Reality Travel - Who's Best, Who Fails?

[Florian]

@Quertus:

The PF, specifically the extended Golarion cosmology is a bit different:
Basically, all "game worlds", even those of different game systems, are part of the Dark Tapestry (aka Prima Material Plane). There're "darker" and "lighter" regions that will define how close or far away the regions of the Dark Tapestry are to the underlying building blocks of the cosmos, aka Inner and Outer planes, which will define if magic is available and to what extend.
It´s also very specific that there're no "right" or "wrong" means to access magic, treating the topic closer to how oWoD Mages or Shadowrun handles their traditions. For example, the 3.5E magic system is called "Sin Magic" and would work alongside the PF magic systems without a fuzz, same as with sphere magic. Occult is as definitely non-magic power source that even works in the "darkest" regions of the Dark Tapestry and would include things like CoC-style "magic". Alhazred is shown as a "Theoretical Wizard" who has the basic knowledge put down, but can´t use anything but occult rituals while on Earth.

[Earthwalker]

Sadness.

[snip] Talking about TORG character

Sounds like a strong candidate.

What are their mechanics for how they impose their reality on others?

Well imposing your reality on others in the game is what the bad guys are doing and it involves connecting your reality with theres and devices to stabilize it. Normally laid out in 60 mile triangles (from what I remember) anyone normal in the area converts to the new reality.

Those aren't the people I am putting forward for reality hoping tho.

Possibility rated characters (the PC) have the ability to keep their own reality and carry it with them (they get a reality skill). So even if you are in a world where magic doesn't work, you can still use your spells for you.

Add into the list things artifacts of certain realities that are hard points for that reality.

Realities in game had ratings on... Tech, spiritual, social and magic. They also had hard coded rules. PC used either their own rating and rules or could dip and use the ratings / rules of the reality they were in.

It was a game system about crashing realities so of course its going to handle reality skippers well.

I also loved it back in the day, just for the idea of how it worked.

[caden_varn]

OK - in Torg, if you confront a threat from another reality and stand against it, instead of cowering or running away, your connection to your own reality might reinforce, making you possibility-rated (or a stormer, or storm knight, due to the intense storms that form on the borders between realities). This allows you to consciously manipulate reality to increase your chances of success (ie roll extra dice on skill checks), decrease damage taken, and take your personal axioms around with you (technological, magical, spiritual & social). So even if a realm does not allow magic, you can try to override this to use magic anyway. It does have some drawbacks - you run the risk of disconnecting from your reality, which forces you to work at the current realms axioms until you can reconnect (normally not too difficult, although you either need to be in your core reality, or have the tool that caused you to disconnect in hand. This can be tricky if, as happened to one of my group, you disconnect throwing a grenade into the pacific ocean).
You also get protection against being converted to a different reality. Someone without a reinforced connection who enters a different reality or is in an area invaded be a new reality is at risk of being converted to the new reality. This will rewrite memories & skills, so you may forget how to use a gun or drive a car, but suddenly be able to ride a horse and shoot a bow. If you get converted a second time, you are likely to die, unless someone has been able to reinfuse you with a little possibility energy (not an easy process).
Possibility-rated people from different realities can attempt to convert each other to their reality, stripping them of their possibility energy in the process, but they cannot do this to normals - their link to their reality is just to weak for the stormer to latch onto. A stormer can expend some energy to temporarily create a bubble where only their axioms will work, which may have the same effect.

But if you really want to inflict your reality on others, you need a darkness device. Each reality has exactly one - a sentient malevolent artifact that seeks a powerful warlord-type to bond with & invade other realities to drain their possibility energy. The device gives its wielder a number of abilities, including the ability to cross or send others into different realities, either subtly, or via a maelstrom bridge which brings their reality (and armies) over to the invaded reality.

Earth has a particularly strong reality in the game, so 7 other realms go together to invade - The Gaunt man invaded Indonesia with his Victorian horror reality, Orrorsh. Dr Mobius invaded Egypt with his silver age of superheroes reality, forming the Nile Empire. Aysle invaded the UK & Scandinavia with a high fantasy reality. Their friends, a medieval inquisition society invaded France, but due to complex stuff, picked up cyberpunk technology during the invasion (the darkness device liked it, basically), becoming the Cyberpapacy.
North America lost a lot of territory, along with it's president & VP to the Living Land, a low-tech dinosaurs & cavemen reality. Japan got invaded by a reality very close to earth axioms, a bit lower in magic & spirit, a little higher in tech. A scheming superspies reality called Marketplace.
Reality 7 got shafted by Marketplace, who helped the Russians remove their stelae (which allow the invading reality to withstand the pressure of the invaded reality), so when they dropped their maelstrom bridge, Earth's stronger reality just rolled straight up it and caused a lot of chaos. They reappeared later, invading LA mostly to screw over Marketplace that was trying to expand their.. A high tech, magic & spirit realm populated mostly by cyberdemons and their human slaves.

It's a fun, if often chaotic game, once you understand & can correct for the balnaces inherent in the system

[caden_varn]

Well imposing your reality on others in the game is what the bad guys are doing and it involves connecting your reality with theres and devices to stabilize it. Normally laid out in 60 mile triangles (from what I remember) anyone normal in the area converts to the new reality.

Those aren't the people I am putting forward for reality hoping tho.

Possibility rated characters (the PC) have the ability to keep their own reality and carry it with them (they get a reality skill). So even if you are in a world where magic doesn't work, you can still use your spells for you.

Add into the list things artifacts of certain realities that are hard points for that reality.

Realities in game had ratings on... Tech, spiritual, social and magic. They also had hard coded rules. PC used either their own rating and rules or could dip and use the ratings / rules of the reality they were in.

It was a game system about crashing realities so of course its going to handle reality skippers well.

I also loved it back in the day, just for the idea of how it worked.

And not sure how I managed to miss this post which summarises it better than I managed. But I think the main takeaway is - for the best chance of surviving (and conquering) a different realm, be a High Lord! Then you just need to survive your darkness device. And best of luck to you doing that...

[Quertus]

Well, no, in-story that's a bit like saying that their abilities would be useless in any reality which doesn't exist. In-story, ALL realities are reflections of Amber (or of the Courts of Chaos, though apparently most Amberites don't even know that the Courts exist during the first series of books--but that could be a matter of an unreliable narrator).

But, from what you said about every world - there's worlds small enough that one can just look around, and say "nope", from which I can only conclude that there exist worlds, including, say, my D&D world, that is not a world of Amber.

As I imagine any system's / setting's assertion that all worlds belong to it will fail for similar reasons. Any fact that they assert about all worlds, one need only provide a single counter example to disprove their claim.

Your destination's qualities matter as much as your traveler's qualities.

Absolutely true.

You can't really answer what happens when incompatible things collide without some form of author fiat... or a destination world specifically designed to answer those questions. Beyond that, there's the issue of many stories having multiverses of their own, not simply a single universe... for travel outside of that, we need both some sort of term for multiverse of multiverses (omniverse?) and some agreed-upon ground rules for how multiverses interact, leading us back to fiat.

We are accustomed to fiat of either "it just works" or "rebuild it in the new system". I am asking, what if we take the hard road, attempt to remove as much fiat as possible, and instead focus on the underlying mechanics, asking, "how should these interact?".

So if you have a suitable destination world, you can talk about the subject. If not... it's really up to fiat.

No, that misses the point. I'm explicitly looking at unsuitable destination worlds. I'm asking how should reality travel fail.

I don't think this question can be answered. I mean, you have a few, which come from books/media that assume all realities follow the rules of their books, but beyond that, there is not answer.

Actually, those are the non-answer.

If we assume all powers work in all universes,

Nope. Totally not assuming that.

Asking, "how do these powers actually work?", followed by, "what assumptions about the universe are required for them to work?", followed by "which universes have such requirements?".

For example, D&D magic requires the weave. In any reality without the weave, D&D Wizards are just smart guys in pajamas. In realities without matter, they'll likely respond as though exposed to a vacuum. Etc etc.

@Quertus:

The PF, specifically the extended Golarion cosmology is a bit different:
Basically, all "game worlds", even those of different game systems, are part of the Dark Tapestry (aka Prima Material Plane).

And we're back to my suspicion about any author who tries to make assertions about all game worlds, but ok...

There're "darker" and "lighter" regions that will define how close or far away the regions of the Dark Tapestry are to the underlying building blocks of the cosmos, aka Inner and Outer planes, which will define if magic is available and to what extend.

How far pieces of the prime material are... From the inner and outer planes? Well, that really turns D&D cosmology on its head for me.

And... this somehow determines if (D&D) magic is available? Please, explain why PF ties (non-divine) magic to access to the inner and outer planes.

It´s also very specific that there're no "right" or "wrong" means to access magic, treating the topic closer to how oWoD Mages or Shadowrun handles their traditions. For example, the 3.5E magic system is called "Sin Magic" and would work alongside the PF magic systems without a fuzz, same as with sphere magic. Occult is as definitely non-magic power source that even works in the "darkest" regions of the Dark Tapestry and would include things like CoC-style "magic". Alhazred is shown as a "Theoretical Wizard" who has the basic knowledge put down, but can´t use anything but occult rituals while on Earth.

So, PF tries to assert that, if any magic works, all magic works? Since there are worlds where that is not true, PF sounds like it fails at claiming all worlds under its umbrella.

Although, I must say, I like its inclusive umbrella. Just to make sure I'm hearing you right, by RAW, my 2e Wild Mage would function just fine in PF? Or, a PF nobleman could, by RAW, have a Trompe L’oeil of a 2e D&D Wizard, who could have a Simulacrum of a... Chaos Troll Cultist of Tzeentch... And said Simulacrum's magic should work just fine? If I ever play PF, I think I know what my character will look like.

Well imposing your reality on others in the game is what the bad guys are doing and it involves connecting your reality with theres and devices to stabilize it. Normally laid out in 60 mile triangles (from what I remember) anyone normal in the area converts to the new reality.

These devices would fail on any worlds which actively disable technology (although it sounds like the villains probably have the "skill" to ignore that...)

Those aren't the people I am putting forward for reality hoping tho.

Possibility rated characters (the PC) have the ability to keep their own reality and carry it with them (they get a reality skill). So even if you are in a world where magic doesn't work, you can still use your spells for you.

Add into the list things artifacts of certain realities that are hard points for that reality.

Realities in game had ratings on... Tech, spiritual, social and magic. They also had hard coded rules. PC used either their own rating and rules or could dip and use the ratings / rules of the reality they were in.

It was a game system about crashing realities so of course its going to handle reality skippers well.

I also loved it back in the day, just for the idea of how it worked.

So... the PCs have the ability to impose their rules of reality "because"?

It's a skill. A skill that anyone can use? A skill that lets you use magic (and technology and...) even in worlds where it normally wouldn't work? Can anyone use this skill? Can you only use it to impose your home world, or the rules of any worlds? Can you use it to disable things that wouldn't work in your home world - "That gun can't hurt me - I'm too primitive for it."?

It sounds like a fun system to play in, but I'm not certain that it will answer quotations about the underlying mechanics to my satisfaction.

[Quertus]

Ah. So, in Torg, there's a trigger event which changes a person, at which point they can learn the skill. Ok. It seems that the wisest course of action is to expose the entirety of your population to this trigger event (via staged "invasions" by a friendly reality).

[Earthwalker]

And not sure how I managed to miss this post which summarises it better than I managed. But I think the main takeaway is - for the best chance of surviving (and conquering) a different realm, be a High Lord! Then you just need to survive your darkness device. And best of luck to you doing that...

Kinda glad you gave a longer description because...

So... the PCs have the ability to impose their rules of reality "because"?

It's a skill. A skill that anyone can use? A skill that lets you use magic (and technology and...) even in worlds where it normally wouldn't work? Can anyone use this skill? Can you only use it to impose your home world, or the rules of any worlds? Can you use it to disable things that wouldn't work in your home world - "That gun can't hurt me - I'm too primitive for it."?

It sounds like a fun system to play in, but I'm not certain that it will answer quotations about the underlying mechanics to my satisfaction.

In essence there are in game rules for how you become possibility rated and how you get the skill. The skill is about keeping your own reality in the face of a new one being imposed on you not really about imposing it on others (High Lords and Darkness devices aside)

Lets try to answer those questions.

Its a skill only possibility rated people can use (they need to have contacted multiple realities)
It lets you use your own reality's rules / axioms not the one you are in.
It does allot you to impose your own world on YOURSELF.

Its more I'm a primitive I cant use a gun. More than, that gun wont work on me. If you are on core earth guns work fine on primitives, if the living land (the primitive reality) over rights core earth. Then guns aren't going to work (That's how they invade)
You can use reality to get close to things and stop them working, you can create a reality bubble around you of your home reality. (A primitive standing next to a nuclear bomb and reality bubbling will stop the bomb.

In conclusion its a game about realities clashing. It gives you rules for all this works it doesn't spend a lot of time discussion the why and the how.

It does it so you can have people from different realities running around being heroes.

[Earthwalker]

Ah. So, in Torg, there's a trigger event which changes a person, at which point they can learn the skill. Ok. It seems that the wisest course of action is to expose the entirety of your population to this trigger event (via staged "invasions" by a friendly reality).

The artifacts that do this are called darkness devices for a reason.
They want their reality to grow.

"Friendly" reality is not a thing.

You will make some possibility rated people the vast majority of the people will just change to the new reality.
Getting people back isn't as simple as turning off the new reality. Again for game reason destroying invading reality will just kill the people that changed (as they cant take the change back) you can make it possible by converting them to your cause and then changing the reality... (Its kind of like Earthdawn in that you have to do heroic things and sway the population to your side... there were rules)

[caden_varn]

In theory you could, but the only people who could stage such an invasion are high lords with their darkness devices, which are sentient, malevolent and exist only to absorb the possibilityenergy of other cosms. Good luck finding a friendly one. You'd be better off becoming high lord of your realm and invading somewhere else. You don't need to be in your own reality to become possibility-rated IIRC, so your troops will have as much chance of transforming as the defenders.

[Heliomance]

How has no-one mentioned MtG Planeswalkers yet? Again, this is explicitly their powerset.

[Nifft]

In terms of who travels best, maybe it'd be a Planeswalker from Magic: the Gathering?

How has no-one mentioned MtG Planeswalkers yet?

We did.

But please do go into more detail if you know any MtG lore about magic-dead or mana-dead planes.

[Arbane]

But, from what you said about every world - there's worlds small enough that one can just look around, and say "nope", from which I can only conclude that there exist worlds, including, say, my D&D world, that is not a world of Amber.

As I imagine any system's / setting's assertion that all worlds belong to it will fail for similar reasons. Any fact that they assert about all worlds, one need only provide a single counter example to disprove their claim.

That's kind of a useless statement, since by definition, a fictional character is a character in their own story, and a game character is a character in their own game. If they travel somewhere new, it is, by definition, part of their story or game.

(Outside of fanfic, anyway, but that has NO RULES.)

We are accustomed to fiat of either "it just works" or "rebuild it in the new system". I am asking, what if we take the hard road, attempt to remove as much fiat as possible, and instead focus on the underlying mechanics, asking, "how should these interact?".

That way lies madness, tears, and Trekkin's Gary Stu GM. But I repeat myself.

No, that misses the point. I'm explicitly looking at unsuitable destination worlds. I'm asking how should reality travel fail.

Ravenloft?
Being in a singular reality without any alternates to visit?
Arrival being instantly fatal?


And to answer someone else: Exalted are made of matter, it's just that in Creation matter is made of Essence, not atoms.

[Zombimode]

For example, D&D magic requires the weave.

You keep mentioning this. The Weave is a specific part of the Forgotten Realms. There is no Weave in Eberron, Greyhawk, Mystara, Freeport, Rokugan, Dark Sun, Lankhmar or Dragonlance.
You could argue that some of these settings are part of the greater Planescape cosmology so that they are techincally in the same (meta-)setting as the FR. But that still leaves out things like Eberron and probably countless homebrew settings that are NOT part of Planescape.

[Lapak]

But, from what you said about every world - there's worlds small enough that one can just look around, and say "nope", from which I can only conclude that there exist worlds, including, say, my D&D world, that is not a world of Amber.

I have no idea how you reach that conclusion from that starting point. Because some shadow worlds are small, there are worlds that are not shadows? I am missing a link in that logic chain.

Amusingly, since our real Earth on which the book was written is called out as a shadow of Amber, your D&D world is explicitly a part of it... as a D&D campaign at the very least. ;-)

[Quertus]

You keep mentioning this. The Weave is a specific part of the Forgotten Realms. There is no Weave in Eberron, Greyhawk, Mystara, Freeport, Rokugan, Dark Sun, Lankhmar or Dragonlance.
You could argue that some of these settings are part of the greater Planescape cosmology so that they are techincally in the same (meta-)setting as the FR. But that still leaves out things like Eberron and probably countless homebrew settings that are NOT part of Planescape.

I am using "the weave" as a shorthand for "whatever the **** D&D mages need in order to cast their spells". The term "the weave" has the advantage of being a named entity with clear influence over the availability (and stability) of magic. Now, back in my day, many tables dubbed this needful thing the "elemental plane of magic". Which is an equally obfuscating term, given how afaik it isn't directly related to planar geography. Apparently, PF begs to differ.

I have no idea how you reach that conclusion from that starting point. Because some shadow worlds are small, there are worlds that are not shadows? I am missing a link in that logic chain.

Amusingly, since our real Earth on which the book was written is called out as a shadow of Amber, your D&D world is explicitly a part of it... as a D&D campaign at the very least. ;-)

Perhaps I have misunderstood you, but I took you to say that, because of the history of Amber, there was a property that was shared by all worlds of Amber. Yet, there exist worlds small enough to actively perceive that they lack this property, thereby proving the existence of worlds that are not worlds of Amber.

Not that that terribly contradicts the beliefs of Amber as I understood you to explain them, mind, as those worlds might simply be beyond the courts of chaos.

[Nifft]

I am using "the weave" as a shorthand for "whatever the **** D&D mages need in order to cast their spells". The term "the weave" has the advantage of being a named entity with clear influence over the availability (and stability) of magic.

It does have some semantic disadvantages, though, such as the fact that the Weave is an artificial layer imposed by one specific god to prevent mortal mages from achieving high-valence effects and thus prevent a repeat of That Netherese Foolishness™.

In other words, you're using it to communicate something which you think is generic, but it's also communicating a bunch of other things because it's NOT generic -- it's setting-specific and comes with significant baggage.

[Max_Killjoy]

@Quertus:

The PF, specifically the extended Golarion cosmology is a bit different:
Basically, all "game worlds", even those of different game systems, are part of the Dark Tapestry (aka Prima Material Plane). There're "darker" and "lighter" regions that will define how close or far away the regions of the Dark Tapestry are to the underlying building blocks of the cosmos, aka Inner and Outer planes, which will define if magic is available and to what extend.
It´s also very specific that there're no "right" or "wrong" means to access magic, treating the topic closer to how oWoD Mages or Shadowrun handles their traditions. For example, the 3.5E magic system is called "Sin Magic" and would work alongside the PF magic systems without a fuzz, same as with sphere magic. Occult is as definitely non-magic power source that even works in the "darkest" regions of the Dark Tapestry and would include things like CoC-style "magic". Alhazred is shown as a "Theoretical Wizard" who has the basic knowledge put down, but can´t use anything but occult rituals while on Earth.

That's rather presumptuous of Pathfinder... "we're laying a sort of claim to every setting / secondary world ever, and at least this one bit if "no really it's not magic" magic works even if the setting is specifically one with no magic or occult or anything of the sort".

[Khedrac]

But, from what you said about every world - there's worlds small enough that one can just look around, and say "nope", from which I can only conclude that there exist worlds, including, say, my D&D world, that is not a world of Amber.

And this is why the answer is always author's fiat - whatever the person running the world crossing makes the rules to be determines who is best off.

As I imagine any system's / setting's assertion that all worlds belong to it will fail for similar reasons. Any fact that they assert about all worlds, one need only provide a single counter example to disprove their claim.

Except that is usually pretty much impossible to do. Take the Amber example - presumably you are saying that because there is no black road running through the world we are not a shadow of Amber? So how do you know that there is no black road running through the world? Even requiring it to be on earth this hits two problems:
The only date we really have tied for the event is that it is after the 1970s. Since time does not run at the same speed in all worlds the black road may still be in our future. (Yes, the characters go back to "Earth", but given their travvelling abilities it does not have to be the same earth so it is not a safe reference to say the road must have happened.)
Secondly, the road appears in every world, this does not mean it is any world for any great distance - would you really know if there was a few hundred yards of a black road somewhere on this planet that had not been there before (bear in mind, it could be running along the bottom of the sea)?
Result - your "disproof" of us being a shadow of Amber (assuming I understood it correctly) is not actually provable.

Update - now I think I see I was wrong above - you are saying that there is pocket worlds small enough that one can see no road? Well 2 answer here - first is "are there?" - they may just be insertions into another world and not count as separate; and second - again is time - the road was a temporary discrete event - it may not have happened yet or have happened in the distant past of the hypothetical "small world".

We are accustomed to fiat of either "it just works" or "rebuild it in the new system". I am asking, what if we take the hard road, attempt to remove as much fiat as possible, and instead focus on the underlying mechanics, asking, "how should these interact?".

The moment you mix the creations of multiple world-building authors there are no underlying mechanics.
In fact, this can apply with a single author.
For example, the late great Diana Wynne Jones:
In some of her early books (very much childrens' books) the world is one of a number of linked worlds that form a series. When someone from one world travels to another in their series their duplicate in that series cannot co-exist with them and so gets "bounced" into the next world of the series, and the duplicate in that world gets bounced etc. all the way round to the last duplicate being pulled in to fill their place.
In one of her later books (aimed more at adults) when a group visit a nearby world everyone who has a duplicate in that world dies because you cannot have two copies of the same person alive in the world at the same time (the worlds were more closely related that they knew - about half the group died on entry).

The only "common underlying mechanic" is that the worlds support the telling of a story that makes sense to us as human readers.

No, that misses the point. I'm explicitly looking at unsuitable destination worlds. I'm asking how should reality travel fail.

Now this is a very different question - and one we can work with - I have just provided an example answer above.

How far pieces of the prime material are... From the inner and outer planes? Well, that really turns D&D cosmology on its head for me.

Less than one Plank unit of distance. They are not any distance away, they are just different.
Actually the part that should blow your mind is the Ethereal plane - it has to be at least 4 dimensional for geography:
It is coterminous with the Prime plane - so every point on the prime plane has a matching point in the ("surface") Ethereal (so if you enter the etheral you can travel up, down, left, right etc. and be moving relative to the prime plane). Yet at the same time, one can travel through the (deep) ethereal to reach the inner planes - and it's a relatively short journey - so it cannot be in the same direction as anything in the prime plane...

And... this somehow determines if (D&D) magic is available? Please, explain why PF ties (non-divine) magic to access to the inner and outer planes.

Because a Paizo author wanted to claim this.

I am using "the weave" as a shorthand for "whatever the **** D&D mages need in order to cast their spells". The term "the weave" has the advantage of being a named entity with clear influence over the availability (and stability) of magic. Now, back in my day, many tables dubbed this needful thing the "elemental plane of magic". Which is an equally obfuscating term, given how afaik it isn't directly related to planar geography. Apparently, PF begs to differ.

Different D&D worlds have made different claims at different times about what it takes to cast magic - one cannot generalise on this.

Perhaps I have misunderstood you, but I took you to say that, because of the history of Amber, there was a property that was shared by all worlds of Amber. Yet, there exist worlds small enough to actively perceive that they lack this property, thereby proving the existence of worlds that are not worlds of Amber.

Not that that terribly contradicts the beliefs of Amber as I understood you to explain them, mind, as those worlds might simply be beyond the courts of chaos.

Actually for me there's a bigger problem - a road passing through infinite worlds has to be infinitely long, yet forces are travelling down the road to attack Amber and they are not taking infinitely long to do so...
We don't know that there are worlds small emough to be able to tell that they are not part of Amber, unless you as author say so - again this is author fiat.

I would suggest giving up this discussion as pretty pointless, instead go back to the question about why inter-universe/multiverse travel might fail and we can have fun coming up with lost of different reasons.

[Lapak]

Perhaps I have misunderstood you, but I took you to say that, because of the history of Amber, there was a property that was shared by all worlds of Amber. Yet, there exist worlds small enough to actively perceive that they lack this property, thereby proving the existence of worlds that are not worlds of Amber.

Not that that terribly contradicts the beliefs of Amber as I understood you to explain them, mind, as those worlds might simply be beyond the courts of chaos.

I think you may be confusing me with someone else, because I wasn't the one talking about Amber before this (it's been a decade or more since I've read the books) - I just could not figure out your reasoning there.

[Quertus]

It does have some semantic disadvantages, though, such as the fact that the Weave is an artificial layer imposed by one specific god to prevent mortal mages from achieving high-valence effects and thus prevent a repeat of That Netherese Foolishness™.

In other words, you're using it to communicate something which you think is generic, but it's also communicating a bunch of other things because it's NOT generic -- it's setting-specific and comes with significant baggage.

Sigh. This is like the whole Martial Mundane Muggle fiasco. Got a suggestion for a word with no inherent baggage?

That's rather presumptuous of Pathfinder... "we're laying a sort of claim to every setting / secondary world ever, and at least this one bit if "no really it's not magic" magic works even if the setting is specifically one with no magic or occult or anything of the sort".

Point. Note to self: I need to create a setting that makes lots of these assumptions of "this works in every realm", so that I can play things as fun as the 2e Wild Mage in every game.

And this is why the answer is always author's fiat - whatever the person running the world crossing makes the rules to be determines who is best off.

Sigh. This is as true and as meaningless as "the GM has rule 0". That is, there are rules and logic for how various realities work - or, at least, there should be.

The author shouldn't have to fiat an answer. The rules should cover it.

presumably you are saying that because there is no black road running through the world we are not a shadow of Amber?

would you really know if there was a few hundred yards of a black road somewhere on this planet that had not been there before (bear in mind, it could be running along the bottom of the sea)?
Result - your "disproof" of us being a shadow of Amber (assuming I understood it correctly) is not actually provable.

Update - now I think I see I was wrong above - you are saying that there is pocket worlds small enough that one can see no road? Well 2 answer here - first is "are there?" - they may just be insertions into another world and not count as separate; and second - again is time - the road was a temporary discrete event - it may not have happened yet or have happened in the distant past of the hypothetical "small world".

Yes, numerous settings have worlds this small. Timing, however, is an issue.

The moment you mix the creations of multiple world-building authors there are no underlying mechanics.

Each author had their mechanics. The question is, how well do they telegraph them? Can we follow the rules to predict an outcome?

In fact, this can apply with a single author.
For example, the late great Diana Wynne Jones:
In some of her early books (very much childrens' books) the world is one of a number of linked worlds that form a series. When someone from one world travels to another in their series their duplicate in that series cannot co-exist with them and so gets "bounced" into the next world of the series, and the duplicate in that world gets bounced etc. all the way round to the last duplicate being pulled in to fill their place.
In one of her later books (aimed more at adults) when a group visit a nearby world everyone who has a duplicate in that world dies because you cannot have two copies of the same person alive in the world at the same time (the worlds were more closely related that they knew - about half the group died on entry).

The only "common underlying mechanic" is that the worlds support the telling of a story that makes sense to us as human readers.

Yes, those two sets of world had different underlying mechanics. That's kinda my point.

Now, what happens when they interact?

Less than one Plank unit of distance. They are not any distance away, they are just different.
Actually the part that should blow your mind is the Ethereal plane - it has to be at least 4 dimensional for geography:
It is coterminous with the Prime plane - so every point on the prime plane has a matching point in the ("surface") Ethereal (so if you enter the etheral you can travel up, down, left, right etc. and be moving relative to the prime plane). Yet at the same time, one can travel through the (deep) ethereal to reach the inner planes - and it's a relatively short journey - so it cannot be in the same direction as anything in the prime plane...

This is old hat. I've been dealing in 5 dimensions since original D&D, and dealing with planar layers and recalculating plusses on items and divine caster level based on plans away from source plane since... 2e, IIRC.

It's the idea of tying access to magic to that mess that had me scratching my head as to just how they think magic works.

Because a Paizo author wanted to claim this.

Sigh. Not the kind of answer I wanted, but probably the truth of it!

Different D&D worlds have made different claims at different times about what it takes to cast magic - one cannot generalise on this.

Really? Sadness. Do you have specifics?

I would suggest giving up this discussion as pretty pointless, instead go back to the question about why inter-universe/multiverse travel might fail and we can have fun coming up with lost of different reasons.

What can I say, I like rules, and the interactions thereof.

[PhoenixPhyre]

The problem, Quertus, is that the mechanics can't interact, and any attempt to reason about that is purple monkey dishwashers. They're all true inside their own sphere but undefined outside that region of concept space. That's pure nasal demon territory.

But giving it a shot anyway, any person who depends on external power or anything beyond the most basic technology (fire, muscle power, etc) is going to have it rough. There's no guarantee that the laws of physics are even slightly similar at the level they'd need to be for advanced tech. You can't even guarantee that chemical reactions work--my setting doesn't even have atoms or molecules. It's all soul stuff, aspected in different ways and in different levels of condensation.

[Max_Killjoy]

The problem, Quertus, is that the mechanics can't interact, and any attempt to reason about that is purple monkey dishwashers. They're all true inside their own sphere but undefined outside that region of concept space. That's pure nasal demon territory.

But giving it a shot anyway, any person who depends on external power or anything beyond the most basic technology (fire, muscle power, etc) is going to have it rough. There's no guarantee that the laws of physics are even slightly similar at the level they'd need to be for advanced tech. You can't even guarantee that chemical reactions work--my setting doesn't even have atoms or molecules. It's all soul stuff, aspected in different ways and in different levels of condensation.

Indeed.

There's no guarantee that an individual won't drop over dead, turn to dust, or explode at the speed of light, when they get to a new "reality". There's no guarantee that the food will be edible or the air breathable. There's no guarantee that the magic or science or whatever that got them there, will function there and allow them to move on. Any "inter-reality" trip is a potential one-way trap or death-sentence.

[NichG]

If you want to construct a globally self-consistent multiverse capable of containing all settings, you're going to have to start at a much more abstract level than things like 'physics' or 'magic'.

You need some equivalent of 'all things which can be specified sufficiently to distinguish them from nonexistence, exist'. Even Multiversal laws like 'anything expressible as math' or 'anything that could be run on a Turing machine' are probably too narrow to cover all of existing human fiction. So you're left with, roughly, if an author could possibly think about it clearly enough to convey the idea of it, it exists somewhere.

Any guarantees you want to get beyond that are going to be statistical ones rather than absolute ones. If it's the multiverse of human fiction, worlds that kill everything on arrival will be less common than worlds where the reality travelers can continue the story. If it's the multiverse of mathematical expressions, you'd better not leave home because the anthropic principle is probably the only reason you're in a life-supporting universe to begin with and 'stepping to the world next door' has about as much chance if supporting your life as 'stepping to a random point in space'.

So if we have a meta-anthropic principle such as 'this story takes place in a multiverse in which reality walking is a thing', that probably gives the most information one can hope to get about power interaction. I think that roughly reciprocates the intuition that if a character needs a certain power to exist, that power is more likely to extend in some form across universes. So something like 'biology' is likely to keep working, but also if it's a metasetting in which undead can planeswalk, it's likely that undeath translates in some fashion as well.

[Quertus]

But giving it a shot anyway, any person who depends on external power or anything beyond the most basic technology (fire, muscle power, etc) is going to have it rough. There's no guarantee that the laws of physics are even slightly similar at the level they'd need to be for advanced tech. You can't even guarantee that chemical reactions work--my setting doesn't even have atoms or molecules. It's all soul stuff, aspected in different ways and in different levels of condensation.

Yes, external power sources are a problem. So, perhaps, a good way to look at my question is in no small part to evaluate which realities' characters often depend on external power sources.

Now, "laws of physics" is an interesting one. No matter? Well, so what, my gun is still made of matter. Oh, your air isn't? Well, I guess my gunpowder can't combust... and I guess I can't breathe start suffocating. But a NASA rocket would work just fine in a no matter world.

There's other possible ramifications, but I think we all need to get on the same page on the simple stuff before I go there.

Indeed.

There's no guarantee that an individual won't drop over dead, turn to dust, or explode at the speed of light, when they get to a new "reality". There's no guarantee that the food will be edible or the air breathable. There's no guarantee that the magic or science or whatever that got them there, will function there and allow them to move on. Any "inter-reality" trip is a potential one-way trap or death-sentence.

True.

Perhaps my question is more... hmmm... given the set of works of fiction containing "relatable characters", what problems can we foresee with their interaction in what, to them, are habitable spaces?

If you want to construct a globally self-consistent multiverse capable of containing all settings,

I'm not sure if that's really what I want to do.

I want to define various assumptions of settings, like "made of matter" or D&D's magic's reliance on a particular planar geography.

I want to note when these assumptions fail, like technology actively fails in WoD Dark Ages.

I want to see just how realistically characters could travel to supposedly habitable portions of other realities, and just how bad that would be for some of them.

If it's the multiverse of mathematical expressions, you'd better not leave home because the anthropic principle is probably the only reason you're in a life-supporting universe to begin with and 'stepping to the world next door' has about as much chance if supporting your life as 'stepping to a random point in space'.

This particular issue is something that the author of a RIFTS-like homebrew discussed with me. Yes, clearly, random plane travel is as suicidal as random teleportation.

So if we have a meta-anthropic principle such as 'this story takes place in a multiverse in which reality walking is a thing', that probably gives the most information one can hope to get about power interaction. I think that roughly reciprocates the intuition that if a character needs a certain power to exist, that power is more likely to extend in some form across universes. So something like 'biology' is likely to keep working, but also if it's a metasetting in which undead can planeswalk, it's likely that undeath translates in some fashion as well.

Again, this feels like the opposite of what I want. I don't want to impose rules, I want to evaluate fail states from rules interactions.

[NichG]

I'm not sure if that's really what I want to do.

I want to define various assumptions of settings, like "made of matter" or D&D's magic's reliance on a particular planar geography.

I want to note when these assumptions fail, like technology actively fails in WoD Dark Ages.

I want to see just how realistically characters could travel to supposedly habitable portions of other realities, and just how bad that would be for some of them.

This particular issue is something that the author of a RIFTS-like homebrew discussed with me. Yes, clearly, random plane travel is as suicidal as random teleportation.

Again, this feels like the opposite of what I want. I don't want to impose rules, I want to evaluate fail states from rules interactions.

The thing is, those assumptions aren't part of the closure that constitutes a given setting. The thing about magic, the weave, etc in D&D is an example of this.

To put it more explicitly, if I'm running D&D, there's nothing intrinsic to D&D that tells me how to construct the answer to the question 'can magic still function here?' because from the point of view of the D&D rules and settings, there are multiple equally good explanations for how D&D magic works. That kind of freedom is why you can take the D&D system and then proceed to make one world where magic is just an omnipresent thing (e.g. Greyhawk/generic D&D setting #3), an adjacent world where magic is the blessing of a specific goddess who portions it out freely and the only difference between that and divine powers is that the goddess isn't picky about who gets to receive the blessing (e.g. Faerun), and a third setting where magic is the captured and expended life-force of living things (Dark Sun).

All three takes on magic are very different in terms of the 'physics' of magic, but they're all consistent with the same overlying D&D mechanics. Yet a character from Faerun going anywhere else definitely becomes unable to use arcane spells, while a character from Greyhawk might or might not become unable to do so, and a character from Dark Sun could presumably do so as long as they find some plants to drain or use the appropriate obsidian foci to drain animals (which might have to be Athasian plants and animals, but might not).

So in order to prefer one interpretation over another, you need some other source of information. All we have left to provide that information is to look at 'global' consistency and plausibility. That is to say, if we assume that we're telling a story in which someone uses arcane magic to step from reality A which has arcane magic to reality B which, on the face of it, does not seem to, then we've introduced additional information in the form of the premise that the arcane magic of reality A was able to actually affect reality B - so saying 'arcane magic absolutely does not exist at all in reality B' is an excluded possibility based entirely upon the fact that we're talking about a story in which someone actually does manage to make that reality travel event occur.

To put it another way, 'you can get there from here' would itself be an informative statement. You could have a reality B which totally denies all magic in any shape or form, but in that case one couldn't logically be able to use magic to travel there either. So a reality walker is, a priori, less likely to get stuck than one might think in a totally arbitrary set of universes, since any universe they make it to must be compatible enough to at the very least allow the reality walker's trick to work to inject stuff into that universe.

That's the kind of thing I mean by a meta-anthropic principle.

If you don't rely on that sort of filter, I don't think its possible to uniquely answer questions such as 'are D&D characters made of matter?'. They may be, or may not be; either could be self-consistent and consistent with the rules and setting information.

[Khedrac]

Sigh. This is as true and as meaningless as "the GM has rule 0". That is, there are rules and logic for how various realities work - or, at least, there should be.

Why?
Seriously, why should there be any underlying logic to how two different fantasy worlds work? The only underlying logic there can be is that the world supports the telling of a story we find interesting.

Consider The Simpsons TV series - there is an episode where Homer goes to "the real world" and the key difference is that the real world is 3 dimensional not 2 dimensional. Pretty much anything that is supposed to have 3 or more dimensions is likely to suffer catastrophic failure when inserted into a world with two of fewer (note, Gold Box D&D as a setting allows plans with between 1 and 5 dimensions, magic required 4 to work under these rules).

The author shouldn't have to fiat an answer. The rules should cover it.

On the contrary - the author has to be the one defining the answer - this is now their ficticious creation.

Each author had their mechanics. The question is, how well do they telegraph them? Can we follow the rules to predict an outcome?

Yes, those two sets of world had different underlying mechanics. That's kinda my point.

Now, what happens when they interact?

And this is our point - it is up to the person writing the interation to define how it works. Yes, when authors have laid out some of the underlying logic of their universe then there are conclusions people can draw, but don't expect those conclusions to match (just look at the RAW debates in the 3.5 D&D subforum).

It's the idea of tying access to magic to that mess that had me scratching my head as to just how they think magic works.

In a lot of cases they haven't thought that far - "it's magic - it works" is all they need.

What can I say, I like rules, and the interactions thereof.

Fine - then I suggest you start trying to write guidelines for how you would make them interact, you are asking us to define the impossible.

Now, "laws of physics" is an interesting one. No matter? Well, so what, my gun is still made of matter. Oh, your air isn't? Well, I guess my gunpowder can't combust... and I guess I can't breathe start suffocating. But a NASA rocket would work just fine in a no matter world.

Why should the Nasa rocket continue to work? If cordite won't work then it is quite likely that the rocket fuel won't either. Different physical laws means that chemical reactions can stop working - so it is actualy "can't breathe" (or even "can't live") rather than simply "start suffocating".

Incidentally "made of matter" is way too broad a category:
Earth - matter is made of elements made of sub-atomic particles.
Some settings - matter is made of elements
Most D&D settings - matter is made of the 4 (?) elements (let's not worry about para- and quasi- elmental planes, or the extra elemets the oriental rules add - bother Companion D&D then has the elements interact differently so we'll ignore that too).
Glorantha - matter is probably made of runes.

I want to define various assumptions of settings, like "made of matter" or D&D's magic's reliance on a particular planar geography.

I want to note when these assumptions fail, like technology actively fails in WoD Dark Ages.

Then do this, rather than ask "what are the rules for interaction?"

Yes, clearly, random plane travel is as suicidal as random teleportation.

Obligatory link.

Again, this feels like the opposite of what I want. I don't want to impose rules, I want to evaluate fail states from rules interactions.

Unfortunately there are no rules for you to evaluate unless you write them.

[Fiery Diamond]

We are accustomed to fiat of either "it just works" or "rebuild it in the new system". I am asking, what if we take the hard road, attempt to remove as much fiat as possible, and instead focus on the underlying mechanics, asking, "how should these interact?".

Well, the short answer to that question is "they shouldn't." If you don't have a destination world that explicitly permits specific things, the question of "how should these incompatible realities interact without authorial fiat" is as nonsensical and meaningless as "what should the properties of a square circle be?" This renders the whole exercise moot.

[Quertus]

one world where magic is just an omnipresent thing (e.g. Greyhawk/generic D&D setting #3), an adjacent world where magic is the blessing of a specific goddess who portions it out freely and the only difference between that and divine powers is that the goddess isn't picky about who gets to receive the blessing (e.g. Faerun), and a third setting where magic is the captured and expended life-force of living things (Dark Sun).

All three takes on magic are very different in terms of the 'physics' of magic, but they're all consistent with the same overlying D&D mechanics.

Harumph. You may be right, but I stubbornly don't want to believe this. I want to believe that D&D isn't just an interface level, but also specifies underlying mechanics. I want to believe that Defilers found a life-draining shortcut, but otherwise use the same magic as every other D&D Wizard.

To put it another way, 'you can get there from here' would itself be an informative statement. You could have a reality B which totally denies all magic in any shape or form, but in that case one couldn't logically be able to use magic to travel there either.

I hadn't been assuming that they were getting there under their own power. Like how Batman was a good example of someone who would work well on various realities. Yes, if you can get there under your own power, it kinda implies that your power has meaning there.

Why?
Seriously, why should there be any underlying logic to how two different fantasy worlds work?

Wrong question. "Why should there be any underlying logic as to how one fantasy world works?" is the correct question.

The fact that two worlds need not share underlying logic is the crux of the issue.

But, to get to the point of comparing them, one needs first to look at their underlying logic individually.

On the contrary - the author has to be the one defining the answer - this is now their ficticious creation.

When I'm handed someone else's code as a black box, I don't magically gain the ability to alter it. I don't get to define how Windows operates just because I wrote code for it.

Why should the Nasa rocket continue to work? If cordite won't work then it is quite likely that the rocket fuel won't either. Different physical laws means that chemical reactions can stop working - so it is actualy "can't breathe" (or even "can't live") rather than simply "start suffocating".

Hmmm... I hadn't consisted that. Thank you. I need to check my assumptions here.

Hmmm... I have been working under the "no hand waving, no conversations" banner. If you're made of matter, you remain made of matter, even if you travel to a realm of ideas. Thus, a NASA rocket (that does not require other matter to interact with) would continue to function (whereas a gun, which requires air for combustion would not).

However, if reality is the operating system, then code from an incompatible reality simply wouldn't run.

Best I can figure, I must be assuming either a) that the multiverse is the OS, and, thus, all code runs fine on all worlds without causing the world to crash, or (the equivalent?) b) anything a given reality can't process defaults to being run by the multiverse.

I'll need to look into my assumptions further.

Well, the short answer to that question is "they shouldn't." If you don't have a destination world that explicitly permits specific things, the question of "how should these incompatible realities interact without authorial fiat" is as nonsensical and meaningless as "what should the properties of a square circle be?" This renders the whole exercise moot.

Why do you believe in an explicit permissions model?

[Nifft]

Sigh. This is like the whole Martial Mundane Muggle fiasco. Got a suggestion for a word with no inherent baggage?

Magical Factor was the 1e MotP term that I posted about last page.

That ought to do the job.

To put it another way, 'you can get there from here' would itself be an informative statement. You could have a reality B which totally denies all magic in any shape or form, but in that case one couldn't logically be able to use magic to travel there either. So a reality walker is, a priori, less likely to get stuck than one might think in a totally arbitrary set of universes, since any universe they make it to must be compatible enough to at the very least allow the reality walker's trick to work to inject stuff into that universe.

That's the kind of thing I mean by a meta-anthropic principle.

I endorse this thinking.

[dps]

Harumph. You may be right, but I stubbornly don't want to believe this. I want to believe that D&D isn't just an interface level, but also specifies underlying mechanics.

Well, you can believe whatever you want to believe, but that doesn't make it true. There was a quote about DnD from an old book that reviewed various games that said, "Even in theory, D&D isn't a game but a game system. In practice, it's not even that--it's a system for designing a game system". To your point, DnD, at least as far as the written rules is concerned, doesn't particularly care why magic works, but rather how magic works--and even that can be different in different settings, whether published or homebrew.