Tuesday, March 14, 2017

Getting Things Done In Demon City

More Demon City--donate to the Patreon here. I think I'm doing some new Druid spells for 5e tomorrow.

Demon City will be pretty rules-lite, but I've given some thought to how the rules it does have will be presented.

The rules themselves will be on the left-hand pages of the book, notes on the implications of these rules (asterisked here) will be presented on the facing pages.

As in most tabletop RPGs, Demon City proceeds according to a simple scheme: the Host describes the situation(s) the characters are in, the other players say what their respective characters try to do. When failure might have interesting consequences*, the rules and dice get involved.**

Simple example: Marty might come home late and drunkenly fumble at his apartment door lock before getting the key in, maybe even dropping the keyring in the process. But eventually he'll get it open, so there's no need to roll dice...

...unless (whether or not Marty knows it) Marty's brother is lying on the other side of the door about to bleed out. That's when you'll want to roll some dice.

EDIT: These rules revised Thursday March 23rd

EDIT: And April 29th

EDIT: And May 27th in Helvetica

EDIT: And May 30th in Helvetica

Task Resolution

Basically, for most tasks, the player rolls a d10 vs a Target number or the Host rolls a d10 and if the player beats the target number or gets a higher roll than the Host, the task gets done, if not it doesn't and some consequence of failure ensue.

There are some hitches, though:

-There are many cases where the sides roll multiple d10s. Their official roll for the purposes of deciding the contest is whichever of their rolls is highest. So if you roll a 6 and an 8, your "roll" is 8.

-All character stats are ranked from 0-9 (or possibly more, with no maximum, if the supernatural is involved), high numbers are good. If two characters (player's characters or a player's character and an NPC) are competing at a task (say, in a footrace) then whichever has the higher stat gets to roll an extra die. This extra d10 is called the Skill Die.

-Likewise, for tasks where characters do not directly compete (Marty trying to pick an electronic lock, for instance) all tasks are ranked in difficulty from 0-9 (or possibly more, with no maximum, if the supernatural is involved). If the stat number is higher than the Target number, the player gets to roll an extra die and use the better of their two rolls (the "Skill Die").

-Having the Host roll even for the difficulty of dealing with inanimate objects (opening a lock on time, locating a file, climbing a wall) tends to personify the environment--the electronic lock is programmed by someone and Marty's attempts to crack it are against the skill and effort put in by that programmer. However, when there is no way to imagine any animate force actively resisting--like in the example of Marty drunkenly scrabbling at his own lock with his own key--the Host can just assign a static difficulty number to be rolled over (player must roll over a 3, for instance). Recommendations of when to do this and what the numbers should be come later, but just to nail down the basic system, know that the the opposed roll is usually preferred when it's a toss up.

-If a task targets someone who is distracted (pickpocketing someone who is watching a car crash happen, for instance) or doesn't know they're there the perpetrator also gets an extra die (the Distraction Die).

-If a task has some other outside factor introduced that makes it more likely one side will win (if someone has a head-start in the footrace, for example) then that side gets another d10. This extra die is called the Situation Die. You can have up to two Situation Dice representing distinct advantages (ie two advantages that would, individually, still be advantages without the benefit of the other advantage--like a headstart in the footrace plus your opponent is running over uneven ground).

-Generally, external problems which make the task harder (like Marty being drunk while trying to open the door) are worked into the difficulty number of a task, but if there is some reason they can't be or haven't been already, the Host may subtract up to two Lost Dice (down to a minumum of one rolled die) to account for problems.

-In the case of a tie (around 10% of the time, depending how many dice are involved) the Host must think fast: the situation becomes more complex, but not in a way that immediately decides the contest. The task can be attempted again in the new situation. For example: if Marty and the Host tie as he's trying to open his door then the Host might declare that blood has begun to seep out from under the door and one of Marty's passing neighbors has noticed.

-If a character rolls a 10 and wins (ie not a tie), they have a critical success, if their best roll is a 1, they fumble. If both sides' best roll is a 1 when two characters are competing, the situation gets worse for both sides. (Most people reading know what "crit" and "fumble" mean so while the final text of Demon City will give some examples, that's all you need to know for now.)

-This all gets more complicated in situations when different characters are trying to do different things that all affect each other at the same time. Combat is the most common situation like this but it could also apply to, say, trying to fix a radio antenna before a metastasizing Crysoloth destroys the building it's in. Like most games, Demon City has special rules for that...

Action Rounds: Slow Motion and Clashes

Like in most RPGs, special rules are used to resolve action. A footrace isn't "action" as defined here because the competitors usually aren't interfering with each other. A car chase can be, though, because cars can cut each other off, knock each other off the road, etc. And combat is always action.

I'm going to describe combat using some D&D terms here because this is a D&D blog so you probably get it--and it'll be faster than describing it from the ground up the way it'd be written in the final book. Basically, there's no initiative but there are rounds. Action's generally going to be over in fewer rounds than D&D, but each round takes a little longer. If it's necessary to know, rounds take about 6 seconds of activity--but a Demon City round might actually represent a narrower or longer slice of time, because essentially a Demon City round only establishes what the next action in a conflict (or set of conflicts) is.

Think of it like a comic-book panel or a shot in a movie--the Round exists to establish what happens in that panel.

This action system is based on "Clashes"--the most important difference between a Clash and the combat in a D&D round is only one party in a fight can succeed at a time. You shoot or are shot, punch or get punched, etc. If you're shot, you don't get to shoot back until the next round (assuming you live).

This is also one of those systems where everyone announces what they're going to do before the first person actually starts to do it. This is slightly less intuitive than resolving an action as soon as it's announced (the D&D way), but I think there's a payoff in that it more closely reflects the fast-but-tense way combat works in horror and crime fiction.

When the Host announces you've entered Action Rounds:

Slow Motion Phase

1-Whatever entity involved has the lowest Agility (Ties are decided randomly and stay that way for the session) announces what they plan to do. This can't be an if-then, they gotta decide. (Actions can normally only target one foe at a time--exceptions will be noted when we get around to specific abilities and weapons.)

The Host can begin to describe everyone noticing this slowpoke getting ready to do whatever they're going to do--as if everyone is watching slow motion.

One piece of advice: write down player characters' names in ascending order of Agility, so you can do this the same every time. Resolve ties between players at the beginning of the game to make life simple.

2-Figure out how many dice this character has for their action:
  • As with simple Tasks, a character with a higher Stat than the Stat they're targeting gets to roll an extra die--the Skill Die. Most close combat actions in combat (kicking, punching, knifing) rely on Agility or Toughness, whatever is higher, or Hand To Hand if they have it and target the foe's Agility or, if they have it, the foe's Hand-to-Hand combat skill. All shooting relies on Agility (or Firearms or Exotic Weapons if applicable) and targets Agility. Once a foe is grabbed, actions generally target a foe's Toughness. 
  • If you are only actively defending in a round, you get an extra die, the Defense Die.
  • Anyone with a situational advantage (high ground, etc) over whoever they're directly facing off against also gets an extra die (Situation Die).****
  • If you successfully used a defensive action to dodge, or block, parry an attack in the previous round, you get a Situation Die in the round after, as you've improved your position.
  • Another Situation Die is also available to anyone if the character has a second distinct situational advantage on top of the first one. Like their target is both tripping and is handcuffed. This die is also used if someone is attacking (or parrying) with a weapon that is better in the specific situation than the one their opponent is attacking or parrying with. For example, if two characters are fighting under a twin bed, the combatant attacking with a knife or claws will get a Situation Die against a target using a longsword (which needs more room to maneuver), but in most situations it'd be the other way around because the sword has better reach. And all of them would have a Situation Die over an unarmed combatant. This is the main way weapons are differentiated in Demon City (and in horror films)--by the situation in which they are most useful. 
  • Nobody in a Clash can get more than 2 Situation dice.
  • There's a bonus for teaming up on someone: The second and subsequent characters to target a given foe in the same clash get an extra d10, the Distraction Die. The first character to attack that foe doesn't.
  • Anyone who has taken at least one injury during the fight loses a single die (the Lost Die for Injury)--down to a minimum of one die. 
  • Other external difficulties in the situation not otherwise accounted for (by, for example, someone directly opposed already having gained a Situation Die) can be accounted for by Miscellaneous Lost Dice.
  • Nobody able to act in a Clash can lose more than 2 Miscellaneous Lost Dice this way or go below a minimum of one die.
  • So the maximum dice anyone could roll would be 5: A d10 to start + 1 Distraction Die or Defense Die + 1  Skill Die + 2 Situation Dice + no Lost Dice.
3. If nobody wants to in any way interfere with that slowest character's action, they can go take the action, rolling if necessary.

4-Second-least Agile creature announces next and collects dice for their action (and maybe rolls), then the third-least Agile, etc. until they're all announced.

The Clash

5-Everyone performing a contested action now collects dice and rolls--this group of competing attempts to do things first is called a Clash. Everybody involved in a Clash rolls d10s at once, as above under Task Resolution.

It's possible for a fight with characters squaring off against multiple opponents to actually made up of multiple clashes, so long as none of the personnel trying to interfere with each other overlap. So Alfred and Bebe could be fighting Ceelo and Didi and Eve could be fighting Fifi and that would be two clashes. If, however, Fifi was trying to pickpocket Alfred it would all be one Clash.

Exception: Competing drivers/pilots in a chase always count as being in a separate Clash with each other, even though each driver's actions could theoretically influence everyone in either car/boat/plane etc. So: each round, unless there's a tie, one or the other driver gets to pull a maneuver each round (or they tie).

6-Whoever rolls highest in a Clash takes their action

If a successful action involves damaging another character:
  • With most weapons, the attacker rolls damage as follows: They take a number of d10s equal to the target's Base Toughness, roll and take the lowest, and the target subtracts that number from their Current Toughness. At Current Toughness -1 or more they are out of the fight and roll on the Injury table (that'll be in a later entry). So if you have Base and Current Toughness 3, someone shooting you would roll 3d10, take the lowest, and subtract that from 3. If their Toughness is 0 you still roll one die.*****
  • Some few weapons (supernatural abilities, high explosives at close range) do Massive Damage. In this case you roll one die for each point of the attacker's stat and take the highest.
  • Kevlar and other protection raises your Base Toughness for these purposes.
If a tie for first occurs, then one of two things happens:

-If it's a tie between two characters on the same side (ie, two PCs who are getting along or two hostile NPCs with the same goal locally) then the winner is decided randomly--flipping a coin or rolling lone d10s will do it.

-If it's a tie between characters on opposing sides the situation stays mostly the same as it was before the Clash and nobody's action takes, but the Host changes something in the situation that affects everyone in the Clash, like: the roof could begin to collapse from the weight of the combatants

7-If there is more than one Clash involved in the Round (i.e. there's another, non-overlapping group of people tussling as-well, or drivers/pilots in a chase), it is resolved as in 5, with the highest roller acting.

8- Any action not prevented by the winning actions and which doesn't involve anyone else happens.

Anyone only moving from one place to another (including driving, flying a plane, etc) does so long as nothing stops them.

If, say, Ann successfully kicks Bill and Cassie just wants to pick up her gun she can do that. If, on the other hand, she wants to help Ann up off the ground, we have to wait until the next Clash to see if Cassie manages to do that.  

9-Anyone who is present and who needs to roll to get up from being Injured or stop a Panic rolls.

10-Nothing else happens. (Often only one thing happens per round.) . If characters are still involved in Action after all that, start over at 1 above.



1-Slowest character announces action
2-They collect dice if necessary
3-If no-one wants to interfere, they take their action, rolling if necessary
4-Other characters do 1-3 in reverse Agility order
5-Everyone involved in a clash rolls
6-High roller of one Clash acts
7-Any other Clashes (including competing drivers/pilots in a chase) resolved as in 6
8-Actions not involving others happen.
9-Injury/Panic rolls
10-Nothing else happens. Start over at 1

Possible Dice:
Skill Die (Attacker Stat>Targeted Stat)
Defense Die (For only defending)
Max 2 Situation Dice (for misc advantages incl. superior weapon & successful defense last round)
Distraction Die (2nd and subsequent attackers in the same clash)
Lost Dice for Injuries
Miscellaneous Lost Dice (max 2)

Notes I'd put on the facing page:

*Note that failure doesn't have to have predictably more interesting consequences than success--just consequences that are also interesting.

**As in many other games, dice also occasionally get involved when the Host (or even a player) just thinks it would be interesting or more fair to introduce a random element into a part of the game they normally control. For example if a player steals the first car they see, the Host might randomly roll to see what kind of car it is.

***It's possible more than one Skill die gets handed out to opposing sides this way if a fight is sufficiently complicated. For example:


If Alfie (Firearms: 9) is trying to shoot Betty (Agility: 5, Firearms: 5), who is trying to shoot CeCe (Alfie's friend, trying to flee with Agility 1)), both shooters have a higher stat than their targets, and Alfie and Betty will both get a Skill Die despite being on opposite sides and despite Alfie being better at shooting than Betty. CeCe will also get a Defense Die (only running away).

So if he and Betty try to shoot each other, he gets a Skill Die and she doesn't. If Betty targets CeCe, both Alfie and Betty get a Skill Die but Alfie gets a Distraction Die too, keeping him at least one up on Betty, all other things being equal.

****The value of this extra die means that combat in Demon City will involve a lot of players and Hosts discussing what does and does not constitute a situational advantage. This is good. This is what the players should be doing: talking about the fictional situation as if it were real so everyone is imagining the same events as much as possible and making interesting decisions about how to use the situation. More than one of the entities involved in the Clash can get this Situation die.

*****Humans generally have a Toughness between 0 (feeble pensioner or newborn baby) and 5 (world-class athlete), if you're wondering how long these fights last. The actual negative number past -1 doesn't matter, so any successful hit on someone with 0 Toughness puts them in the Injured box.

Note also the comments below pre-date the March 23rd edit:


  1. Heads up this is just going to be me saying how much I like all of this.

    I love that a broken bottle compared to a fist is about as good as a shotgun is to a handgun. That seems like it would up the amount of franctic scrambling in combat, where you go "Uh shit, I saw Jason Bourne do a thing with a pencil once, is there a pencil around?" "No. But there's a textbook that looks pretty heavy." But that also doesn't stop you from running a game where everyone wants to talk about the difference between a sig sauer an a glock if that's your thing. You get that scene from Pulp Fiction where Butch decides a katana is better than a chainsaw which is better than a bat. That seems like a good thing. In fact that whole act would drop right into this system really easily (donuts vs. a car).

    Also I like that if your main stat is agility or sneaking, you're incentivized to use that in as many situations as possible. This has a kind of emergent thing where a cowardly person is mechanically incentivized to be cowardly, because they will have a greater chance of doing that in clashes. There's no like "my character is bad at combat." Your character might be bad at fighting, but that doesn't mean they will necessarily be worse at getting out of this situation alive.

    Which means I'll get to roleplay what I would actually do in a lot of these scenarios, which is just constantly run away from things and then babble about how crazy that was and should we look it up on the internet or call someone.

    1. yeah, Butch looking at the katana and the chainsaw was a key image in thinking abt this system

  2. Cool stuff! I do think you shouldn't make up dumb names to replace GM, though.

    1. I didn't, I thought up a good name to replace GM.

      You kind of have a history of dumb drive-by comments though so

    2. I liked "Host".
      It is even better translated to romance languages than GM and Storyteller...

  3. Something I've never seen in my limited RPG experience is a rulebook which explicitly lays out important probability distributions embedded in the rules. In 5e, for example, I suspect only a minority of players and GM's intuitively understand how advantage is a bigger benefit for midrange checks than for easy/difficult ones. Granting advantage on DC10 is about equivalent to +5, but at DC19 only +2, etc. You've increased the odds of success by 25% in the former case, about 10% in the latter.

    This is neither inherently good nor bad, but it's less obvious than simply adding a bonus. Particularly in cases where there's debate as to whether or not advantage exists, I know I'd personally be conscious of how the decision translates into percentages.

    I don't know if I read the Clash section correctly, but suppose the rules allow an opposed roll of up to 5d10 vs 1d10. In a straight-up winner take all situation (ties are re-rolled, no crits or fumbles), the implication is:

    1d10 v 1d10: 50% win vs 50% lose
    2d10 v 1d10: 68% win vs 32% lose
    3d10 v 1d10: 78% win vs 23% lose
    4d10 v 1d10: 83% win vs 17% lose
    5d10 v 1d10: 87% win vs 13% lose

    Everyone understands 1d10 vs 1d10 is a 50-50 proposition. But guesses about 5d10 vs 1d10 would be all over the place.

    1. Well they won't be anymore.

      I did plan on including probability tables in there, if for no other reason than to let the GM know what kind of numbers to assign when they do static difficulties.


    2. Cool. I emailed a spreadsheet to your hotmail account with these #'s expanded out (look for 'Demon City probabilities). Hope you find it useful.

    3. Didn't get it:

      Zakzsmith @ hawt mayle dawt calm

  4. Any specific reason for using d10? In my mind that is a very WoD thing.

    1. 2 reasons:

      -It generates ties about 1 in 10 times, a little more if both parties are rolling lots of dice, which is about how often I think you'd want ties in horror (the point of ties is to ratchet up the tension)

      -It works well with having ability scores go from 1-10 (or in the case of this game 0-9 to be exact) which is pretty intuitive for new players.

  5. At first I was wondering why Distraction Die is a separate thing from Situation Dice, but the combat section made that pretty clear. I like the cap on Situation dice for a given action during a Clash - you figure that also applies to any Task? I'd figure so, just so the player could argue merits of their positioning, but only so much. 2 positive situational developments and no more, just to head off long modifier debates in advance.

    For some reason in your example, I was confused that Alfie got a distraction die, when Betty is the one who is distracted. But obviously if you _get_ a distraction die, it's another die to roll, it's an advantage, because your target is distracted. Maybe reading about the Injury die had me confused, as that's the only 'this is a thing' die that is negative. Is the injury die actually rolled at any point, or does having an injury die always just mean you roll one less die? If it's never rolled, I'd suggest calling it just Injury or Injured, more like a status, and that this state gives you the penalty. I was then thinking of injured fitting in with a couple of other statuses (blinded, on lots of percocet) with various effects, but those are really better covered by situation die.

    Oh yeah, I like how even with the 'everyone goes at once' setup, you still have the lowest agility character/entity going first. So the fast folks get time to decide what to do, and can counteract whatever the slow pokes are trying to get done. That seems keen.

    1. The Injury die is never rolled--you make a good point, I'm gonna change the name.

  6. The toughness/damage rules are interesting/surprising, if I've understood them correctly. The target's toughness seems to control both how many points you have to lose, and also how fast you lose them. So if you have a Base Toughness of 1, you roll 1 die for damage, and probably take 5.5, and are probably immediately out of the fight at -4.5 current. (I know you can't actually roll 5.5, am just using the average here for expectation purposes.)

    But having a base toughness of 2 isn't that much better: one hit probably does 3.8, so you are still probably immediately out of the fight at -1.8 current toughness. Base toughness 3 means a hit does probably 3 damage, so you end the round at 0 current toughness (still up?). Base toughness 4 expects to take 2.5 per hit, so goes down after 2 hits. Base toughness 5 takes 2.2 per hit, so goes down after 3.

    Once you reach base toughness 8, the most likely outcome is 1 dmg per hit.

    Question: how do you determine damage taken by an invalid with 0 base toughness? Roll 1d10 anyway?

    1. Good question--the actual negative number doesn't matter, so any successful hit on someone with 0 puts them in the Injured box.

  7. So, um, what happens with Alfie and Betty and CeCe? Most likely example: Alfie rolls 8 and Betty rolls 6 and CeCe rolls 5. So, Alfie definitely shoots Betty. And probably Betty doesn't shoot CeCe, because she just got shot? And does that mean CeCe gets away (even though she rolled lowest?)

    If CeCe had also been trying to shoot Betty, would Betty get shot twice?

    1. Yep, Cece gets away, since Betty got hit before she could act. Alfie, with his high skill and distraction die, saves his friend

      And, yeah, if Cece had been trying to shoot Betty (benefitting from Alfie shooting Betty in the the back) would get a successful shot off at Betty .

  8. The idea of putting the rules on the left hand page and associated notes on the right hand page is similar to how some engineering guide specifications are printed: two columns to a page with the specification in the left column, the commentary in the right.

    1. this is also how the latest edition of Ron Edward's Sorcerer is laid out... rules on the left page, commentary on the right

  9. Oh yeah, one tire-kick thing:

    So stats range from 0-whatever, 0-9 without something supernatural. Toughness in humans is typically 0-5, with 5 being a top-of-the-world level of stamina and endurance. Is toughness a special case in terms of 5 being world-class, or do all the stats work that way?

    I had a bit about how if it was a special case, it might be possible to de-special it by letting 9 be Olympic-grade, but you still only get to roll 5 dice to get damage done. Kind of making the ‘5 dice max’ from clashes a more general rule. With 9 toughness and 5 dice to roll, on average you're 5 hits from being injured, according to Colin's math.

    But that is too many hits, since a Clash isn’t the exchange of damage you see in DnD. Armor will further foul that up, and make battles too long with 9-toughness humans around.

    OK, I think that tire is good then.

    1. Yeah, I think what you're saying is you kicked a tire and it was fine?

      Bc all that is as intended

    2. Yeah you're good. Or the tire is. Either way.