War Week: A Harvest of Men

Back to some content.  This month’s blog carnival is all about war.  Appropriate; war or the threat of war makes a great plot element for just about any rpg, from fantasy to science fiction to espionage to superheroes.  It also happens to be something many RPGs don’t have very solid rules for.  They’re designed for conflicts on an individual scale, because the individual character is, from the player’s standpoint, what’s most important in most RPGs.  But how do you handle those scenarios in which your player characters find themselves caught up in actual battle — conscripted into an army, perhaps, or leading the king’s knights against the encroaching goblin hordes?

The combat rules are usually unsuited to handling large-scale conflicts.  The D&D Companion Set (and the Rules Cyclopedia) included the War Machine, a set of rules for mass conflicts, but many RPGs don’t.  One way of handling this is to break a battle into a series of squad-level encounters — maybe the PCs’ squad is sent to disable a ballista, or to sneak into the enemy camp in the night and assassinate an officer.  This does work very well when the characters are able to act as a relatively independent unit, and it works with both combat and noncombat encounters.  (Check out The Core Mechanic’s Skill Challenges of War series for one take on handling some common war events as skill challenges.)

But the average soldier on the field isn’t leading squads in commando raids.  If you’d like to find the general outcome of such a battle, chances are you’ll need some house rules (or GM fiat).  For this month’s carnival, I figured I’d walk through the creation of such a rule.  Welcome to War Week at A Butterfly Dreaming; I’ll be presenting a post every day through Saturday.  First I’ll be sketching out my system; after that, I have a bonus post about war in a fantasy setting waiting in the wings.

So, day 1.  With a house rule, I find it’s best to start by laying out the goals.  In this case, I want to keep things consistent with the feel of 4e, which means d20 checks against a target DC.  At the same time, I want it to contain some uncertainty, to reflect the back-and-forth nature of a battle.  I also want a continuum of success, rather than a simple success/failure dichotomy, so that even the winning side might be devastated by an intense battle.  I want something flexible enough to adapt to just about any battle — who knows when I’ll run a war in the ever-shifting terrain of Limbo?

I’m drawing some inspiration from the skill challenge:  multiple checks, tracking successes and failures.  Each success will indicate the players’ side seizing the advantage, at least momentarily.  Each failure will represent casualties or other setbacks.

Base DC

The base DC for a success is 10 plus the average level of the opposing force — not the entire opposing army, but the portion of it that’s being faced in battle.  If the invading orc horde is mostly level 3 but includes an elite worg-rider cavalry of level 6, then the base DC could be anywhere from 13 to 16, depending on whether the PCs’ army is facing all regulars, mostly regulars with some worg-rider reinforcements, mostly worg-riders, or almost exclusively worg-riders.

I’ve chosen 10 + level, rather than 10 + (level / 2), to increase granularity, under the assumption that many army-scale conflicts will involve masses of low-level creatures, with smaller numbers of higher-level elites scattered about.  Since the PCs’ rolls are based on level/2, this grants the enemies an advantage if the PCs are of equal level.  However, this is likeliest to happen at low levels, when the difference is only 1-3 DC.  This number is one of the things I’ll want to watch during playtesting; I might well end up dropping it back to (level / 2),  which also has the advantage of being a little easier to remember.

The target DC will be modified by a variety of factors, such as terrain and resources.

Base Dice Pool

The base dice pool depends on the severity of the fighting:

• Light skirmishing, 2d20 base.  Smaller groups coming into armed contact for relatively short periods.  These minor conflicts are rarely decisive.  Might include some scouts coming into conflict, a missile exchange or brief sortie during a siege, or a small cavalry unit harassing the infantry’s flank.
• Medium conflict, 4d20 base.  A conflict of larger forces, though still relatively brief.  Perhaps a single committed attack upon an enemy position.
• Heavy fighting, 6d20 base.  Similar to the above, but longer-term.  A series of attacks and counterattacks.
• Intense combat, 8d20 base.  Still more intense.  A day of almost non-stop fighting, with long periods of heavier battle interspersed with lighter skirmishing.  Likely to be a very bloody battle.
• Killing fields, 10d20 base.  The relentless savagery of all-out war.

Each PC will be able to modify the number of dice in his personal pool.  The GM might also roll, in this case for entire blocks of NPC troops.  More dice rolled means more potential successes — therefore, a bigger possible impact on the course of the war — but also more chances for failures, which bring injuries and setbacks.  The base dice pools are simply two twenty-sided dice per “level” of the fighting.

Tomorrow:  A look at some of those modifiers.

Related posts:

1. A Harvest of Men (III)
2. A Harvest of Men (II)
3. A Harvest of Men: In Play
4. Hacking Skill Challenges
5. Heroic Effort