Friday, March 10, 2017

Lethality in the Alternity Game

A little change of pace this time: I'm going to talk about some of the mechanics I'm working on for our new Alternity Science Fiction Roleplaying Game. We released a beta version of our Quickstart Guide, and we've been thinking hard about just how deadly deadly ought to be. (By the way, you can download the Quickstart Guide for free here:

Lethality in Alternity

Since releasing the Beta test rules for the Quickstart Guide, we've seen some good discussion in a few different forums about the rules we’d created. We’re still looking for feedback on our game and we hope to incorporate some “lessons learned” into the Core Rules as we develop them, so we think it’s a *good* thing to see some of our assumptions challenged. One of those assumptions is, naturally, just how deadly guns ought to be to player characters.

If you haven’t looked at the Alternity Quickstart Guide, most of this probably won’t make much sense: This is for folks who are wondering what we did and why.

First Assumption: Let me start with one key assumption you might not agree with: Heroes are special. We’re not trying to model real-world gun lethality for the PCs. We’re trying to model action-movie, cinematic lethality. Heroes in action movies rarely drop from one shot… but mooks and civilians usually do. The typical hero’s durability track might have 6 to 10 boxes, but a mook or noncombatant might have only 2 boxes. And those boxes might have lower values than the hero’s wound boxes. For example, Dr. Ayers in the Magellan adventure has two boxes: 1-9, and 10+. That’s much more vulnerable than we want heroes to be, but that’s okay—she’s not the star of the show.

Second Assumption: Average hits produce injuries; it takes Excellent or Stellar hits to generate wounds that might be instantly life-threatening. So damage ranges for Average hits shouldn’t reach values that might punch out a hero.

So, with those two basic assumptions out of the way, let’s look at the real interaction people are curious about: one hero shoots another hero, or a NPC who’s supposed to be just as tough as a hero. (That isn’t a typical foe in our Alternity action movie, BTW—most mooks should be a lot more brittle.) So what are the odds of one-shotting the near-peer foe?

Lucky 13

The key number here is 13. If a weapon hit gets into the 13+ damage range, you’re in the wound band right before the punch-out at 16+. An unarmored character with one wound box at 13-15 is at risk of instant punch-out from any weapon that can deal 13 damage, because a Stellar hit automatically deals 2 boxes of damage. The first box of damage marks off the 13-15 wound box, the second ticks off the 16+, the bad guy drops. Assuming you get a Stellar success in the first place, that means:

Plasma Pistol (2d8) = 15% chance for one-shot
Heavy Pistol (1d8+6) = 25% chance for one-shot
Battle Rifle (1d8+8) = 50% chance for one-shot
Sniper Rifle (1d8+10) = 75% chance for one-shot

Remember, those are the same chances that Badguy Miniboss punches *your* ticket if he gets a Stellar success on your character. Good thing you’ve got a hero point or two just in case, right?

The conspicuous absences from that short table above are the weapons that max out at 12 or less damage: the light pistol (1d6+5), the laser pistol (1d6+6), the combat knife (1d4+5), etc. They can’t one-shot an “Evil PC,” but I’ll note again that they can certainly one-shot Dr. Ayers or the typical mook—because two boxes of damage kills a mook, and Stellar hits produce two boxes of damage. Whether those light weapons should be able to one-shot your PC is a fair question; maybe we should nudge them toward that magic 13 as a maximum damage roll, although it might make the heavier weapons too deadly for our taste.

Some weapons—shotguns and blast cannons, for example—routinely produce 2 wound boxes under the right circumstances. For a Stellar hit, that increases to 3 wound boxes… which means that suddenly the magic number of 13 is actually a magic number of 10 for characters with one wound box at the 10-12 band. A Stellar hit from a shotgun at close range has a 50% chance to one-shot because of that. And *any* close-range hit from a shotgun punches out a mook or noncombatant.

In Summary

Overall, how close did we get on the lethality? Well, you can be the judge of that. I’m reasonably happy with the chances we’ve described above: Some hero in the party receives a Stellar hit from the bad guys in just about every gunfight, and we don’t want a good roll from the GM to be an automatic death warrant. And hits against non-heroes tend to punch ‘em out on any Excellent success with a halfway decent damage roll, which also seems good to me.

Closing Thoughts

There are two lessons I learned from writing all this down. First, we probably ought to look a little closer at heroes with 2 boxes in the 13-15 wound band. That’s pretty good, and maybe we were a little generous with that. Second, the laser pistol and light pistol might want a wee bit of a boost to threaten a 13 on a max damage roll. But those are pretty straightforward adjustments as we continue to develop the Alternity game.

(Hmm, weirdly enough the right way to boost the light pistol might be to use a damage range of something like 1d10+3. That d10 looks wrong as a damage expression for a small weapon, but what we’d really be saying is that your .25 cal pistol only has a 10% chance of one-shotting as compared to the 25% chance for a heavy pistol. Have to think more on that!)

Thanks for helping us to dig in on our new rules set—and thanks for caring enough to share what you think about Alternity!


  1. It might be a bit off-the-wall, but have you tried doing away with the hit points/wound checkboxes altogether? The system would look very similar to what you already have: serious wounds would still give immediate penalties, but you can take any number of them - there are no checkboxes. The trick is that you need to take a Resilience check each time you receive a new wound. The difficulty depends on the wound severity and wound penalties definitely apply, in fact all wound levels should give a penalty on these rolls! Failure means you pass out; failure by a lot (or on a second roll) means you die. If you want some added realism, the first wound you take in a fight should have the difficulty bumped up a couple of steps.

    After the battle, each wound must be recovered from separately; bad failures here can make the wound worse - a mortal wound getting worse means death. If you want some additional tension, add in some permanent penalties for very serious wounds healed without extra-special treatment rolls...

    Only one RPG system* I have come across uses a system like this, but it gives a "feel" and game atmosphere that those who've played it find quite special. I commend it to you :-)

    *: HârnMaster, FWIW.

    1. I should have said - the advantage I see with this relative to your original question is that one-shot kills with this system are possible at any level, but very unlikely at lower wound levels. Balanced well, the light pistol can have a very low KO chance but still have some effectiveness - especially against those with low Resilience. Big weapons, meanwhile, can have a much higher chance of a KO, but not a certainty.