Orkish Odyssey

Rules: Crunch and Scope

In discussions about rules-density, whether a game is rules-light1 or rules-heavy, I see a lot of the same arguments being made over and over again. The general consensus seems to be that rules-light games are better for short games or for "story-focused" games, whatever that means, while rules-heavy games are better for deep character customization and tactical combat. Some people say that they dislike rules-heavy games because it’s difficult to "keep all the rules in their head" while others say they dislike rules-light games because it feels like they have to arbitrarily make everything up on the spot.

Hopefully, this essay will contribute at least a little bit of nuance to these discussions, and maybe even give a helpful framework for thinking about how rules change the way one interacts with a game and how much work it demands of players and (especially) GMs.

Adjudication

One problem I have with the framework of "rules-light" vs. "rules-heavy" is that it presumes having more "rules" makes the game is more complex, but what they mean by "rules" is more like unique mechanics or procedures. A game can have a rule that says, "Handle this via GM fiat,"2 but that doesn’t mean the game is any "heavier." More commonly, games will leave things to the GM’s discretion by not including explicit rules to the contrary (a kind of "invisible rule"). For that reason, I’m using "rule" in its most general form to mean, "the way a ruleset handles a specific topic," which may include not handling it, either explicitly or implicitly. Within this framework, all games would have exactly the same number of rules.

This may seem bizarre, but consider that the unique strength of tabletop roleplaying games as a medium is that they can simulate a theoretically infinite number of possible situations. Just because a game doesn’t have an explicit procedure for, say, a PC giving birth, does not mean that this situation can’t come up in play, just that the responsibility is put onto the table (and particularly, the GM) to adjudicate the situation. Whereas Monopoly has no rule for childbirth, D&D does, albeit an unspoken one: "Make something up."

Even when a game does have an explicit procedure for something, the GM must decide when it is relevant and how it should be applied. We can find an example in Lasers & Feelings, John Harper's one-page TTRPG spoof of Star Trek. The rules are simple, especially because characters are only defined by one number:

When you do something risky, roll 1d6 to find out how it goes. Roll +1d if you’re prepared and +1d if you’re an expert. (The GM tells you how many dice to roll, based on your character and the situation.) Roll your dice and compare each die result to your number.

If you’re using LASERS (science, reason), you want to roll under your number.

If you're using FEELINGS (rapport, passion), you want to roll over your number.

Let's identify all the points in this process where the GM is forced to make a judgment call:

  1. The GM must decide whether a PC is "doing something risky."
  2. The GM must decide whether a PC is "prepared," presumably based on their fictional positioning.3
  3. The GM must decide whether a PC is "an expert," presumably based on the role they chose in character creation (Doctor, Envoy, Engineer, etc.)
  4. The GM must decide whether the PC is using Lasers or Feelings.
  5. Finally, the GM must decide how the PC's success or failure manifests: since Lasers & Feelings has multiple degrees of success, the GM must decide how potential complications or extra effects affect the narrative.

I think the most difficult parts of this procedure for the GM are points 1 and 5, deciding when to roll and incorporating the results of the roll into the fiction. It's worth noting that points 1-4 are part of the vast majority of traditional tabletop roleplaying games, and Lasers & Feelings has a simpler system than most: there are only two factors that can influence the probability of a roll (and both are a binary choice of either getting the bonus or not), and there are only two stats used to determine success or failure.

On the other hand, point 5 does add a significant bit of complexity. Whereas many classic TTRPGs, like D&D, have only 2 possible outcomes for a roll (success or failure); each roll in Lasers & Feelings can produce 4 possible outcomes. There are no guidelines for generating these outcomes, and the game trusts (and puts the responsibility on) the GM to create this content themselves.

So, we can see that Lasers & Feelings has some rules which reduce the amount of decision-making the GM must make, and other rules which increase it. Despite this, Lasers & Feelings is considered an ultra-light game because the complexity introduced by the varying degrees of success is not viewed as an example of "heaviness" but rather of the game's "lightness." Why is this? I think it has to do with completeness, crunch, and scope. I’m introducing these terms to describe the way a game’s rules interact with one another and add or subtract work for the players or the GM.

Completeness

The earliest versions of D&D emerged from wargames that required a neutral referee to resolve disputes between players. Because of this, most traditional TTRPGs are a kind of decision-making system, like a court: many games even call the Gamemaster the "Judge." Like a court, the participants at the table must collaborate to resolve situations with an unlimited degree of nuance,4 and the rules of the game thus exist to guide the participants, particularly the GM, to resolve these ambiguous situations.

All systems of decision-making or resolving disputes are in tension between bureaucracy and what we might call adhocracy. Adhocracy, making decisions purely on a case-by-case basis, may yield more satisfying results for the interested parties, but it also increases the amount of time and effort it takes to generate a verdict, and introduces the possibility of the same situation being adjudicated very differently based on the individuals involved. Bureaucracy is the opposite: a heavily standardized system where the adjudicating party has less input on the final verdict, which will yield very similar results across a variety of different scenarios, yet may overlook the unique circumstances of a specific situation, which could dissatisfy the interested parties. The more guidelines and procedures there are to constrain the judge, the less unique and tailored the verdict will be.

This is more or less what I mean by "completeness." The more complete a game is, the more it will resemble a pure bureaucracy, because little to nothing will be left to interpretation. As I said before, no game will be 100% complete because there will always be a need to adjudicate things like when to call for a roll at all, but the more complete a ruleset, the less decisions are required to actually play and run the game.

A complete ruleset is not necessarily a satisfying one, however. Here is a nearly complete ruleset: "If you are unsure whether something will happen, flip a coin. On heads, it happens. On tails, it doesn't." This is an extremely comprehensive ruleset, leaving almost nothing to interpretation. Nevertheless, I suspect most people would be dissatisfied playing a game which would struggle to accurately simulate realistic probabilities.5

Crunch

This is where crunch comes in. I use "crunch" to mean "the degree to which a system mechanically differentiates between elements of the in-game narrative." For example, in our hypothetical 50/50 system, there is no way to mechanically quantify a person’s skill, so long as there exists any doubt about whether they will succeed or fail at a given act. A master of swords is defined by the mechanics in the same way as a complete novice. This system has effectively no crunch.

A crunchier, but equally minimal system, might tell the GM "If you are unsure whether something will happen, determine its likelihood out of 100% and roll a d%. If you roll under, it happens. Otherwise, it doesn't." Now, the GM has a way to give the master better odds than the novice of winning a given duel. Crucially, however, this increase in crunch reduces the completeness of the game: the GM must now choose from 100 different possible difficulties each time something might happen, where before they didn't have to make a choice at all.

We can say that the opposite of crunch is flavor. In the 50/50 system, even if the master and novice had equal odds of winning a given duel, we can still describe the master’s sure, devastating strokes, compared to the novice’s inept, clumsy swipes. A rule that increases crunch thus removes "flavor," in the sense that it makes what was previously a matter of describing the fiction into a mechanical reality. Conversely, rules that reduce crunch and increase the completeness of a system by consolidating different elements of the fiction under a single mechanic or procedure create flavor.

For an example:

Scope

Scope is the other half of the puzzle. Whereas crunch and flavor are terms that get thrown around in RPG discussions already, scope is a little bit tougher to explain and define.

When I say "scope," I mean "the degree to which the consequences of applying a procedure are defined." What does that mean? Well, whereas crunch requires the GM to make finite decisions (damage on a scale of d4 to d12, a 1-100% likelihood), some rules ask the GM to make more unconstrained decisions.

Rules with a narrow scope produce gameplay: having rules for weather events, foraging, and random encounters in the wild (like many OSR games) means that wilderness exploration creates its own emergent narratives, simply by following the procedures. While the GM still has to keep track of all these rules, and may have to do some bookkeeping, the specificity of these procedures means that a lot of the actual events of play are handled automatically by the rules themselves, as if the game were "playing itself," rather than being devised by the GM.

The best examples of rulesets with a narrow scope come from games which have a predefined "gameplay loop," like Night Witches or the Carved from Brindlewood games. Night Witches is a Powered by the Apocalypse game about female Soviet pilots during WWII. Playing the game, there is not only a set structure of prepare for mission > briefing > mission > debriefing, but a lot of the moves have consequences with hard mechanical effects on later actions. The Carved from Brindlewood games are all about various types of detectives juggling episodic mysteries which feed into a larger plot: while the GM is expected to do a lot of improvising moment-to-moment, the overall structure of the campaign is already determined by the ruleset.6

The opposite of narrowness of scope is broadness, or rules which give the GM a significant degree of latitude in how to apply them. An example of this is Lasers & Feelings’ multiple degrees of success: there are no guidelines for what entails a "complication" or an "extra effect," meaning the GM comes up with these consequences with basically no constraints. This is not a very narrow rule, it’s a very broad one, and thus creates work for the GM by introducing incompleteness. If each level of success had a predefined consequence, like a character taking "Stress" instead of getting a complication, that would be a narrower version of the same rule. In terms of play structure, a broader approach would reject having a predetermined gameplay loop in favor of allowing the ruleset to be used for a wide variety of different stories. This means the ruleset is more versatile, but only because the GM is expected to create or provide the actual scenarios the PCs will play.

Applying This Methodology

We’ve established that rules can do 4 things:

Crunchy and/or broad rules introduce ambiguity to the game which requires GM interpretation, while flavorful and/or narrow rules do the GM’s work for them, which makes running the game less effortful but also takes away some of the GM’s control over the fictional world.

How would these categories apply to rulesets as a whole?

Broader, more flavorful games would have few explicit procedures which can be "reflavored" to describe a variety of different characters and fictional situations, as well as rules which expect the GM to do most of the work of creating the story of the campaign. A good example here would be Fate: Fate is intended as a generic game which can be used to tell almost any kind of story the GM has in mind. It does this by defining almost everything (characters, locations, objects) with the same mechanical building blocks.

Narrower, more flavorful games would have few procedures, but would tie those procedures into a mostly predetermined gameplay loop. The more focused, more specific PBTA games tend to be like this, including Night Witches, as I described above. Lighter OSR games can work like this as well, assuming you are mostly running pre-designed dungeon and wilderness adventures.

Broader, more crunchy games would have many intricate procedures and mechanical distinctions, designed to be used for a wide variety of possible stories. Fate’s crunchy cousin GURPS is a pretty good example of this. Whereas Fate has the same versatile building blocks for all characters, GURPS requires the player to pick from a looooong list of unique abilities meant to simulate nearly every possible trait of a character.

Narrower, more crunchy games would have in-depth procedures meant to be applied towards one specific system or gameplay loop, often combat. Even more general systems like GURPS or recent versions of D&D and Pathfinder tend to work like this if you look specifically at combat. A good example of this might be Lancer: I’m not extremely familiar with that game, but I hear it described as very "board game-y," which one would expect from a game that is crunchier and more specific.

Conclusions

I hope this framework makes sense and casts some light on how rules in games can both create and reduce work for the GM. I really tried to be clear that I don’t think having more work for the GM is a bad thing necessarily, since it also means the GM can tailor their rulings more precisely. Nevertheless, I prefer not having to work as hard when I’m GMing and it’s been useful to think through what rules decisions contribute to that. I also don’t think this framework is binary: a rule’s level of crunch or specificity can only really be described in comparison to other rules, and I don’t think games are inherently one thing or another but exist on a spectrum.

Footnotes

  1. Is it rules-light or rules-lite? I can never tell.↩

  2. GM fiat is when the GM arbitrarily or unilaterally says something is the case. For instance, if a game doesn’t have explicit procedures for determining things like weather, the weather is determined via GM fiat.↩

  3. Fictional positioning is whether, in the context of the game, the player has whatever necessary tools they would need to perform the task, like a doctor having a scalpel for performing surgery.↩

  4. This is to say, there is no limit to the number or kinds of factors that might affect any given decision: the only constraint is an individual’s imagination (or more likely, ability to process information).↩

  5. My new TTRPG, Coin Flip, is hereby released under CC0 (No rights reserved).↩

  6. Some games kind of do this without being explicit about it: many OSR games assume GMs will use prewritten modules, and thus don’t feel the need to include rules for making your own dungeons or wilderness adventures.↩

#orkish odyssey #osr #ttrpg philosophy #ttrpgs