As an alternative to pre-fabricated game worlds (whether published or home-brewed), I'd like to create some rules for generating a game world gradually and organically.
It would work in a manner analogous to the "fog of war" in some strategy games. As player knowledge of the world expands, either through direct exploration or knowledge checks, details come into existence.
How is this different from any GM who just makes it up as they go along? Because I'd like some sort of pre-established rules mechanic for generating new countries, cultures, geography, etc. This mechanic would be based on part on player decisions, in part on GM decisions, and in part on randomness.
Has anyone ever published a rules set for world creation like this? I'm thinking in terms of a fantasy setting, but I'm open to all genres for suggestions.
Best Answer
In Mystic Empyrean the players create the world as they explore it with a mix of individual authority, shared authority, and random card draws. It's non-traditional in a lot of ways though, so not everyone's cup of tea. It is definitely a worthwhile example of how such a system could be built. Studying the interplay between the system mechanics, character mechanics, world-generation mechanics, and setting conceits to determine how it ticks could be enlightening.
Key to the on-the-fly world generation are the game's authority structure and the nature of the setting and characters.
Authority is shared by all players:
The nature of the setting is specific but also not particular:
The world-generation system, then, relies on the fact that authority is shared and on the nature of the setting to harness the group's creativity to build out from the starting realm. The shared authority means that small contributions build up in unexpected ways into interesting, engaging places and events that nobody needed to construct (or even could have predicted) beforehand. The nature of the setting means that there is lots of room to build anything the players can imagine (really, anything is compatible, the way the world is defined in the book) and individual players can lean on their creative strengths.
The setting also means that there are natural bounds to play, so the mode of play switches to a creative building mode only when one of those limits is deliberately crossed by the group in order to discover what's over there. It handles during-play world creation as well as between-play solo creation, depending on how ownership is apportioned for the to-be-discovered piece of the world. The conceit that the PCs are shaping the rebuilt world in their own image makes the creative play mode parallel what is happening within the game: the player creating a realm represents their PC rediscovering a lost realm and influencing it's unfolding back into reality with their own personality.
The default way of playing is very non-traditional, but it also supports a more traditional GM/players division of labour simply by giving one player ownership of more kinds of things in the world – if all new realms are owned by the "world player", then one player can craft the world to their vision while the "character players" manipulate and explore it. It also spends a few paragraphs on using the system for different genres.
It's not a generic on-the-fly world-building system by far, but it's an interesting game technology and the only one that I know of that actually works seamlessly during play to give both structured results while being flexible and who and how it's used.