This is a question that recently came up in conversation and instead of throwing it into dozens of IM’s of the discussion group, I thought I’d put my two coppers on it here. NOTE: This is my opinion and just like every other gaming system out there, it is a reflection upon the creators as to what they felt would best serve the game they wanted to portray. There are games out there that have rules that go from 1-500+ pages. I have played in both games with such rules and each game was enjoyable. A different experience and play style but they fit what the creators were trying to… well create. No one way is correct but here’s the way I approach it.

First off: TL:DR – 25 pages.

Now to add the TL to explain it.

There are various portions of a rule book that need to be assembled to make the game function and inform all attendees how things work in the world created (even for modern games): Although I list these in the order I would put them into a rule book, others may feel something needs to be put before others.

Setting – 2 pages
Here is where you go over the basics of the world that the players are living in. You do not need to go into every aspect of every facet of the world here. This is again to give a quick summary of what is happening. This is the first thing new players will read so you want to get their attention. Being a creative writer, I like to spend a paragraph or two writing up a mock scene that a player could be involved with. It helps to draw them into the world.

Introduction – 3 pages
This is where you put the synopsis of the game you’re trying to create. This does not include the setting but more of what your game is about, what you expect from your players, code of conduct, OOG policies, etc. Most of this can be done in 3 pages because usually games (at least the ones I’ve attended over time) usually have a mandatory ‘listen up’ at the beginning of the game to go over them. General rules on the paper, more in-depth discussion/explanation at the listen up.

Character Building – 1 page
This is where a person learns what they need to do to create a character that will operate within the world. Again, it is a short piece detailing what needs to be assembled and not of the individual pieces (such as “Choose 3 skills” not a list of all of the skills or description of skill sets).

Combat – 2 pages
Personal taste but if combat requires more than this, it should be trimmed down. This again is the basics – how do you inflict damage, how do you prevent it, how do you take it, what happens when you take too much and how do you recover from it. The actual specifics of the types of damage is covered in the next section

World history/Setting – 5 pages

Characters interact within a world. And that world need to be detailed a bit more for them to understand where they may fit into things. Give them places to come from, lore of the past, more details about the groups that exist within the world and what the current political climate is like. This also can become overly detailed but I find leaving some things out to allow players to create it for themselves can help build a better world that players would enjoy being in. Although it is a double edge sword so as a designer, you have to be willing to help mold their idea to fit within the world you design and not break it entirely. I find adding in more detail is better to put onto a website so that the rule book itself doesn’t need to be bogged down.

Skills and Abilities – 12 pages

This is where you decide upon what is needed to tell the story and what can be removed for ease of game play.

Here will be the major chunk of the rules and depending upon the game world you want to create, as well as the mechanics, these rules can be as brief or as heavy as you want them to be. It is perhaps the most important part of the rules as it not only informs players what is possible in their world but also how to properly interact with that world. This includes skills the characters can have and any other abilities that the player themselves either can’t or shouldn’t perform at the game (cast magic spells, jump 30 feet down into a ravine, etc.). And this is where things can get dicey and really weigh down a game. The more nuanced a character’s interactions within the game world need to be defined, the more rules that wind up having to be written. My first system had a total of 8 pages of this, with 6 of them being devoted to magic spells. Over 5 years, this expanded to over 50 pages because players found ‘unique’ ways to use the skills and abilities that needed to be clarified and codified.

I have played in systems that had five pages in the appendix of single sentence entries for all of the effects that can put upon an individual (with each effect being detailed more within the rules itself). One game, I had a list of effects on the inside of my shield to know which of them would take my shield out of commission. This type of massive selection works great in a MMO where a computer is immediately applying all effects to the character but if someone needs to know the various different effects between chop, hack, cleave and slice – all being delivered by the same weapon – it will cause confusion that is better removed from the play.

You can decide to have every spell written down, different effects for each one for flavor and so on but in most games, it boils down to the same thing listed in the Combat section above with some slight variations to include such things as how can you manipulate the environment with it. I’ve always said that if all a magic system does is what is listed in the Combat section above and includes only a Light and Detect Magic spell – it’s not really a magic system – it’s just another form of combat. Likewise, superhero abilities, cybernetics, psychic, etc. should have something beyond fighting. Let the fighting remain mostly with those that are carrying weapons.

I’ve played in games where there were no set spells. You could throw any type of spell at someone by speaking what the effect was going to be before throwing it. “By the power of nature I entangle you in these vines!” And again, for the game it worked flawlessly.

This section also includes such things as character species, classes, etc. And just like everything else, the more you want to add into it, the larger this section will be. Needless to say, I prefer to keep such things to a bare minimum with such things as no classes and species being ones easily represented without vast amount of costuming/makeup to help with the immersion.

12 pages may not seem like a lot and I will agree. But if you keep in mind “Try to stick to a dozen pages,” you may begin to see certain aspects of the game that become redundant (sleep, fear, paralyze, etc. all just stop someone from acting until an ally comes over to remove the effect. Maybe just one spell will work) and have players have less things to remember.

So there you have it. This is nothing more than an outline to building a rule set and it is an outline that works for me. And I may have forgotten some sections as well. In the end, if you’re designing a game, it is important for you to put into your rules what you feel will best help to bring that world to life. In the end, it’s your game and if you’re not having fun writing and creating it, it will show in the final product.