This is not meant for a game where mass combat happens regularly, but rather a campaign where this might occur once or twice in the entire campaign.
This was posted on EN world in 2015... but I realize that forums crashes are a thing, and though "maybe this needs to be re-published?" Alas, I haven't managed to contact the author of the post to ask permission, but all credits are due to them.
By
ExploderWizard , from EN world:
Mass battles can be
a lot of fun and aren't that hard to run if you prepare for them. I am
developing a simple system for large scale conflicts which I will share here.
It requires a little GM prep work but not as much as running the entire affair
in the regular combat system.
The important stuff
will be taking place wherever the PCs happen to be. I got the idea for this
from the way I design adventure scenarios. A large battle is simply another
scenario. What is important to know is, what is going to happen without PC
interference. Once you have a good idea about how things will turn out if the
players decide to bug out or twiddle their thumbs, then you will be ready to
see how their actions influence outcomes.
LARGER SCALE
BATTLES
Have an idea of all
forces participating in the conflict both as allies and enemies of the PCs. The
statistics of these participants will help guide you making judgment
calls.
1) DIVIDE THE
BATTLEFIELD AREA INTO ZONES. There can be a handful or many depending on the
size of the conflict. Only use as many as you think that you will need. The PCs
will begin in one of these zones along with enemy forces that oppose them. This
may be a random placement or against specific enemies depending on the setup
and intelligence available to both forces.
Place allies and
other enemy forces in the remaining zones. Again base these starting forces
according to the information available to them. At this point all forces should
be deployed in zones. Draw a rough sketch map of the zones and note which
forces are in each one.
2) DETERMINE MATCH
UP COMPATIBILITY IN EACH ZONE. ( except the one the PCs are in) This is a rough
level compatibility test. Look at factors such as numbers/ratio, individual
prowess of combatants, special abilities, etc. This is where we determine if there
is enough of a mismatch to apply modifiers to the conflict. A positive modifier
means an edge for the PCS allies. A negative modifier means an edge for the PCs
enemies. For each zone determine the match-up modifier in a range of 0 to +/-
4.
This is where being
familiar with the participants stats is important. Only a severe advantage
should get a +/- 4 modifier such as being outnumbered 3 or 4 to 1, or a force
of regular men fighting half or more of their number of ogres. Remember special
abilities. If the entire enemy force is resistant or largely immune to the
other side's attacks (soldiers vs wererats) that would count as a huge
advantage.
This is also a good
time to assign modifiers for information the players may have that is shared
with allies or for good tactical deployment depending on the setup and how much
time there is to prepare.
3) FIGHT! Each round
determine the status of the battle happening in each zone the PCs are NOT in.
Roll 3d6 for each zone of battle applying the modifier for that zone. Use this
table to apply the outcome of a round:
3-4 (or less):
Allies in severe trouble- enemy gains 3 points
5-8: Allies in
trouble-enemy gains 2 points
9-10: Struggle
locked but stable- enemy gains 1 point
11-12: Struggle
locked but stable- allies gain 1 point
13-16: Enemies in
trouble- allies gain 2 points
17-18 (or more):
Enemies in severe trouble-allies gain 3 points
The first force in a
zone to reach 6 points wins the battle in their zone. Make a note of how the
battle in each zone is going. This way you know how the tide is swinging during
each round and roughly how long each zone will take to resolve.
4) DEGREES OF
VICTORY
Each zone will have
a victor. The cost of the victory is determined by the margin ratio:
6-0: clean sweep, almost no
casualties, enemy largely destroyed
6-1: easy victory,
5% casualties, enemy soundly defeated
6-2: victory, 10%
casualties, enemy defeated
6-3: tough victory,
30% casualties, enemy defeated
6-4: costly victory,
60% casualties, enemy barely defeated
6-5: pyrrhic
victory, 80% casualties, victorious unit broken
5) MOVEMENT BETWEEN
ZONES
A unit that achieves
victory in its zone can then reinforce friendly units in an adjacent zone. It
takes 1 round to move to an adjacent zone. A move across 2 zones would require
2 rounds, etc. All units save a broken unit can move to assist allies. The round
after joining an allied unit, the reinforcements add a +1 to +5 modifier to
their allies in the new zone depending on what shape they were in. A unit
moving to assist after a clean sweep victory would add +5 while a unit
following a costly victory would add only +1 for example.
All of this can be
determined in prep with notes of what is happening in each zone round by round.
Now there is a rough outline of how the battle will progress without PC
actions. As the players fight their part of the battle and move to help allies
in other zones you have a solid idea on what is happening in each place as the
PCs get there. The system isn't that difficult to use at the table if you would
prefer the flow of battle to be a surprise each round especially if you have
players help make the rolls.
This is still a work
in progress and meant to be a simple aide for mass combat in an rpg. There is
nowhere near enough detail to make an engaging war game out of it.
