The Cosmic Underpinnings of Ravnica as a Setting for Both Magic and D&D

Both Magic The Gathering and Dungeons & Dragons use the idea of a multiverse to connect their various settings.

I have no idea if this is still canon, but Magic actually has (or at least had) a name for its multiverse, which was called Dominia. Dominaria, the original setting of the game, was special because it was at the center of that multiverse, its name meaning "Song of Dominia."

D&D is flexible, but while they have suggestions on how to come up with your own Outer Planes (I'm sort of waffling between whether my setting's outer planes are entirely separate from the standard ones or if they're connected,) generally the idea is that there's a prime material plane that is the relatively mundane reality most player characters would be from, and then there's a succession of more and more alien planes moving outward until you get to the Far Realm, which is where the rules of reality, including the dichotomies of good and evil, law and chaos break down.

While Magic certainly has its odd locations, there's actually no real hierarchy to its planes. Each plane is a world with its own rules. Indeed, many of these planes don't really have gods, per se. Or one could argue that the true gods of Dominia are actually the abstract colors of magic, representing the conflicting philosophies and methods that then contend with each other on the planes themselves (Magic does have its own equivalent of the Far Realm, called the Blind Eternities, which is a space outside the multiverse where Magic has no colors, and from which the cosmic horror creatures called the Eldrazi hail.)

These are both pretty compelling ways to structure a multiverse (I'll confess that I like the nuance of Magic's five colors better, but that could also be because I first played Magic when I was eight and I first played D&D when I was twenty-nine.)

We don't know what the Guildmaster's Guide to Ravnica is going to be like, exactly. What little has been talked about is that they're going to have players choose guilds in place of backgrounds, and there's apparently a kind of flow-chart questionnaire to determine which guild players characters should choose. They also suggest letting players choose their guilds and then developing a story in which they rise to oppose an adversary that they would all have reason to fight against. (Already I have some character concepts: Dimir Illusion Wizard or College of Whispers Bard, Orzhov Death Cleric, Izzet Storm Sorcerer.)

What I really want to know, however, is to what extent this marks Ravnica's induction as an official D&D setting.

I suppose that the fact of the matter is that they're publishing a physical book as part of the 5th Edition line, so you don't really get more official than that.

But if we go all Planescape/Spelljammer, can players from other settings arrive on Ravnica? Does Asmodeus or Pelor get to interact with the guilds, and does Rakdos go back to the Abyss if we kill him?

Obviously the real answer to any D&D question is "does the DM allow it?" But I'm really curious to see the way that Wizards treats this in terms of marketing. Are they calling attention to the fact that the Ravnica setting has been around in Magic for the last thirteen years or so, and that it's a kind of odd man out for D&D? Or does Ravnica join Dark Sun, Greyhawk, Ravenloft, and Eberron as one of the canonical, official settings for D&D?

I realize it's all sort of much ado about nothing, as once again, it's really about what flies at your table. But I'm still really curious to see how the book turns out.