Boons & Banes Dice System
Posted: August 20, 2021 Filed under: Patreon Leave a comment »So hey I thought I’d talk about the dice system I’ve been working on!
First up, the system is basically;
- Roll one die for things in your favour (these are Boons)
- Roll another die for things against you (these are Banes)
- Whichever die rolls higher decides whether the roll is a success or not.
Which dice you roll are determined by your boons/banes. Put simply, you just double the number and that is the die you use (eg; 3 Boons = d6, 5 Banes = d10), and for 7+ you just roll a d20.
I have been building my RPG DreamSent around this system (the last pdf has a version of it before I had the major “AHA!” moment of rolling boons against banes rather than adding them to some other roll), and I included a trimmed-down version of it in The Chamber.
The system can support more than binary success/failure outcomes too; when you need a scored/quantifiable value you can just subtract the Banes result from the Boons result. And it has the equivelant of critical success/failure if one die’s result is 1, and the other is 4 or more.
That is essentially it, that’s the whole system.
For DreamSent your Boons are the same as whatever character stat is being tested (eg Test of Finesse -> Finesse stat is 2 -> You have 2 Boons), and the GM decides how difficult the task is, specifying how many Banes you have (and they may also grant you extra Boons if something is helping your character).
How I came up with the system:
The system started out as just a “Roll a d10, add your stat” type deal, then I left it alone for a year as I worked on other projects, and when I came back to it last month, I decided I liked d12s more than d10s. Dodecahedra are just pretty OK? Anyway, obviously this is nothing like how the system turned out.
In that year I found Lancer‘s dice system, which I love. I really do. The core rulebook has a free version you can check out (but I also recommend the complete book so you can read the lore which is JUICY AF). Put simply; with that system you have things called Accuracy and Disadvantage, which determine extra dice that you can add to (or subtract from) a d20 roll. I love that more than the classic “Add a stat” approach because… well, I like dice. rolling more dice is cool! (but also not-cool, see below!)
I basically grabbed this system for myself and changed its mechanics a teensy bit so that the theft would be a little less blatent (I changed the terminology and instead of rolling more/less dice, you roll bigger/smaller dice)
At this point my dice system was:
“Roll a d12, add your stat, add Boons OR subtract Banes”.
Honestly it didn’t require any testing to see that it was a huge mess. But I wasn’t looking too hard at it for a while so I think it’s that way in both of the DreamSent pdfs I’ve put up here rn, sorry :p
Anyway eventually I started thinking about how I hate stat modifiers. I really just, I hate them. tbh I hate doing maths at all, it slows me down. So I thought “Stats can determine Boons!” and boom, I got rid of a third of the roll system. Once I did that, I really got into the weeds and went HARD into probabilities and the like by testing things using anydice (wonderful site!), and saw there were significant gaps in the range of likely possible outcomes of one bane vs one boon vs none.
Adding d2s to the system filled the gaps, so the probabilities of increasing boons/banes changed in a more intuitive way – and it had the benefit that doubling the numbers of boons/banes told you which dice you should roll.
After that, I added a fixed difficulty value for rolls to beat in order to succeed (so it was less work for the GM, and everyone knows what number they are aiming for. Fixed difficulty in RPGs is lovely, I hate rolling and not knowing if it was good enough – I see the number so I should know if it was good enough!).
To add fixed difficulty I just picked a number (6, because it’s the generous side of an expected d12 roll) and made it so that Boons/Banes did not cancel out (a vestigial mechanic from stealing Accuracy/Disadvantage mechanics from Lancer) and instead both are rolled. At this point the system was:
“Roll a d12, add the Boons die, then subtract the Banes die”
As soon as I added a fixed difficulty though, I realised it made no sense in terms of like, why is 6 the number to beat? It was a value only determined by the dice and nothing to do with anything that is part of the game world. (A few RPGs do this of course, the average/expected roll sets the standard difficulty/ability. It’s why ~10 is the baseline for any system built around a d20, why ~7 is baseline for 2d6-focused games, etc).
Another issue with my fixed difficulty being 6 is that honestly, it’s different to other RPGs. People are used to 10 being the base, so I started thinking about making the ‘core’ die a d20 instead of a d12, but THAT was when I had my “AHA!” moment – If I was trying different core dice, then why not just go with NO dice? Just roll “Boons – Banes”, the target difficulty is always 0, positive is good and negative is bad – it’s super intuitive!
Mechanically, that was essentially it for the design, but it wasn’t until after a day of rolling one die and subtracting another that I realised 1) I am bad and slow at even simple maths, and 2) I didn’t have to be good, because most tests don’t require a score, you just need to know which number is bigger to decide whether you succeed.
Things I like about the system that I will take credit for as if they were intentional:
The system only ever has two dice rolled at a time, I know I might seem like the kind of person who would prefer hundreds of dice rolled all the time (and I ABSOLUTELY AM) but my experience with dice has taught me a lot about rolling groups of dice. Firstly, it is slow to count dice results – not everybody has a world-class dice roller and totalling stuff can slow down an RPG a lot. Secondly, the more dice you roll, the less point there is in rolling – the outcome actually becomes more predictable (it’s a probability thing, probability is WEIRD).
Rolling two dice is IMO the sweet spot for ease of use, having a nice normal distribution of the possible outcomes, and being intuitive for what might happen as a result of your roll.
Also, even though my system has only two dice rolled at a time; YOU GET TO USE ALL THE DICE! ALL OF THEM!
ALLLLLLLL OF THE DICE!
I love different dice shapes, they are great, but you so rarely actually have a justification for having a full set! The B&B system though? You might have to roll anything – who knows what you’re up against! And as a bonus, if you want to roll Boons and Banes at the same time, it’s worthwhile having TWO sets of different colours!
You don’t need two sets of dice, but omg if you want a justification for grabbing two sets of contrasting dice it’s here!
Goodness I love dice so much!
Wrapping Up:
Anyway that’s pretty much it for this sytem, so I’ll stop here and wish you well. Look after yourselves and the people around you! <3
Also, here are some extra tables from my DreamSent manuscript about the dice system
<3