Doctor Strange in the Multiverse of Madness could introduce a mystical realm called Otherworld into the MCU - a theory that neatly explains several aspects of the recent trailer. "The multiverse is a concept about which we know frighteningly little," Doctor Strange cautioned Peter Parker in Spider-Man: No Way Home. As egotistical as Stephen Strange may be, even he has to admit there are limits to his knowledge - although his horizons are destined to be expanded in Doctor Strange 2. The film will apparently spin out of Spider-Man: No Way Home, with Strange unwittingly unleashing a multiverse of madness, and potentially stumbling into a realm called Otherworld as well.

The recently-released Doctor Strange 2 trailer confirmed the scale of the devastation, with entire planes of reality decaying before Strange's eyes - including what appears to be the Mirror Dimension. There are hints both Scarlet Witch and Doctor Strange will tap into dark interdimensional magic over the course of the film, with one shot showing Strange reading the Darkhold - a book of forbidden lore that, in the comics, can warp reality itself. But one of the most striking shots seems to introduce viewers to what can be loosely described as the "geography" of the multiverse, with Strange stepping through a door to a mysterious realm that comic book readers believe could be the Nexus of All Realities - and it's in ruins.

Related: No Way Home: Why Doctor Strange's Astral Spell Is So Weak Against Spider-Man

It would make sense for Doctor Strange 2 to introduce the Nexus of All Realities - but there's just one problem. The comics themselves used this term to refer to several different locations and phenomena, and readers may be assuming they're looking at one version when in fact it's another. It's actually possible Doctor Strange in the Multiverse of Madness will introduce a realm called Otherworld - and if so, it could truly transform the future of the MCU.

The Nexus Of All Realities & Otherworld Explained

X-Men Starlight Citadel

There have actually been multiple places described as the "Nexus of All Realities" in the comics. The most famous is accessed through a portal in the Florida Everglades, a place where the fabric of spacetime has been described as "exceedingly threadbare." Entering this Nexus of All Realities takes a person to a plane of existence outside reality, that serves as a sort of buffer between the dimensions and prevents them colliding; there are doorways to every other universe here. But other locations have also been called a Nexus of All Realities as well, including the Panoptichron, a crystal palace that lies at the heart of the multiverse - and appeared to be teased in Marvel's What If..? But perhaps the most interesting so-called "Nexus" is a place usually known as Otherworld.

Otherworld is a mystical plane of reality that has traditionally been treated as a representation of the collective unconsciousness of the British Isles, home of myth and legend, seat of King Arthur's throne. Recent comics have redefined Otherworld, revealing it is larger than anyone had previously thought. It is divided into the Fair and Foul Courts, and at its center is the Starlight Citadel, which lies at the heart of the multiverse itself and contains doors to every other dimension. X of Swords: Creation gave the best account of Otherworld's Starlight Citadel:

Floating high above the central diplomatic zone in Otherworld is the Starlight Citadel, physical manifestation of the epicenter of the Otherworld, where all realities intersect. If Otherworld were said to be a wheel, the Citadel would be its spoke - though it is unmoving, without it, the wheel cannot turn.

The Citadel is more than simple a beautiful monument; it is a fortress serving as the defense of the infinite doors within. Each doorway serves as passage to another reality - making the Citadel the most literal representation of the conjunction of all realities that Otherworld represents.

Related: Doctor Strange Was Evil In No Way Home: All Evidence For MCU-Breaking Theory

The Architecture In Doctor Strange 2 Could Be The Starlight Citadel

Doctor Strange 2 multiverse

The Doctor Strange 2 trailer sees the heroes step through a doorway into what viewers speculate could be the MCU's Nexus of All Realities. But the Nexus associated with the Florida Everglades - typically guarded by the Man-Thing - doesn't usually have any buildings and constructions, and the Panoptichron is noted for its entirely crystalline architecture. The structures seen in the trailer for Doctor Strange in the Multiverse of Madness are much more like the Starlight Citadel - hovering in the clouds of some mysterious realm, defying physics, and containing those typical portals that allow entry to other dimensions. The stained glass windows are reminiscent of Middle Ages architecture, which would correspond to the standard portrayal of Otherworld as tied to Arthurian lore. If this is indeed the Starlight Citadel, then its current state of disrepair indicates the multiverse truly is in a state of chaos.

The Crow In The Doctor Strange 2 Trailer Fits With Otherworld

Doctor Strange in the Multiverse of Madness Crow

The Otherworld theory also potentially accounts for one of the strangest details in the Doctor Strange 2 trailer - an ominous shot of a crow. Crows have traditionally been seen as ill omens, portents of death - likely because as carrion, they tend to flock to battlefields to tuck into the fallen. In Celtic mythology, the warrior goddess Morrighan often takes on the form of a crow, and the sight of three of these birds indicates Morrighan is watching. There are possible links between the Morrighan and the Arthurian witch Morgan Le Fay, whose mastery of magic allowed her to transform into a crow. Morgan is an established Marvel villain, the student of Merlin, and in the comics there have been occasions when she actually conquered Otherworld. She also has history with Scarlet Witch, seeking ways to use her power for herself, so she'd fit well as a villain in Doctor Strange in the Multiverse of Madness.

There have been rumors Morgan Le Fay would appear in Doctor Strange 2, so the possibility can't be ruled out. The interesting question is whether, in the MCU, Morgan Le Fay is the destroyer of Otherworld - or simply someone who has been freed by its destruction and is taking advantage of the chaos. Again, there are comic book precedents for both ideas, so Marvel could take either approach - depending on whether they envision her as a major antagonist or simply a one-and-done villain.

Marvel Has Already Been Setting Up Otherworld

Kit Harington as Dane Whitman Black Knight Gemma Chan as Sersi Eternals

Marvel has actually been subtly setting up Otherworld for some time. Eternals introduced Kit Harington as the MCU's Dane Whitman, a character who has his own mysterious ties to Otherworld. In the comics, he inherits the mantle of the Black Knight, a legacy that runs all the way back to the days of Camelot and King Arthur. The first Black Knight, Sir Percy of Scandia, was given the enchanted Ebony Blade to defend Camelot, and it has been passed down through his bloodline. Eternals seems to be taking exactly the same approach, with confirmation Camelot existed in the MCU's history and the movie ending with Whitman readying himself to take possession of the Ebony Blade in the hopes it would help him rescue his beloved Sersi.

Related: Marvel Already Ruined Doctor Strange's Multiverse Villain Reveal

That isn't even the first potential nod to Otherworld, though. During Avengers: Endgame's time travel mission, Steve Rogers eavesdropped on his beloved Peggy Carter when she served as director of SHIELD back in the 1970s. Apparently someone named "Braddock" hadn't checked in recently - and there's only one Braddock family in the comics. The Braddocks are tied to the multiverse, with many of their members recruited to the Captain Britain Corps - the sworn defenders of Otherworld, champions of the Starlight Citadel. If Doctor Strange in the Multiverse of Madness' trailer does indeed show the Starlight Citadel, then the Captain Britain Corps must have fallen.

The Destruction Of The Starlight Citadel Could Set Up The MCU's Secret Wars

Secret Wars

In the comics, writer Jonathan Hickman penned one of the most spectacular Avengers tales of all time - a multiversal apocalypse in which different universes collided. The Avengers desperately attempted to prevent the destruction of the multiverse, but they were unsuccessful, and for a brief time only a single world survived in an epic event miniseries called Secret Wars. Marvel Studios has already drawn significantly on Hickman's run - he created the Black Order, Thanos' servants in Avengers: Infinity War and Avengers: Endgame - and unsurprisingly there have been consistent rumors their current multiversal arc will lead to the MCU's Secret Wars. It's interesting to note the defeat of the Captain Britain Corps and the destruction of the Starlight Citadel was a necessary precursor to Secret Wars in the comics, because the apocalypse's orchestrators knew the powers contained there would stand in their way and try to save the multiverse.

All this means it would make sense for the Nexus of All Realities seen in Doctor Strange 2 to actually be the Starlight Citadel, the center of Otherworld, already destroyed. Not only would this perfectly indicate the scale of the destruction already being wreaked across spacetime, it would serve as perfect setup for Secret Wars - turning Doctor Strange in the Multiverse of Madness into the next step in a journey towards the ultimate multiversal Marvel adventure. Hopefully future trailers and TV spots will drop some more clues, and allow viewers to say for certain which of the various Nexuses the MCU is bringing to life.

More: Doctor Strange 2: Scarlet Witch's New Costume Has A Hidden Dark Detail

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