Large(ish) battle mechanics

[xenophone]

I need some ideas on dealing with a larger scale battle. Something on the order of 30-40 npc/monsters/pc to each side.

The PCs are helping a small town defend against a mercenary invasion.

I think a conflict of this size is large enough that I don't want to resolve all the combats at the individual level, but small enough that I'd like to resolve combats where the PCs aren't directly involved with die rolls.

I was thinking I could put the less important monsters in groups of 5, and use one attack/dmg roll for the whole group, but that would greatly exacerbate the effects of a high or low roll.

 

[paradox42]

I've had to run a few battles like that during my campaigns. My preferred strategy is somewhat opposite of yours: I favor getting die rolls out of the non-PC fights completely, and just letting average numbers dictate what happens. In other words, assume every d20 roll comes up a 10, or 11 depending on your preference (but 10 is usually easier to add on the fly), and assume damage rolls come up average also. 1st-level Warriors or Commoners won't often have scaling feats like Power Attack to worry about, so most of the numbers become static. You can even work them out in advance if you like.

Of course, this becomes much easier if you usually make rolls behind the GM's screen, or run the game online and don't make all your rolls openly. That way when you say what happens, the players can't point to the number and say "Hey! Isn't that a hit?" or something.

 

[xenophone]

If you remove rolls, wouldn't every round between the same two opponents be the same; always a hit/miss and always x damage?

 

[Alan Shutko]

I'd probably pull out D&D's War Machine or AD&D's Battle System and fiddle with numbers until they felt right. Or, Cry Havoc was released for D20 and might fit.

 

[Tinner]

The Kingmaker AP has a decent set of rules for running engagements of this sort.
Basically, you break each similarly armed group of combatants into units, and each unit has it's own stat block.
Pretty quick and easy.

I've also run big fights like this right on the battlemat. I don't usually have enough minis, so I just use squares of paper to represent each model.
It's a lot more work, but the players really dig getting to cut loose with those huge battlefield-changing AOE spells, and watching swarms of goblins die under seige weapon fire.

 

[xenophone]

The Kingmaker AP has a decent set of rules for running engagements of this sort.
Basically, you break each similarly armed group of combatants into units, and each unit has it's own stat block.
Pretty quick and easy.

Which book of the Kingmaker AP are those rules in?

 

[Tinner]

Which book of the Kingmaker AP are those rules in?

Book 5 - War of the River Kings.
You can also get just the Mass Combat system with some tweaked and expanded rules from Jon Brazer Enterprises in their Book of the River Nations: Mass Combat (PFRPG) - Jon Brazer Enterprises | DriveThruRPG.com

 

[Wicht]

You might try Hank Woon's Warpath

 

[Steel_Wind]

I've used Cry Havoc (don't - way too bogged down) and Warpath (I wouldn't stiill too unwieldy and it's not well designed, frankly).

In all honesty, use the mass combat rules in 3.xx Miniature's Handbook. For this number of cobatants, the system will deal with this quite nicely.

There was a fair bit of negative feedback on ENWorld about those rules, but by and large, those complaints were from people who were expecting somethng WAY less detailed that the Mass Combat rules actually are. They work well; however, they are a little cumbersome (nowhere near as bad as Cry Havoc or Warpath though) and will take some getting used to for both the GM and players -- but once you've got it down, it moves along briskly while still preserving the RPG element to the game without devolving into a complete wargame.

I wouldn't use the Mass Combat rules in the Miniature's Handbook for a number of foes beyond 300-400 combatants max as it is too unwieldy. But for that size skirmish you have planned? It's pretty much perfect.

 

[xenophone]

Thanks folks! I'm going to give the Kingmaker rules a go first. It sounds like a simple solution, which is what I'm looking for.