Mass combat has always been a tantalizing idea for storytellers, but it can be difficult in execution. Imagine two (or more) armies waging a lethal battle with all the magic at their disposal. It certainly makes for an epic backdrop to highlight the player’s actions. However, once the characters join as generals it often falls apart. Most game systems hinge on around three to six second combat rounds. This mechanically falls apart once you start using big armies. Long term spell effects or other class features that can be used endlessly spark fun conversations, but they make running mass battles hard.

Typically, storytellers will simply make the rest of the battle a cinematic backdrop and let the players do small scale or goal-orientated missions on the field. This works very well if the outcome of the battle is already predetermined, or you have multiple tables that can each hit some major objectives. Some game systems (like Legend of the Five Rings or Dungeons & Dragons) have books and chapters dedicated to running mass combat but the mechanics can be confusing. So here’s a GM tip for a quick way to run mass combat between system agnostic armies.

Let’s Crunch Numbers

Your first step is to write down the two “generals” and their army size. The generals could be a council of wizards on one side versus a single war veteran on the other. Let’s say they each have an army size of 100,000. Give each general an arbitrary leadership score based on your game system and gut feeling. In Dungeons & Dragons you might use their charisma modifiers. In Vampire: The Masquerade you might simply use their leadership score. Finally, determine general army advantages and simply increase the generals’ leadership score by a flat amount based on them. If one army has more magic they might get a +2. If another has better-trained soldiers, add +2 to that general’s score. Even army size can be a factor! Be as robust or as simple as you prefer.

Many characters and beings fight in an epic battle in Dungeons & Dragons
Wizards of the Coast

Next, you want to write down each main “player” on each side of the battlefield. This step is really fun and where this system shines. The “enemy” side gets a mini-hero to match each of the main armies and they can be as customized as you want or as simple as “battle wizard 1.” Of course the more flair you add, the better it is. You don’t need to have their full stats, just use their “leadership value” on your note sheet. It will be different than their generals. Everyone should have some variety because your players will have variety as well. If the characters have allies and enemies, this is a great spot to slide them in as well.

The war begins! At the start of the first turn, have all the listed characters (but not the generals) roll their leadership score versus the other. Again, your specific system determines how this is rolled, be it a simple D20 with a modifier, or a bucket full of D10s. Go through the whole list and record what each person rolled. You aren’t looking to total them up, just simply if they bested their “opponent.”

Each mini-victory adds a simple +1 or +2 modifier to their generals’ dice pool. Finally, using all the modifiers, have the two generals roll against each other. The winning side loses 5% of their army, and the losing side loses 10% of theirs, plus an extra 5% if the roll was particularly lopsided (i.e. one general rolled 30 and the other 5). This entire turn takes about one hour of in-game time for the party, and most armies are typically routed when they lose 40% of their troops.

All said, this is a very simple way to add some gamification to the battlefield. Once you roll the dice for the party, you can play matchmaker behind the screen as a GM. If you notice two people rolled the same dice, you might elect to have the two generals duel. Other fun tasks could include sneaking into the reserve or using clever party tricks to gain a battle edge. Run those tasks as you would normally in between these combat rounds. If they are successful, give more bonuses to the respective general.

By running mass combat in this way, the players can continue to be as creative and have real battlefield impact, but also feel like they are part of a larger machine in the entire army.

Originally published on September 19, 2019.

Rick Heinz is the author of The Seventh Age Series, Dread Adventures, and a storyteller with a focus on D&D For Kids, Wraith: The Oblivion, Eclipse Phase, and an overdose of LARPs. You can follow the game or urban fantasy related thingies on Twitter or Facebook or reach out for writing at