How would you incorporate MWI multiverses in DND, where there are many worlds resulting from alternate possiblities. For instance, there could be a timeline where a famous wizard turned into a lich, and another timeline where he or she didn't.

Quote from: FishMeisterSupreme on April 08, 2025, 03:11:05 PMHow would you incorporate MWI multiverses in DND, where there are many worlds resulting from alternate possiblities. For instance, there could be a timeline where a famous wizard turned into a lich, and another timeline where he or she didn't.

MWI is a matter of presenting locations accessed via exotic means that happen to reuse maps and NPC sheets (plus possible alternate PCs who get to be NPCs).

I'm not even sure it's even a real scientific theory and not actually just something invented by TV execs to justify reusing sets and extras that someone with a science background glommed onto because you publish or perish.

Note for other readers who might be confused by the title - MWI is the "Many Worlds Interpretation" of quantum theory, meaning that for every random quantum event, there are different universes where each outcome happened. This usually comes up for time travel stories where one can travel to different times and also between branches.

Quote from: FishMeisterSupreme on April 08, 2025, 03:11:05 PMHow would you incorporate MWI multiverses in DND, where there are many worlds resulting from alternate possiblities. For instance, there could be a timeline where a famous wizard turned into a lich, and another timeline where he or she didn't.

I've never seen it in D&D, but there's some good resources on alternate timelines in other genres for RPGs.

GURPS Alternate Earths and GURPS Alternate Earths II present a great series of different timelines of Earth, with potential either just as a setting of their own - or a universe-jumping campaign where one goes between them.

It makes things a little science-fiction-y, but D&D has had spaceships and psionics and such from the early days -- so there's no reason one couldn't take a similar approach in D&D. The trick is coming up with interesting branching points to create different timelines to jump between.

Quote from: Chris24601 on April 08, 2025, 03:42:01 PMI'm not even sure it's even a real scientific theory and not actually just something invented by TV execs to justify reusing sets and extras that someone with a science background glommed onto because you publish or perish.

It is but it doesn't really work the way it is presented in media.  It's a way to get around some of the wonkiness in the standard Copenhagen interpretation like the collapse of the wave function.  The cat isn't in some superposition state of being both dead and alive until you look at it.  It's alive in one universe and dead in the other.  You don't know which universe you are in until you looks.  Well, more or less.  I'm far from an expert in this.

You don't.

For starters, the way media presents MWI isn't really accurate to the physics, but the truth of the matter--you can't possibly interact with any of the other universes--is inherently uninteresting because what's the point in discussing something you can't interact with?

That said, the standard comic book/ Hollywood interpretation of Many worlds multiverses make choice and consequences meaningless because all possibilities get explored, and so you have to frame the story (campaign) such that the players won't ever realize that. It also tends to devalue humanity. In many cases you can "revive" a dead character by stealing or copying their counterpart in another universe, which makes death irrelevant. Technically, these are different people, but most writers who resort to MWI have just enough of a sociopathic streak to not fully appreciate that, and it tends to encourage a similar degree of high functioning sociopathy in the consumer.

This is not to say that the trope can't work, but that it inherently requires framing the interaction between universes. You need to bridge two specific universes for a specific reason, and not let your players access any universe anywhere at any time. And chances are the players will need to know that there are limits to what universes you can access in metagame.