I have no idea what I'm doing but want to do it anyway
Well, it's a start.
So, my first thoughts for how to organize the whole thing is there's a primary Hub, which connects either directly to various worlds, or to secondary hubs, which then connect to worlds. Not sure which is better, could do a combo. Thoughts? Maybe options for temporary or permanent links to be made in one world to connect to others?
In all honesty, I'm not a huge fan of the "hub" idea. Linking a bunch of worlds sounds neat. But what is the hub's
purpose? If it's just to connect everything, everything could be connected on its own. If it's meant to control or gate interactions in some way, then what are the advantages of doing that through one central hub as opposed to individually? And in all cases, what are the hub's qualities? Is it a grim, desolate realm of the dead that must be trekked through to reach your destination? A cyberpunk cafe where everyone's immortal but you can still have hilarious brawls demolishing everything? A grand palace of glass ruled by a fairy king gatekeeper whose favor is needed to access each world?
Linking the worlds directly, through places, actions, and/or times of power, is more flexible in all those regards. Which isn't always a good thing, of course, but I get the feeling you should
start with "they're linked somehow, portals or something. Wormholes. Books, meditation, whatever, ask that particular GM" and then move into the hub idea if you see a particular use for it.
I'm thinking that the links between world/hub should be closed from the getgo and unactivated until someone in the world opens it on purpose or by accident. Or maybe the world just happens to already have an open gateway from times past. Again, purely up to the GM, I have no bloody idea how this will work right now sooooo thoughts?
I'd go a step further and say that "the links" are more akin to "the weapons" than "the plot." That is, they're out there, but the exact method of acquiring/making/finding them varies by world and particular player situation. Again, largely in line with my notion that the games should be built around themselves first and then linked, not built to slot into place.
Worlds and Physics and Magic: I'm thinking denizens of a given world follow that worlds physics even when not in that world. Magic would probably need to be acquired from their homeworld unless they were compatible with a separate world. Again, not sure how it will work. Thoughts?
So as an example, suppose there are three worlds. World X is a medieval fantasy world where people have souls, magic exists and knights in shining armor slay dragons. World Y is a cyberpunk world where everyone has become an AI, corporate soldiers fight in slow motion using firearms and augmentation is the norm. World Z is a dark fantasy world where minds are kept coherent simply because of some natural law where unpredictable systems have a tendency to remain unpredictable, magic does not exist and all combat is ranged. Now, suppose someone from World X had the ability to imbue swords with layered hives of infant souls via magic. Their ability may be anchored as "The ability to imbue [common close ranged military weapons] with a layered hive of infant [essence of an individual] via [feature that allows individuals to be powerful]."
So, if they moved to World Y, it becomes "The ability to imbue shotguns with a layered hive of infant AIs via a specialized augmentation." so upon entering the world, they would lose their magic and instead find that they have a cybernetic enhancement already built into them that serves a similar purpose. If they moved to World Z, it becomes "The ability to imbue hands with a layered hive of metastable unpredictability by channeling the minds of dead infants through sheer force of will and infamy." so upon entering the world, they would lose their magic and instead gain such an imposing atmosphere about the that they can harness the power of dead babies through sheer willpower.
Suppose a person from World Z had learned to 'read' people to predict their actions. In World Y, it would instead manifest as kinetic prediction software installed in their brain, so they'd lose the ability to predict what people will do, but instead become able to predict trajectories and movements. In World X, it would turn into full-blown divination where it becomes less controlled and relevant but can cover far greater spans of time and in greater detail.
Or you could fit everything's
mechanical effect to the destination world's physics and theme. Someone brings a suneating void horror larger than the star it intends to devour into a mundane slice of life setting involving talking animals? It comes out with the size and abilities of a grumpy cat, because that's how things work in that world. Plasma rifles are akin to crossbows, cooking skills grant combat bonuses, the ability to punch down mountains grants +2 on door kicking checks, whatever's equivalently reasonable in that world without changing what it is too much.
And obviously, this raises all sorts of questions and room for interpretation, but that'd be true even between different GMs, let alone different campaigns, worlds, or systems. If you're doing this, you're probably in it largely for the linkage lulz.
Worldbuilding. GM's have control of worldbuilding for their respective worlds. Player characters likely can do some stuff also, probs best for the GM to say what's okay to add and what's not for the players. Quality matters. Preferably stable worlds, but if someone feels like doing an unstable one, go ahead, be good for a plotpoint if they try invading another for resources. Not entirely sure here. Thoughts?
Canon Quality Control: For things that affect multiple worlds or a Hub, all affected GM's and maybe players should talk about it. With other people adding input if needed, if you want to do a major plotpoint that will affect another world, talk to the GM of that world first. If you're a player and you want to overthrow a monarch in the world you're on, talk to your GM first so he/she know's what's going on and can set up the plotline for that. Think this is decent, buuut thoughts?
I'm a big fan of indirect effects, but I'm not sure how applicable that is here. I mean, everyone from one game just sort of piling into someone else's doesn't sound
that interesting, right? They kind of need a reason to be there in the first place, so I suspect some level of GM cooperation to get players into or at least affected by one world or another might be mandatory. Maybe they could keep that as a central idea when trying to come up with plots/adventures/challenges/stuff for their game? "Okay, it'd be nice if I could get them into The World Of Terror somehow, because I want to watch them all die... artifact! Go get it, Temple of Bones, nothing to worry about. Old man will teleport you, have three days, late to the beacon and you don't get out, the usual."
Or, as I briefly mentioned before talking about something else, you could go for indirect effects. Maybe the players in one world don't really want to go to another, but they're suffering odd consequences because of it. Maybe some enemy type is spilling across planar boundaries, and they can empower the defenders of that world by reactivating The Beacons. So they're not traipsing about the multiverse
personally, but they've got some fairly roundabout but solid reasons to care about the events and qualities of another world.
But yes, overall I don't think there's any getting around GM cooperation being necessary for world bridging. I mean, I guess you could do some kind of "false body" avatar thing where interlopers are completely handed over to the home GM who interprets and handles them however and then hands them back to the original GM who interprets and handles the results. That way if, for whatever reason, all the players die screaming but GM B's running a low-fatality, high-reward game, GM B can just say "Well, you tried, dream ended poorly, you grabbed a bunch of loot for managing to survive three rounds."
Of course, that'd disconnect them even more than they already would be, which might or might not be great.
I honestly do not think that this could happen with different rulesets, the compatibility issues would be too important. Definite, universal rules, should be applied to keep some sort of internal coherence.
After all, if multiple GMs are agreeing to connect ther creations, then they must make some concessions.
This is basically the issue I have with all this talk of standardization: Just participating in this thing requires a certain level of concession. How many people are you going to be able to get willing to use the exact same rulesets as each other on top of doing the link thing in the first place? In my opinion, the games are going to have to be able to stand on their own in addition to standing together, which means they're going to have to be games the GMs themselves want to run. Worrying too much about the linkage might endanger the things you were hoping to link to.