Zoned “mapless” combat for GURPS

I’m blog-stalking +Peter V. Dell’Orto these days. You should too. He’s penned a few posts on mapless combat for GURPS that got me thinking, again, of borrowing concepts from other games. In this case, the concept of Zones from Fate.

Zones are a nice, abstract way of thinking about who’s where in a narrative game. You can fight someone if they’re in your zone, you can shoot someone at a penalty across zones (perhaps; depends). But by and large the only purpose of the combat zones – and it’s a good  purpose – is to give a general narrative guideline of who’s where. Character A can act on NPCs 1 and 2. Characters B, C, and D are dogpiling Boss 3. For A to act on Boss 3, it’s more difficult.

GURPS has this too


What you say? Yes, it’s true. GURPS Action 2: Exploits, also known as the gift that keeps on giving, introduces a Range Band Table on p. 31 (in boxed text). Each band is -4 farther away than the prior band.

One of the nice underlying mathematical truths about the range bands (or just the Size and Speed Range table in general) is the fact that each step is a constant multiple of the one preceding it. This is just the nature of logarithmic tables, and for GURPS, the scale is each six steps are a factor of 10, or each step is x1.47 the one preceding it. This is usefully rounded to x1.5, but really the way GURPS does it is to have short memorizable progressions. GURPS’ favorites seem to be 1-3-10, 1-2-5-10, and the SSR progression, 1-1.5-2-3-5-7-10.

We’ll return to this in a moment.

Battles are Vector, not Scalar


One of the bits about the range bands and mapless combat is that everything is relative to everything else. If you have three groups of three people fighting (say three foolishly overconfident PCs fighting two monsters each, in separate groups), then while each group of three is in contact distance with each other, they could each be at different range bands from each other.

And just because two groups are at (say) medium range from one party, they might be at short range to each other.

So, this sort of thing is vector (magnitude and direction matter), not scalar (only magnitude).

Yummy pi, which equals 3 in GURPS


Again with the math. Always with the math . . . but if we picture a range band as a circle (or sphere, but let’s do 2D for now), then the circumference of the band is roughly 6x the distance from the center. This is exactly true if we treat the perimeter of the band as a ring of hexes (thus the phrase I’ve seen: In GURPS, pi is equal to 3).

That means that if it takes one action of arbitrary time to close from your current range band to contact distance, you can take three actions to go around contact distance at constant radius. It also means that (conveniently), you can subdivide any band into six chunks, each of which is one band smaller. It also means that much like tactical combat, you’re in a hexagonal reference system.

That means rescaling the bands from action, though. A very coarse progression would be 1-3-10 – and starting with 3, because you can, with a committed attack and a Reach 1 weapon, or a Step and Reach 2 weapon, easily fight anyone closer than that.

Bands and Progressions


So if we want to define “in melee combat distance” as 0-3 yards, for no penalty, we’ll wind up with a progression that looks like:

0-3 yds: Contact Distance (0)
4-10 yds: Close Range (-3)
11-30 yds: Short Range (-6)
31-100 yds: Medium Range (-9)
101-300 yds: Long Range (-12)
301-1000 yds: Extreme Range (-15)
1001-3000 yds: Maximum Range (-18)
3001+ yds: Beyond Visual Range (-21)

Now, this chart is human-centric, earth centric, and ground-level centric. But there’s utility here. Consider:

Mos pistol fights are in the “Close” range band. But shooting to short range is possible and you can with care and time hit at medium range. That’s 1 and 2 bands. If you consider SMGs, typical engagement distance is closer to 30yds, but 100 yds is a bit harder and 300yds is about all you’re going to want to shoot (despite both pistols and SMGs having true maximum ranges in the Maximum Range band). Rifles? 100yds is pretty routine, 300yds is used for qualification, and 1000yds starts to be the stuff of legend, with shots in the middle of the Extreme Range band being routine for the best shots. This would negate the influence of Acc, though.

One might simplify that you can extend your range by one band with an aim action, and two with two, and farther is a no-no. Or you can use the regular Acc and Aim sequences.

Likewise, you can shoot from A to O or A to B at the standard -3 per band penalty, while A to C is an additional -1 and A to D is an additional -2.

Note that it doesn’t matter what the A-O band is in the above. It could easily be A-O is Close Range as Extreme Range. As long as A, B, C, and D are in the same band, the penalties apply just as well.

Note that if you don’t want to ditch the Action range band sizes, the above penalties still work. A-B is no longer simply a range band down, but it’s still at no extra penalty, A-C is -1, and A-D is still -2.

Closing and Extending Distance

The other bit about bands that players will want to know is how long it takes to transition between them. Given the distances involved, and “typical” PC move rates in the 4-7 yards per second range, you wind up with something like this:

• It takes about a Move action to get from Close (call it 7 yds) to Contact (around 2 yds). But it could be as little as a Step, or it could be two actions.
• It takes about 2-3 Move actions (8-21 yds of distance) to close from Short to Close range.
• And so on – it should take 3x more moves for each band.

What I want to do is think about the smallest ranges – Contact and Close – and then we can use the 1-3-10 progression in time to extend that.

But basically, the rule is that to move between range bands, you need to spend some time “in transition.” When you’re in transition, you’re still in your current band.

Closing distances (going from a higher band to a shorter one) requires one unopposed transition. Extending it requires three.

Unopposed transition? Yeah. Your foe can keep you at bay by moving herself, too.

So, Bob wants to attack Kara. He’s at Close range, and wants to move to Contact. He takes a Move, and it in Transition. Kara can decline the engagement by taking a Move herself, which negates the transition and sets him back to Close Range. Or she can accept it and not move, doing something else.

Close to Contact: this is a bit of a special case. A fighter in Transition can Attack into Contact from Close Range. Likewise the defender can Attack into Contact if her target is in Transition from Close Range too.

Escape from Contact: It only takes one Move to get from Contact distance to Close Range. Your foe, of course, can use the above to engage with you, and if he wants to Move and Attack (forgoing defenses) he can do it on one turn. This does assume the endless featureless plain, which is a bad assumption. It’s plausible to force some sort of skill test – an Evade action or something – to simulate getting out of more constrained surroundings. Or even disallowing extending the range at all past a certain band.

Boring Boring Boring – It’s about time

If you have characters at all ranges, then you can easily get situations where, for example, it takes your sniper, kickin’ out there at 500 yds from the main battle, 100 turns to get to contact distance. It will take about 70 turns to shorten to Long. Table below.

The point here is to allow either the range bands from Action, or the more hex-friendly ones here, as a half-step between mapped combat and mapless combat. Some degree of relative groupings of combatants. Some notion of how far and how long it takes to get from place to place. And something that can be drawn out on a piece of paper with a few largish hexes – one that allows placing minis or markers in zones to allow rough situational awareness.