The Foundations of Fun
Basic Decisions when Designing RPG Mechanics
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I hope you enjoy reading and please feel free to leave comments
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There is a great wealth of knowledge of Game Design that can be found online if you have the patience. There are forum threads describing abstract theory, blog posts on novel techniques and the occasional dialogue on Twitter on the underlying philosophies. It can be a challenge to learn though, since they tend to be I thought that it might be useful to have a high-level overview of how mechanics function and that such a document could be a boon for new designers.
Disclaimer: I am neither a wealthy nor a successful designer. I don’t even manage to play one on TV. I have more then a few years of experience in the craft and spend far too much time reading up on game design theory and technique, but that’s it.
What this is about
Each game is fundamentally built out of a series of choices, each informed in turn by your central design premise. Rather then examining each particular application, I am focusing on providing a high level overview of the general types of decisions you will have to make. The major decisions fall into two categories; what kinds of Traits are on the character sheet and how that interacts with the Resolution System. Once you use this to build the skeleton of your game system, you will be able to go into depth and determine the specific traits and formulae. Those details will allow you to encourage specific behaviours and focus the style of play to meet your needs. That is where most of the real challenges lie, once you build a foundation
Traits
The typical format of an RPG has multiple participants who play different roles in the game. These characters are differentiated by the various Traits they possess. I am using the most generic form of the word to represent attributes, skills, aspects, abilities, merits, flaws, cash and an y other element written on the character sheet. This is intentionally broad and represents the Cues/dice in Vincent D. Baker’s “Clouds and Arrows” article in the Further Reading Material.
1 How many different Traits?
The number of traits is a good measure of system complexity. The more Traits, the more variables that a player will need to account for during play. Often some Traits are lumped together in categories to represent differences. For instance, Melee, Archery and Riding might all be Traits in a system where they are all categorized as different “Skills”.
1.1 Games with Few Traits
There are a number of advantages of a system with relatively few distinct traits. Fewer traits mean that the game system is proportionally easier to learn, to recall and to teach to others. These games are usually friendly with new players and allow for quick character generation. These lightweight games tend to be friendly to improvisation and will naturally reinforce character actions as driving the story forward.
Examples: Dresden Files RPG, Savage Worlds, Dogs in the Vineyard and even 4th Edition AD&D.
1.2 Games with Many Traits
These types of games tend to be more complex and more precisely describe the player characters. Many traits mean that the game models more complex interactions between the character and different elements of the settings. These heavyweight games tend to do excellent jobs in modelling certain situations in game and can promote a sense of realism. The heavyweight games tend to be friendly to planning and will naturally reinforce character concept/capabilities as driving the story forward.
Examples: GURPS, Hero System or Rifts.
2 What is the Scope of the Trait?
Each Trait has a range of situations where it applies. Athletics may be defined in the book as allowing running, throwing and climbing but not swimming (Proscriptive traits). Alternatively, the player may decide to write in “Track and Field” on their sheet and interpret the trait during play (Descriptive traits). The question is whether the applicability is defined by the game designer in advance or by the player in game.
2.1 Proscriptive Traits
These types of traits are common in RPG’s. The designer tells the participants exactly what each given trait does mechanically. Trait A will only apply in these situations, and will behave in a predictable fashion. This dates back to the early versions of Dungeons and Dragons where thieves might have a score in “pick locks”. It’s very clear that exactly what those traits do mechanically and there will be no confusion on where that particular trait applies. As a natural result, it limits the number of possible actions that a given PC might perform. This often allows for the designer to focus the style of play to match certain themes, moods and settings.
Examples: Almost every RPG in existence has proscriptive traits. Most systems have Skills as clear proscriptive traits.
2.2 Descriptive Traits
Descriptive traits are rare, but have been appearing more and more of late. The participant writes in some statement, question or word for one of their traits. When the player, GM or group determine that the trait is relevant, there is some mechanical effect. This means that almost every trait is unique in applicability and each player has drastically different capabilities. As the traits are determined by the player, they are custom tailored and flag exactly which issues and actions the player wishes to focus on. Descriptive traits also have the merit of being flexible and usable for any setting, as it is the player who determines them.
Examples: Unknown Armies (Skills), Dresden Files RPG (Aspects), Burning Wheel (Beliefs).
3 What values can the Trait have?
Once you know _what_ each trait applies to, it comes down to deciding what possible mechanical effect those traits have. While I know you haven’t determined your precise mechanical system yet, you will need to know what variables will feed into it.
3.1 Binary Traits (Lever)
Binary Traits, also known as Levers, are traits that have two values. They can have a value of Yes, meaning that the Trait exists and will apply the mechanical affect within it’s scope. Otherwise, the character doesn’t have the and it will not have any mechanical effects. Levers are simple to remember, easy to learn and fast to apply during play.
Many game systems treat languages as Binary Traits, with characters either fluent or ignorant of the language in question. Another common use of levers is for special traits called “Conditions”. When a character is stuck in the head, they may have a condition of “Stunned” which would have certain mechanical effects.
Examples: Dungeons and Dragons (Languages, Feats, spells), Storyteller System (Some merits, flaws)
3.2 Fixed Traits (Score)
Some Traits are fixed in values and are referred to as Scores. Other then occasional improvements, each Score will remain static. These are qualities have predictable and consistent mechanical effects whenever the Trait applies. It’s the most common type of Trait in existing roleplaying games. These are just written as integers on the character sheet most of the time.
Examples: Dungeons and Dragons (Attributes), Storyteller System (Skills)
3.3 Variable Traits (Dial)
Variable Traits, referred to as Dials, change frequently during play. Each Dial will have a minimum (usually zero) and a maximum value. The value of the Dial provides some mechanical effect and/or interacts with the resolution system. Conversely, certain kinds of events in the fiction can change the value of your Dial. These are the most customizable, complex and compelling types of Traits. Usually Dial Traits are tied to the players long term concerns and goals.
Examples: Don’t Rest your Head (Madness Dice, Discipline Dice, Exhaustion Dice) or Vampire: the Masquarade (Humanity).
3.4 Resource Traits (Currency)
Resource or Currency Traits are similar to Dials, but they have no maximum. They have values from zero (no resource) to potentially infinite. Resources can either be diminished in play or increased, but the actual amount of currency usually has no mechanical effect in the game. Often Resource traits function as “cheat mechanics” which allow for players to affect their chances of victory in specific conflicts.
Examples: Dungeons and Dragons (Gold, XP), Dresden Files RPG (Fate Points), Buffy RPG (Drama Dice).
To Be Continued