Content in RPGs: bones, fat and skin

This is a translation of a post originally published in 2018. More posts in English here.

Bring me the fat!

Greetings, munificent readers. These days I've been thinking about what types of content are in a RPG (at least as a game, not as an activity). Beyond the classical division of setting/system I propose one made of three parts: bones/fat/skin.
Bones are base and general mechanics that articulate the game and stablish its structures. A combat system is bones, for example.

Fat is pre-made content to be used in the game, the moving parts that add opions: inventory, classes, spells, monsters, traps... For a in-depth discussion of what is fat and how are fatty games, I reccommend this article.

Finally skin is the aesthetics or appereance of a game, including background, flavor text, pictures, etc.

If you fight in a game, that's a bone. If you use a sword with different numbers than an axe, that's fat. If the sword has the names of all your ancestors written with runes, that's skin.

That way, games can be describes as more or less bony depending on the number of rules they have. More or less fatty according to their libraries of content. And more or less skinny depending on how ornate it is, etc. Even games with "loose skin", for example, if they have illos of creatures that never show up in the bestiary.

I think it's a pretty apt distintion, as it solves the slippery and sticky problem of the fat: is a spell like Sleep setting or system? Of course it's part of the system, being a mechanical piece, but the fact that it exists it's also telling us something about that world's setting.

And none of the thre types of content is purely system or purely setting in an RPG, given it's holistic nature. If elves, in that setting, wear armor made of sea dragon, even if they are mechanically identical to plate armor, good luck trying to get rid of them with "Heat metal", for example.

On the same token, bones modify the setting in more subttle ways. This can be clearly seen in generic systems (that are, in the end, just a skelleton, with some optional fat), that usually include optional rules for different settings, genres ore tones (all of that part of the skin). Because, for example, how deadly the combat is has a huge impact on how the game world is.

It's interesting that geneneric systems with more fat also have more optional rules, and given that they are relatively mobile, you can guess that those rules are a bone type close to the fat.

On the other hand, in the same way that many classic generic games are just bone and fat, many narrative games are only skin and bones: a base mechanic and background, ready for the group to introduce fat together making it up in real time.

Of course this brings another problem: what are NPCs? Because, of course, they are also content. Of course their stats are fat (even if second grade, as they are not an integral part of the system), but what about the rest? How much is background? To what extent the way NPCs interact outside combat, even without explicit rules, is bone? This is the kind of question that don't let me sleep at night.

But, even then, I think this is a good paradigm to comprehend what RPG material is composed of, to classify better its content and see how to enrich our own games. What do you think? Do you think the cathegories are appropriate? Do you think that fat is the best thing in the world and there is never enough? Leave some comments down below and thanks for reading me. Valmar Cerenor!