinct since forever.

      3. Cool! Worked really well last time I did that.

      4. Definitely people should like at that if they prefer a more narrative approach, thanks for that!

  5. The Hobbit, Robin Hood, and The 13th Warrior both present excellent examples of evading large groups of enemies and also destroying the effectiveness of a group of enemies by taking out the leaders.

    In The Hobbit, taking out the Great Goblin destroyed goblin cohesion, enabling the party to escape from the heart of Goblintown.

    Robin Hood was always going for the leaders first. Cut off the head and the body does not know what to do.

    In 13th Warrior the heroes literally crawl and sneak their way past hundreds of enemies to get into the heart of the lair to assassinate the leader.

    In The Hobbit and 13th Warrior the enemy was eventually able to regroup. Gandalf had to pull a deus ex machina, but in the other case, killing off the last leader caused the enemy to melt away...

    1. Wow, thanks a bunch for those. You know, so many people bring up the 13th Warrior in these discussions, and I've never seen it. Off to put it in my Hulu queue right now.

  6. So if you allow Fighting Men their enhanced number of attacks against 1HD foes, do you do that the "alternative" combat system way of actually rolling d20s and damage dice? Or some simplification along mass combat lines of Nd6, any die showing higher than x eliminates?

    1. Good ask, of course. Obviously either way is legitimate. In theory my default is actually to track the damage; but in practice, high-level fighters are frequently doing enough damage to automatically eliminate 1HD types (1d6 for me), or close to it, so indeed each hit is usually a kill anyway.

      In play I've started out not telling the player that, but then start shouting "They're dead!" as their damage die is in the air, and see how fast they pick up on it. :-)

    2. I don't think I could stomach tracking the damage against that many foes, though it sounds like in practice you just do the N dice anything above target kills, but the dice are d20s instead of 6's.

    3. That's right, it's still d20's, effectively indicating kills. I've learned not to change the usual mechanic for players on the fly if possible. Also (see GelatinousRube's observation below), the last time I did this it was actually the OED Cleave mechanic in use, such that the attacks could continue in sequence arbitrarily until one missed (which seemed to always come up sooner than we'd expect).

  7. Alternative combat system and here's why:

    Thanks to Delta for referring to the following:

    Quoting from The Strategic Review Vol. 1, No. 2 Summer 1975, in the article entitled "Questions Most Frequenlty Asked About Dungeons & Dragons Rules":

    "It is suggested that the alternate system in D & D be used to resolve the important melees where principal figures are concerned, as well as those involving the stronger monsters."

    "When fantastic combat is taking place there is normally only one exchange of attacks per round, and unless the rules state otherwise, a six-sided die is used to determine how many hit points damage is sustained when an attack succeeds. Weapon type is not considered, save where magical weapons are concerned. A super hero, for example, would attack eight times only if he were fighting normal men (or creatures basically that strength, i.e., kobolds, goblins, gnomes, dwarves, and so on)."

    "Note that he is allowed one attack for each of his combat levels as the ratio of one Orc vs. the Hero is 1:4, so this is treated as normal (non-fantastic) melee, as is any combat where the score of one side is a base 1 hit die or less."

    1. And thanks for that quote! Such an important article, really. (It's the thing that convinced me Gary did intend fighter multiattacks vs. normals in OD&D.)

  8. Just a clarification on how this interacts with your OED rules. Would a Fighter with the Great Cleave feat be limited by their level? Would a fighter without that feat still get multiple attacks in mass combat? Great post!

    1. Yeah, you've perceptively found the big problem for me these days; I actually don't know myself. The importance of the fighter-mass-attacks to OD&D game balance is something I've only been convinced of recently, and last time I ran (e.g.) Outdoor Spoliation, I actually wasn't giving the mass attacks unless they had the Cleave feat.

      My instinct would be to not give both. I don't know if that means I need to refresh it for all fighters, remove the Cleave feat, or reduce monsters to B/X numbers in my games. There's programming time I need to find for that. Super good catch!

  9. Most of the time encounters with hundreds of enemies are taking place in a confined space in the dungeon where only a few can attack at a time. But if it is a more open space and there are hordes of monsters against a small party of powerful PC's, I use the "cheat" method discussed here from a tournament Blackmoor game. https://odd74.proboards.com/thread/8509/get-yer-fighting-back-chainmail?page=2&scrollTo=130411

    Basically I'll throw one die for each tier of the character (veteran, hero, superhero, lord) and remove that many mooks per round. If there are lots of NPCs/followers/henchmen involved I'll turn the whole thing into a strategos style ratio by adding up HD and then roll on table T or whatever table is handy.