RPG Design Journal #1: Choosing a Core Mechanic for Avar Narn RPG

Reader beware: this post is as much me working through design ideas as it is describing design choices. If that’s not interesting to you, but RPGs are, just wait until I’ve posted something more concrete about the Avar Narn RPG’s systems.

I can’t tell you how many times I’ve started work on an RPG ruleset for Avar Narn and then stopped.

Here’s a list of rulesets I’ve used to run games in the Avar Narn setting over the years (as the setting has developed and grown): The Riddle of Steel, D&D, Fate, Cortex Plus, various custom systems.

And here’s a list of systems I find (to varying degrees) influential on my own design approaches: Shadowrun, World of Darkness (particularly nWoD Mage: The Awakening), Dogs in the Vineyard, Fate, Cortex Plus/Prime, TRoS, Warhammer Fantasy, Apocalypse World, Barbarians of Lemuria, Artesia: Adventures in the Known World, Shadows of Esteren, The One Ring, Stoltze’s One-Roll Engine (and particularly Reign), John Wick (especially Houses of the Blooded), Blades in the Dark, Fantasy Dice, GUMSHOE, FFGs system for Star Wars and WFRP3e, Burning Wheel and Torchbearer. Yes, that’s a lot of varied designs with some ideas that are incompatible with others.

Having mostly cut my teeth on dice pool systems, that’s my typical starting place. I’ve read a fair bit on game design and, this time I’ve decided to start at the very beginning, without preference for a core mechanic. Here are some links to give you some background on things I’ve been thinking about as I do this:

“How Do I Choose My Dice Mechanic”
“All RPGs Are FUDGE” (while I see a little more significance to the variation between systems than this author, the point that statistical variations in the most-frequently-employed core mechanics are not as significant as we might think seems pretty sound)
“Design Patterns of Successful Roleplaying Games”
The Kobold Series on Game Design
Robin Law’s Hamlet’s Hit Points and John Wick’s Play Dirty (although these are more about running games than designing them)

I’ve spent a lot of time trying to analyze the statistical differences between core mechanics (though math is not my strong suit, and particularly when it comes to complex probability equations) only to come down with a bad case of analysis paralysis.

Here’s what my recent reading (and experience) has led me to conclude:

(1) When the rules serve their purpose well, it’s the story that gets remembered, not the results of dice throws.
(2) The actual statistics of a core mechanic are less important than the way we perceive them–the way (our view of) the dice mechanic reinforces (or undercuts) the feel of the game and setting is what matters.
(3) The most interesting thing about a core mechanic is how it can be manipulated with interesting rules that are intuitive and yet reinforce setting ideas. Thus, a core mechanic should be selected more with an eye to what it can do for subsystems and design goals than its own merit.

Here are some of my analytical conclusions so far:

(1) Efficiency is paramount. The more you can resolve with a single die roll the better. Dice pools are often faster in use than roll and add/subtract systems because counting successes is easier than addition. Is it easier enough to force a design change? No.

(2) Inspired by the FFG custom-dice game: if a single roll can give you both the main pass/fail and degree of success information and give you cues for scene complications or opportunities, so much the better. The One-Roll Engine is also good at this. Additionally, checking the dice for multiple conditions should be simplified as much as possible so that this feature does not carry with it too hard a hit on efficiency.

(3) For a gritty setting like Avar Narn, a bell-curve or Gaussian distribution makes sense for three reasons: (a) extreme results are made more rare for a more “realistic” feel, (b) character stats are more significant in a bell-curve distribution than a linear distribution, and (c) along with (a), these distributions give more predictability to players as to results, which is important in a game where consequences of actions (including but not limited to lethality) are severe. The binomial distribution of dice-pool systems aren’t so far off as to be ruled out by this, but do not fit as well as a multiple-dice roll-and-add system.

(4) Along with a bell-curve or similar statistical distribution, the “bounded accuracy” of the latest iteration of D&D helps create expectations reliable enough for players to reasonably predict the results of courses of action.

(5) Combat requires a delicate balance–it must be fast, but it must also grant enough tactical depth to be interesting for its own sake. Additionally, it must be intuitive enough that advanced lessons in martial arts are not necessary to use the system to its fullest. One of the ways to make combat quick is to make it deadly, but combat that is too deadly is not fun for players. This is exacerbated if (1) the game intends deep and serious character development, (2) the “adventuring pace” means that injured characters must take a back seat for an extended period, or (3) character creation is time-consuming and/or complex. I’ve got a number of ideas for streamlining combat, but that’s for another time.

(6) Rules principles that can be applied to many different scenarios are far better than complex rulesets. Fate and Cortex are the best at this, in my opinion.

So what does all of this mean for Avar Narn RPG? Despite my love for dice-pool systems, I’ve currently leaning toward a 3d6 system, or perhaps even the use of Fudge/Fate dice. The 3d6 is more accessible for newbies into RPGs, but it’s probably more realistic to expect this to be a niche game. And, to be honest, I’d rather have a dedicated group that loves the system and setting than having to try to cater to a large base with very diverse expectations–especially for a first “published” (read: publicly available) system.

My apologies if you were expecting a solid answer on the core mechanic in this post! Right now, my action items in making a final decision are as follows: (1) determine the subsystems the game will need/benefit from, (2) play around with manipulation rules for various core mechanics, (3) find the core mechanic that checks off the most boxes.

Thoughts from those of you who have tried your hand at RPG design?