Emerging Threats Unit: Basic Action Mechanics
I mentioned a few days ago on Twitter that I have a goal to, for the first part of 2014, write every couple weeks something about the Emerging Threats Unit, my action-investigation horror RPG. For those who don’t know what I’m talking about, the quick blurb is:
Ryan throws Delta Green, Unknown Armies, Pandemic, Fringe, the Twenty Palaces series, and the Laundry series into a blender to make a roleplaying game about the CDC’s secret paramilitary groups whose mandate is to preserve humanity from the physical and memetic plagues of the unnatural.
The Emerging Threats Unit is about saving towns and cities from the “contagion” of corrupt and inhuman influence, not every-week-is-about-saving-the-whole-world sort of story (which might mean there’s also a little Global Frequency in the mix). And it’s about the Centers for Disease Control, not the classic FBI/law enforcement type of organization, because I find that to be far scarier.
That sounded awesome to me when I started playing with this idea in 2010. It still fires me up today. But life frequently gets in the way of serious for-me design efforts, hence the idea of writing pieces of it publicly.
Basic Action Mechanics
ETU is about competent characters in dangerous situations, which was hard for me to model in Fate, as an Otherkind Dice experiment, and as an Apocalypse World hack — the three prior incarnations a few friends saw. At least, it was hard to model it in the way I really wanted to (though I learned something from trying it in those systems).
To that end, the game separates success on an objective with success at staying out of danger, and forces you to choose what’s more important. Whenever you act in a crisis or potential crisis situation, you gather up to three polyhedral dice — from d4s, d6s, or d8s, and rarely d10s. (How you determine what dice you gather comes from skills and other traits, which I’ll go into in a future post.) Then you split those dice into two pools: your action and your cover.
The GM tells you what he’s rolling for the threat, which is a single die between d4 and d10 — higher meaning the situation has escalated into something more threatening. ( You’ll see why shortly.) He says this as you’re assembling your pools, because ETU characters have a vague sense of how much peril they’re in in any given moment. Thus, you can choose traits and arrange your pool accordingly.
You roll both pools at the same time. From a UI standpoint, I imagine having one side of the character sheet say “ACTION” along the left side and “COVER” along the right, so you have a simple physical way to distinguish them built into the game’s design. (Or, you know, just remember which is which if you don’t want to use the character sheet method.)
For each pool, the highest die is your result. If you get doubles in your pool, that result increases by 1. If you chose to roll no dice in that pool, it’s 0. Pretty simple.
- Rolling a single d6 and getting a 3 means your result is 3.
- Rolling d6+d4 and getting a 4 & 2 means your result is 4.
- Rolling d6+d4 and getting a 3 & 3 means your result is 4 (due to doubles).
- Rolling a d6+d6 and getting a 6 & 6 means your result is 7 (due to doubles).
- Rolling a d6+d6+d4 and getting a 4, 1 & 1 means your result is 5 (due to the double 1s, even though the result die is 4).
- Rolling a d6+d6+d4 and getting a 1, 1 & 1 means your result is 2. (Triples don’t mean anything special. I think that’s too fiddly, but three dice does at least mean a better chance of doubles.)
The doubles mechanic potentially raises the ceiling of numbers ( if the dice are the same type), but more importantly is raises the floor of that nuber range; you can’t get a result of 1 if you roll 2 dice. [Now that I’ve written this, I think I’m going to call it “matches” rather than “doubles,” but I’ll leave it as-is for the post. Shows language process.]
Action results are rolled against a set, never-changing target. The results generate hits, which is a currency for how much effect your action has. (For example, getting two hits when shooting at a creature means that you can do damage and pin it down, or do double damage, or pin it down and do something else.) It depends on the skill/situation, which is something that I have revised over and over.
- Getting a 10+ means getting three hits
- Getting a 7-9 means getting two hits
- Getting a 4-6 means getting one hit
- Getting a 2-3 means a mitigating circumstance or sudden situation shift caused a weak success or failure, but it’s not due to incompetence
- Getting a 1 means failure because of the character’s ability, talent, mind, or body let her down
This never changes, in order to highlight that characters are competent. There’s no shift in target number, and rolling two (or even three) dice in action means there’s never a failure due to incompetence.
[I’m also thinking about dropping the 2-hit and 3-hit thresholds down by 1, to 6-8 and 9+ respectively. Playtesting will see if that’s too much. Maybe even drop 1-hit to 3-5, if I do that.]
Cover is where things get unpredictable. Once the player has rolled their dice for action and cover, the GM rolls for threat, and the difference is compared.
- Threat getting 4 or higher than the player’s cover means a major incident happens.
- Threat getting 1 to 3 higher means a minor incident happens.
- Threat tying cover means a near-incident happens.
- Threat getting lower than cover means no incident happens.
The incident mechanic is akin to AW-style hard moves, and is something I’m pretty flexible on. Major incidents kill NPCs, do grievous physical or psychological harm, destroy evidence, and so on. Minor incidents do less than that. Near-incidents push the story forward regarding the threat, and may be enough to increase the threat die for the next action or some other cosmetic effect that might become an issue after the fight — such as getting scratched by the creature as you drive it off with your flamethrower, only to discover that that’s how it procreates.
Cover doesn’t just apply to you, though. If you’re fighting off a beast near civilians, I can just as easily as the GM apply the incident to those characters…which will have its own repercussions as one of the ETU objectives is a complete cover-up of evidence, including mutiliated bodies. It is not a nice job, but it’s a necessary one.
Thus, the decision of how to split your three dice is key. How badly do you want to dish out hits against threats? How badly do you want to keep bad shit from happening? Which do you want more?
No matter what, though, the incident cannot negate the effects of an action. Otherwise, I might as well just make it a single-roll system.
Order of Operations
Players declare hits (which further reinforces character agency and competence), then the GM declare incidents. Mechanically, it’s simultaneous — if you kill a creature, but still score an incident, killing the creature isn’t going to save you from the incident. (But it will keep the creature from creating further incidents.
…is something I’ll cover later. I’m still playing with how I want to make information and advantages work in the game. I have some ideas, and they all involve slotting into the action system somehow.
This is the tip of the iceberg. The other dangerous actions take this action-cover form:
- Performing Unnatural Sciences (what the ETU calls magic and other strange activities) holds keeping your body and mind intact as cover, and keeping your experiment (a.k.a. spell) under control as action.
- Withstand Trauma and Withstand Horror used to be cover-only skills, and I’m using the damage system I wrote up 2012. I’m playing with what to do about them.
Investigation and Discovery situations use a completely different paradigm, one that reflects what I find fascinating in GUMSHOE as well as what I don’t care for it in. But, that’s for a later post, because that’s the crux of the “investigation” part of “action-investigation horror game.”
Spells are what people really dig about this concept, when I talk to them about it. But rather than gush, that also gets to be its own later post.
My thoughts on what it means to GM this game are complex, and…well, you’ll see.
And, of course, much more. This is my next white whale, after all.
 I originally did this as selecting red action dice and blue cover dice, but that turned into a slowdown as people had to process what die types they could choose from and then figure out how to divide them up between red and blue without accidentally grabbing incorrect dice. The character sheet concept came from the ETU playtest I ran for Josh Roby and others.
 Well, maybe. Maybe the creature isn’t permanently dead or whatever. But the point stands enough.
 One that’ll see some smaller games produced in the meantime, because I want to get some of those out into the world rather than have them wait on another large (for me) game.