View Full Version : Mass Combat System (Pathfinder/3.5) (PEACH?

2016-04-14, 07:02 PM
Hello again to the forum I have never posted a thread in as far as I remember. I have been thinking about designing a mass combat system based off of D&D and Pathfinder. I don't have an entire system worked up but I do want to share some of the basics just to see peoples reactions. I might have made it way to complicated and clunky to play out.

Base Attack Allocation is the square root of the troop count rounded down.
Shock Save is the troop's base Fort save + the troop's Con bonus + the commander's Wis bonus.
Shock is used to prevent casualties and take aggressive actions.
Maneuver Save is the troop's base Reflex save + the troop's Dex bonus + the commander's Int bonus.
Maneuver is used for positioning related abilities and is related to fast reactions.
Moral Save is the troop's base Will save + the troop's Str bonus + the commander's Cha bonus.
Moral is used to take risks and to keep the troops in combat.
AC is the AC of the troops.
Unit HP is the troops multiplied by the number of troops in the unit.
Attacks are taken from the regular stats of the monster. Multiple attacks like the two claws of a dragon only count for half the number of attacks. So a creature with claw attacks would only have one claw attack on the unit sheet, but an Aboleth with 4 tentacle attacks in personal scale would only have 2 attacks in mass combat.
Therefore a large dragon would have a Bite, a Claw, a Wing attack and a Tail Slap.
Iterative attacks are used as normal as well as two handed weapons. So a squad of two weapon rangers would have 2 attacks in melee and 1 with their bow.
Other abilities will likely be carried over at some point. As of yet I do not know how to implement them.

Combat resolution between units is simultaneous unless some ability allows one unit to strike before another.
Each unit in a skirmish rolls each of their attacks against the opponents armor class.
If an attack roll hits the enemy's AC the attacking unit inflicts a number of hits equal to their BAA.
If the roll exceeds the AC for each point above the roll increase the number of hits by 10% capping at an increase of 100%.
Do the opposite if the roll doesn't beat the armor class, to a minimum of 0 hits by AC-10. Remember that all numbers round down.
So if a unit of 20 elven archers with a BAA of 4 rolls a 16 against a band of orcs with AC 13 the elves will score 5 hits (4x1.3=5.2 rounded down)
To calculate the damage of the attack multiply the attacks damage by the number of hits. Then take the square root of the number of damage dice rolled rounded down, roll that many dice and take the average for the rest of the dice.
So the elves listed above made 5 hits with their long bows which would deal 2d8(Root of 5) + 13 (4.5x3) damage. Let us call this 23 points of damage.
Subtract the damage from the defending units hitpoints.
So in the case of the elves attacking 20 orcish warriors the Orcish band would have 120/120 hit points before the attack and 97/120 afterwards.
To calculate casualties find the number of troops the damage taken by the defender could kill.
So in the case of the aforementioned Orcs this would be 3 potential casualties.
Roll a Shock save against a DC equal to 10 + (Potential Casualties/All troops) + (2 per Casualty save since last death)
So the Orcs would roll against a DC of 13.
The number of casualties is calculated similarly to the number of hits. So for each point you beat the save DC by reduce the number of casualties by 10%. Remember that you round numbers down so if you roll over the Save DC the number of casualties is always decreased by at least 1.
Note if a unit is completely out of HP then the unit has all been killed and thus you do not need to check for casualties.
So in the case that the Orcs roll a lucky 20 on their Shock save they will take no casualties because (3x.3=.9, round down to 0).
The next turn the Elves attack again getting unlucky and score only 2 hits dealing 8 damage.
The Orcs are now at 89/120 HP with 5 potential casualties and 1 check without casualties.
So the Orcs must check against a DC 17 save. Unfortunately they get unlucky and roll only a 15 on their save. So their unit takes all 5 casualties.
Whenever casualties are taken reduce the maximum HP of the unit and recalculate the BAA.
So the band of Orcs who started with 20 members, 120/120 HP and a BAA of 4 after two rounds fire from the Elven archers now have 15 members, are at 89/90 hp and have a BAA of 3.
At some point I might add a moral damage system which would function similarly to the Casualty system.

Troop Type Commander
Troop Count BAA
AC Unit HP Troop HP
Sho Man Mor
Str Con Dex (From Unit)
Int Wis Cha (From Commander, in examples Unit is Commander)
Attack Bonus Damage
Special Abilities
Troop Elven Warrior 2 Commander -
Troop Count 20 BAA 4
AC 15 Unit HP 11 Troop HP 220
Sho +3 Man +3 Mor -1
Str 11 Con 11 Dex 14
Int 12 Wis 8 Cha 9
Rapier Bonus +4 Damage 1d6
Longbow Bonus +4 Damage 1d8
Special Abilities Weapon Finesse
Still to come.

2016-04-14, 08:05 PM
HAve you checked out the existing Miniatures Handbook? If so, what doesn't work for you?

(Also consider, are you doing this to play army vs army as players, or to make the background of your campaign more granular and realistic as a DM? IF it's the second, you can simplify and handwave A LOT.)

2016-04-14, 08:42 PM
No I haven't read the Miniatures handbook. Does it have good rules? Truthfully I thought the miniatures handbook was a weird sourcebook sized rulebook for the D&D miniatures line with tie in rules for the actual game.

On the question of why I want to make a mass combat system, really it is because I was thinking about it and have never really seen a system in another book which I thought was really good and what I have so far is at least decent. Relatively easy to convert humanoids. Seems to have at least some crunchiness. I don't really know what it would be for. Probably intended for some in game use.

I might try what I have so far with large armies. And work up a unit of dragons to throw against an army.

2016-04-14, 09:53 PM
Pathfinder also has mass combat rules for the type of thing you seem to be after. They were republished in ultimate campaign after they appeared in kingmaker, and I believe they're on the SRD

2016-04-18, 09:13 PM
Here are the mass combat rules for Pathfinder: http://www.d20pfsrd.com/gamemastering/other-rules/mass-combat

They can also be found in the Ultimate Campaign book.


Final Hyena
2016-04-19, 12:25 PM
How do your rules handle a legion being fireballed?