Need help linking all known D&D settings

[Mongobear]

In the process of planning out a plot for a 5e campaign, which will involve a BBEG which can transition between all known D&D settings, such as Faerun, Eberron, Dragonlance, etc and also involves the various Planeshift X races.

The basic premise is that through centuries of influence, both directly and through minions, the BBEG has thrown off the balance of the Outer Planes so badly, that they begin falling apart, and causing rifts on the various Material Planes. Which if left unchecked, eventually tear the entire plane into the void between planes.

My issue, is two-fold, for one, how do I bring PCs together from everywhere in the multiverse? I was thinking Sigil, however I am not very familiar with it, alternatively I could just make up my own equivalent to Sigil, and ignore any canonical features.

Secondly, what can I actually use as the BBEG? Beings native to the Outer Planes have just as much to lose as they'd gain. Mortals likely wouldn't be able to discover the existence of the multiverse to travel there.

Perhaps something Old God/Far Realms related? Like the Eldrazi from the various MtG sets? Since the MtG stuff will be allowed, I considered a Planeswalkers, such as Nicol Bolas, but I absolutely hate the idea of how much he has been used.

Maybe a Diety went rogue, and decided to try and ruin all existence, but again, if I used Sigil, I'm pretty sure there are rules to prevent Dieties from influencing realms they're not native to. Tharizdun comes to mind, or possibly one of my own creation?

Any tips, suggestions, or links to information would be much appreciated.

[sktarq]

Have you considered Spelljammer (https://nerdarchy.com/5e-dd-in-space-with-spelljammer-is-back/)?

[Hugh Mann]

How to get the party together-

All of the party members could have died, but due to the multiverse being out of balance things went wrong. Instead of going to their religion's proper afterlife they ended up in a random one of your choosing.

Alternatively they could go to the World Serpent's Inn. Its like Sigil, but smaller. In short it is an inn that iis bigger on the inside than the outside and it can show up anywhere in the multiverse but only for a limited amount of time. The party could just walk by accident, or be drawn in on purpose.

BBEG-

I suppose it depends on how high you want the power level of the campaign to be.

If you want a high cosmic sort of thing, you could try Tharizdun. All it really wants to do is destroy the multiverse.

Alternatively you could pull one of the elder evils from 3.5 over to 5e; personally I think the ones from Lords of Madness sound more threatening than the ones stated in Elder Evils (the book). All of those guys tend to be reality warping creatures that hate the multiverse. Here are some examples:

From Book of Elder Evils- Rangorra, a fragment of the plane of life breaking off and trying to "heal" the universe. Atropus, a moon sized undead that wants to kill everything. Pandorrym a physical manifestation of oblivion that wants to kill all gods. and a bunch of other less cool things
From Lords of Madness- Bolothamogg, a force of existence that protects the Far Realms from the corruption of the core multiverse. Shothotugg, a creature that eats planets across the multiverse in order to warp the laws of reality. And some other less cool ones.



If you want something lower than CR 20, you could throw some aberrations at them. Aboleths hate all gods for destroying their empire at the beginning of time, so they might want to try to restore the multiverse to its original state (ie what it was before gods showed up). Alternatively you could throw mind flayers at the problem, their lore suggests that they are the remnants of a powerful cosmic empire that came from a different reality and/or future, so they could just try bring their empire to the multiverse.

If you want something less conventional, you could say that the current state of the multiverse is incorrect and that Primus (a god of law) or some other lawful creatures want to set the multiverse back to its intended design. Such creatures could be inevitables, modrons, or even angels if they believe the original state of things was better.

[Hugh Mann]

There is another group that could be a BBEG, the Ancient Baatorians.

They are poorly defines and very rarely referred to. They are a race of creatures that lived in Hell before the Devils took it over, but they are completely unrelated to them. Currently they live trapped underneath the the 9 Layers of Hell, and presumably cannot escape unless there are massive shifts in the planescape.

Ad&D lore states that most of the Baatorians have transcended physical form, and are immensely powerful. The few Baatorians that have been shown throughout the past editions of D&D tend to have strange powers and are almost unkillable. One Baatorian from 3.5, a retconned version of Zargon the Returner, was literally immortal since he could revive 1d4 days after its body was destroyed and had the power to make it rain slime all across whatever planet it was on. Another Baatorian from AD&D could only be killed with a wish spell and had the unique ability to be able to remove the "lightedness" from anything that was near it (as far as I can tell, it mean that anything near it was permanently turned invisible, including terrain. As of now there are no Baatorian stats for 5e

You could have a free Baatorian, or one of their sympathizers, try to rearrange the multiverse so that they can escape.

[Mongobear]

Liking some of the suggestions, but not sure any single one is perfect quite yet.

I like the idea of the Elder Evils, I loved that book, and never really got to use it back in 3.X.

An original idea I had was tied to Sigil, and the Lady of Pain. Somewhere I the Outlands, the 'corpse' of an equally powerful being awakens and begins destroying the multiverse via the connection to Sigil.

The big twist, is that this being is the original creator of Sigil, who was working with the LoP at the beginning of time, he was the Architect, she the Caretaker, but the project drove them both slightly mad, and she betrayed and killed him.

I don't know how much this conflicts with established lore of Sigil or Planechase, I never played during that era.

[Mechalich]

Liking some of the suggestions, but not sure any single one is perfect quite yet.

I like the idea of the Elder Evils, I loved that book, and never really got to use it back in 3.X.

An original idea I had was tied to Sigil, and the Lady of Pain. Somewhere I the Outlands, the 'corpse' of an equally powerful being awakens and begins destroying the multiverse via the connection to Sigil.

The big twist, is that this being is the original creator of Sigil, who was working with the LoP at the beginning of time, he was the Architect, she the Caretaker, but the project drove them both slightly mad, and she betrayed and killed him.

I don't know how much this conflicts with established lore of Sigil or Planechase, I never played during that era.

A lot.

The thing about the Lady of Pain is that she is a living setting mechanic, not actually a character. She's there to break some rules via authorial fiat to allow Sigil to exist as an independent location catering primarily to mortals that bypasses almost all the standard planar passageway security measures she doesn't actually do anything and her backstory is deliberately vague. You aren't supposed to use her for well, anything, she's just there as a (complex) part of the scenery.

Anyway, one option for a BBEG I'd put forward are the Ethergaunts (not that I'm biased (http://www.oocities.org/ripvanwormer/ethergaunts.html) or anything). They hate not only all deities but the very concept of faith itself, and they aren't native to the Outer Planes at all, so their destruction wouldn't bother them.

[Hugh Mann]

Liking some of the suggestions, but not sure any single one is perfect quite yet.

I like the idea of the Elder Evils, I loved that book, and never really got to use it back in 3.X.

An original idea I had was tied to Sigil, and the Lady of Pain. Somewhere I the Outlands, the 'corpse' of an equally powerful being awakens and begins destroying the multiverse via the connection to Sigil.

The big twist, is that this being is the original creator of Sigil, who was working with the LoP at the beginning of time, he was the Architect, she the Caretaker, but the project drove them both slightly mad, and she betrayed and killed him.

I don't know how much this conflicts with established lore of Sigil or Planechase, I never played during that era.

Well, there is precedence for stuff in Sigil affecting the rest of the planescape. If I recall, in the D&D canon Vecna invaded Sigil and that somehow changed the planescape from its AD&D version to its 3.0 version.

There is nothing that says that you have to run the Lady of Pain like a setting mechanic. The concern is that if you give her too many human qualities then she really isn’t the Lady of Pain anymore.

As an alternative to her being driven insane, you could have the Lady of Pain working exactly as her creator intended. The Architect could have made an unthinking unfeeling automatic city defense system in the shape of a woman that designed to keep Sigil safe from outsiders. But the Architect went a bit mad and went to go back and change fundamental aspects of Sigil, something that the LoP was designed to prevent.

[redwizard007]

What about using the mists of Ravenloft rather than a Sigil style city? That could tie into your BBEG as well. Let's say (insert great old one of your choice) was breaking into the outer planes from the far realm. The mists snatched him into the demiplane of dread, that may be it's intended purpose after all. Now his power has begun to corrupt Ravenloft. The mists are striking out randomly. Chunks of the planes are being ripped from reality. Some end up in Ravenloft. Some end up merging with another plane. Its chaos.

The campaign could involve mcguffin hunts all over the planes and various prime worlds culminating in a trip to Ravenloft, or the PCs could find a way to reliably enter and leave Ravenloft allowing them multiple forays to address problems in different domains while not becoming a Ravenloft exclusive campaign. Maybe they ride chunks of prime worlds into or out of Ravenloft. Tons of options here.

BTW:
Ebron
Dragonlance
Forgotten Realms
+Kara-tur, al-qadim, the horde, malatra,and maztica
Dark Sun
Pelinore
Ravenloft
Mahasarpa
Planescape
Spelljammer
Greyhawk
Birthright
Mystara
+Hollow world, savage coast, and thunder rift
Jakandor
Lankhmar
Rokugan
Wilderlands of High Fantasy
Blackmoor
Council of Wyrms
Kingdoms of Kalamar
Dragon Fist
Ghostwalk
Ravnica
And I believe there was an official Warcraft game licensed for D&D

[Bohandas]

Look up the old Spelljammer setting. Its premise is that every one of the classic campaign worlds occupies a different bubble of space on the same material plane.

[ngilop]

Look up the old Spelljammer setting. Its premise is that every one of the classic campaign worlds occupies a different bubble of space on the same material plane.

If you want to include Sigil and the Lady of Pain, there was that adventure that involved Vecna (Die Vecna, Die!) Read it over and glean some ideas from it.

[Mechalich]

If you want to include Sigil and the Lady of Pain, there was that adventure that involved Vecna (Die Vecna, Die!) Read it over and glean some ideas from it.

That adventure is widely considered to be one of the worst D&D modules ever written. I'd suggest looking almost anywhere else first.