An inter-related set of story-worlds that are all stories that are being told within the other worlds. Or, at least, one story world that constantly refers to another story world.
Players start with multiple character sheets. Each is designed for a different setting: one might take place in an ancient, mythical time, one during the Renaissance, another during the early 21st Century, and one in the distant future (I'm using different chronological periods of our own world, but this is not necessary). In fact, having this many different settings could end up being too chaotic. I'll focus on only two instead. For example, Renaissance and mythical time.
Each of these settings is controlled by a different player. The players are all well aware in advance of the different worlds, who GMs which, and who the players play in each world.
So, say, the first story starts in the Renaissance. The Renaissance story continues for awhile - maybe a few hours, maybe a session or two, but at some point one of the characters says that a myth of the ancient world is relevant to their current situation, and so the player's jump to the ancient past and begin living out this myth. This might go on for awhile, and eventually either the GM of the mythic past turns back into the character in the Renaissance narrating - and then they once again start playing their game in the Renaissance.
Obviously problems could happen:
What if the ancient myth doesn't really tie into the current situation? - This would be a criticism against the literary merit of this particular chronicle, but still might be fun to play.
What if the two GMs constantly try to force switching narrative roles when the other doesn't want to? This could be a more serious problem. Really, this kind of gaming would require two mature and diplomatic GMs to work properly. Related:
What if one GM doesn't want to relinquish control? Same answer as above.
This game would likely be far more situationalist than narrative or gamist based. If played at all, it would probably need to be played for the love of exploring different settings. This would both be a limitation and something to embrace.
Another - not problem per se - but style the game would have to embrace is impromptu storytelling. Because each GM may not know much before a switch occurs they'd have to know how to continue their part of the game at anytime.
Also, related to this style of game, or another form of it, is having characters who are virtually immortal: Highlanders, Vampires, et cetera and having them flashback to past centuries. With this, I've been wanting to do this with Requiem for Rome and Vampire: The Requiem to jump from the Roman eras with kindred who've recently awoken from torpor in modern nights.
Thoughts on this? Anyone try any of these styles of play? Anyone recommend any games that are especially open to this style of play?