RPG Design - Road to MVP: Core Rules

It was now time to put my research to the test. I have written so many notes in a notebook over the last few months (even before I started seriously working on A.D.A.) and I now had to go over them and bring them in a format to be usable. My first goal was to make a Minimal Viable Product (MVP) - a set of rules and descriptions so you can play a game of A.D.A.

The rules are in no way complete and will probably contain little fluff - it doesn't make sense to design 100 monsters if at a moments notice the way monsters work and how they are described changes. It probably is not balanced either or isn't even fun. The goal is to have something to test and iterate in order to filter out the final rules.

Nonetheless I want to write down my thoughts on why I choose certain things so I can later go back and compare my reasoning and what to adapt.

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Basic Field Training

First things first are the core rules - this is what I call the rules that describe what characters are, what they can do and how they might fail at doing these things.

My first decision was to use an existing system and hack it to my needs and ideas. The reason was, that I could focus more on the main game loop instead of trying and fixing the core mechanics. This way I had an already functioning system and I only had to test if my changes are viable.

The downside to this is of course the sheer number of systems out there. Each of them sound interesting and I could probably make them all work. Since A.D.A. can be played solitaire, I wanted a system that created tension and conflict in itself - a job normally done by the Gamemaster. This also needed conflict resolution to be player-facing (or player-driven) - the character values determine the outcome directly, not by decision of the GM.

Early on, I had my eye on FATE. Actually that is how it started. I played some FATE and thought I wanted to make an RPG with that system. I could have done just a setting for it, but then came a global pandemic and Ironsworn and I decided differently. I really like the concept of Aspects. They are sort of like a prompt what is currently happening and you can act upon these aspects. It was also already a heavy story-first RPG.

Actions and Conflict Resolution

FATE uses "special" dice to determine the outcome of actions though. A die can show +, - or nothing and you "add" four of these dice up, to get a result of -4 to +4 with a non-uniform probability distribution (rolling 0 is more likely than +1, which is more likely to roll than a +2 and so forth). To this you add a modifier - mostly the skill or approach you used for the action. There are other things here, like invoking and compelling aspects, but lets ignore this for a moment. This is your final score that needs to beat a difficulty that the GM determines.

So far it sounds just like a bit more complicated Dungeons & Dragons. But there is a bit more to it. There are actually four different outcomes instead of two: Fail, Tie, Succeed and Succeed with Style - depending on the amount you rolled over or under the target difficulty. And the probability curve means that your end score is likely the same as the skill you were using to do the action. So, depending on the difficulty set by the GM, you would need to interact with the aspects around you in order to create advantages and gain a bonus on your roll. What is also interesting in the system is that you can do that after you have rolled and seen the result.

The problem with this system is, that you need a mechanism that sets your difficulty, as it is not entirely player-facing. You could go with just the interpretation of the result according to the FATE ladder but that didn't sound right to me.

My first idea was to introduct some sort of Chaos Factor (like Mythic Gamemaster Emulator that determines the general difficulty you have to beat. So it would start at CF1, which means the difficulty for all rolls would be +1. It can be increased to up to CF5. I had then to come up with a system to increase (or decrease) that factor somehow. The reason why I didn't choose this option though was, that it introduced a bit too much bookkeeping. You had to track the Chaos Factor, your FATE points and other stuff. So if I can get rid of this the better.

So I needed a different resolution system. I came across Blades in the Dark. In essence it was a dice pool system, which counted 6 as successes. But in addition to that it also considered other results, so it ended up having four different outcomes as well, that match perfectly to the FATE outcomes. So there is no need to track any chaos factor and with it came a simple oracle system (to answer yes/no questions) as well.

So lets now have a quick look at invoking and compelling aspects, which I glossed over before. In FATE you have a certain amount of points that you can use to invoke aspects. You describe how an aspect is to your advantage (or disadvantage to the opponent) and you get a bonus from it. By invoking an aspect you get +2 to your score or you can reroll all dice. You can even invoke multiple different aspects to get even more bonuses out of it. These invokes cost you points so you need a way to gain them. That is where compelling aspects comes in. The GM (or even the player himself) can compel an aspect to gain a point, but in general automatically fails at that action or something really bad happens. Compelling can be seen as a way to introduce even more conflict into the game.

Now that I had changed the dice mechanics of FATE I needed to slightly adapt that. Instead of giving a flat +2 (what would that even mean), I decided that when invoking you can give one die +1. So you could turn a 5 into a 6 and thus get a success or even a critical success (success with style). Other than that I didn't had to change much. I also introduced free compells as kind of counterpart to free invokes - these are like invoking an aspect but doesn't cost a point. Certain outcomes of actions generate a free compel, a compel that has to be taken next time around and thus create that conflict without a GM.

FATE knows four different actions: Create Advantage, Overcome, Attack and Defend. The first two have to do with aspects, whereas the latter two have to do with combat. Create Advantage and Overcome are used to either create aspects, use them or remove aspects. These can be used more or less how they were. I added free compels where it made sense (when you failed a create advantage for example).

With that I more or less had my core mechanics, except ...


In FATE you have two actions for combat: Attack and Defend. It is basically a oppossed dice roll and the difference between the two rolls determine the outcome (instead of the dice roll itself). Since I didn't have a score anymore with the new dice system and I didn't want to roll multiple dice sets I reduced this action by one single one: Skirmish.

The idea behind this is similar to what Ironsworn does: The outcome also determines if you keep the upper hand in the fight or if the opponent is able to land a blow because you left an opening to be used. That way it is entirely player-facing, the outcome of the dice roll of the player determines what happens and not what a GM might roll. So when you don't succeed you might get hurt along the way. There is also no track on whos turn it is and the different actions that can be done. Think of it like when you read a book that describes the fight from the perspective of the protagonist.

The issue with that system might be, that the opponent can't create advantage or invoke aspects against you, like it would be able to do normally in FATE. I hope that this is somewhat covered by the modified outcomes of those actions. In addition the opponents only "scale" with the amount of damage they can take, since they don't actively hit back. That is definetely something I have to keep an eye on during playtesting.

But what does it mean when you get hurt? In FATE you get assigned stress. This is a more broad term for your physical or mental state. So no matter what the source is you take some amount of stress. When you take enough stress you take scars. These are called Consequences in FATE but work a bit differently - there you would use consequences to soak up a certain amount of stress. I like the system in Year Zero a bit better (or to some extent Blades in the Dark) better which is what I settled with.

After you are full of stress, every hit after that creates a scar. They come in different types (like the consequences in FATE) - which differ in how you can heal them. If you then take enough scars you are out of action (most likely that means dead). In a way that way it behaves like stress (you just accumulate) but at a certain point the stress becomes "visible" and thus are scars - which are also aspects.


So, now that the How is covered, lets have a look in to the Who. Character creation in FATE is pretty straight forward. Just create some aspects and rate some attributes. There are two subsystems in FATE. There is the FATE Core way with skills and there's FATE Accelerated Edition (FAE) with Approaches. I first thought of using the Approaches from FAE. After some games with FAE I decided against them. The reason is, that the approaches are a bit overlapping. That is probably intended but didn't feel right to me. I needed the player (or character) to fail in order to create conflict, but the approaches somewhat encouraged the use of your strongest one.

So I settled with the FATE Core skills. I reduced their number to 12 only and put them into 3 categories. This allowed me to give additional rules to use the category (I called them Traits) in actions, when no skill would fit. Lets see where I can go with that. The skills can have a rating between 0 and 4 which is the number of dice you roll for the actions.

A character has three aspects at the start: High Concept, Believe and Impact (the latter two replacing Trouble). This is the personality of a character.

What I also saw in other system is the use of playbooks, archetypes or plain classes. This is an interesting concept. My idea is to provide such playbooks in order for the player to get started faster. Especially when it comes to FATE stunts (Abilities in my system). I would provide the player with some options he can choose one of. I don't know yet if I want to give similar prompts for the Personaliy Aspects as well. There is this concept of Employee Types which I think could thematically fit in here. These are based upon the Myers-Briggs test (which is absolute bullcrap - but I let Adam Conover explain that), but it fits perfectly into the bureaucratic theme. For now I just give an outline to that in my rules. There might be changes to the character system so lets not detail that too much out. So if you want to play just play without abilities and just give a High Concept and Impulse.

Other bits and pieces

Some of the outcomes produce consequences. These are prompts for the player to introduce some sort of conflict into the scene or world. Normally one of the tasks of a GM, I needed something to help the player. So I added some tables to roll on to give a prompt. I came upon two nice tables (I think they came from Fateless but I'm not exactly sure anymore). There are two types: Minor and Major. I could imagine using these a bit more in the game loop. I adjusted them a bit to my liking.

And last but not least I also added the obligatory Yes/No Oracle. As mentioned before you can choose the likelihood and roll a different amount of dice (0 to 3) and get a result. To make things interesting, There is a "Yes, but" option which creates another consequence.

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