ItO Mass Combat in GLoG
Image: Adolph Metzner, "Battle of Peach Tree Creek, Georgia, July 20, 1864", 1864. Public domain source.
Mass Combat
I've never found a mass combat system that I actually like, which is too bad, because a big pitched battle is a good source of drama and a staple of fantasy fiction. The naïve approach of just rolling attacks and checking AC for each individual soldier leaves a lot to be desired, but if stray you to far into generating bespoke rules you risk spinning off into a whole separate game.
Chris McDowall semi-recently posted some notes on mass combat, and as usual I admire his ruthless minimalism. I figured I'll take stab at adapting that system to GLoG. I've even lifted the heading of this section from his post (With thanks! With thanks!). I imagine the rules that follow aren't far from many GM's first thoughts, but they're punchy, easy to reference, and push the scene towards crisis - the opposite of most mass combat rules...
Units
The basic unit of mass combat is the unit.
- Units have HP equal to their number of members divided by the Order of Magnitude of the battle. *(E.g. if units are measured in hundreds, then 600 pikefolk have 6 HP.) A unit can't have more than 10 HP.
- Units have an Armor value - 1 for light, 2 for medium, 3 for heavy
- Unit have a Damage Die based on the weapon they are mostly equipped with.
- Units have a Morale between 2 and 12. (E.g. 6 for an untrained militia, 8 for trained warriors, 10 for fanatics)
A unit can be led by a player character. If so, they take on the unit's armor and HP, but retain their usual Damage Die.
Initiative
If a unit attacks an unaware target, they and any allies aware of the plan go first. A unit led by a character rolls initiative as usual, but using Charisma. A unit with no leader goes after the enemy.
Taking Turns
On their turn, a unit can move a short distance and take an action.
When a unit attacks another unit, roll their Damage Die and deal the result as damage. If they attack a lone character, they roll a d12 instead. If a lone character attacks a unit, they deal only d4 damage.
Attack rolls might have Advantage (roll 2x and take the better) or Disadvantage (roll 2x and take the worse) based on fictional positioning - particularly terrain or having exactly the right gear for a situation.
Alternatively, a unit can brace themselves - all incoming attacks have disadvantage against them until their next turn.
A character leading a unit may spend their unit's action to use a feature or attempt a maneuver.
- Spell or features that deal damage within an area of effect deal d12 damage versus units.
- If an ability would separate a character from their unit, the unit hurries to catch up, consuming their move on their next turn.
Morale
If a unit loses more than half of it's HP / members, they test Morale. Roll 2d6 plus the Charisma bonus of their leader. If the result is less than their morale, they stick it out. Otherwise, they rout.
If a unit routs, any units in line of site must also test Morale.
For the GM
I defer to McDowall's advice for the most part when it comes to keeping the pace brisk and the scene engaging. Keep changing up the tactical situation every turn.
A few specific notes for GMing a massed host:
- Consider the enemies motivations in fighting the battle. If they lose their primary objective, they'll likely start fighting to make an orderly retreat.
- Specific units may (and perhaps should, if you have prep time) have novel tactics, but otherwise they push to envelop while maintaining their line.
- This system strongly favors units the aggressor and rewards getting multiple attacks against a single target. The enemy should strive to do the same.