The diverse and profound source material is offering Marvel Studios numerous choices in constructing the future tapestry of the MCU.
The diverse and profound source material is offering Marvel Studios numerous choices in constructing the future tapestry of the MCU.
With the multiverse theme being explored in the MCU, Marvel Studios can bring forth numerous realities, many fantastical worlds onto the big screen. Alongside the quantum realm reemergence of Ant-Man in Ant-Man & the Wasp: Quantumania, MCU has taken audiences on journeys to explore various dimensions, such as the Astral Plane (Black Panther), Duat (Moon Knight), Valhalla (Thor: Love and Thunder), or the Mirror Dimension (Doctor Strange).
In the original comic source, the Marvel universe is a diverse collection of countless different worlds. The quantum realm essentially combines two spatial dimensions: the Quantum Zone and the Microverse when depicted on screen, as Marvel Studios does not hold the film rights to the Microverse. And in the future, the studio may continue to explore many other worlds to further expand the scale of its cinematic universe.
Negative Zone

Among the unexplored dimensions in the MCU, the Negative Zone arguably stands out as the most significant and frequently referenced in the source material. First introduced in the pages of Fantastic Four #51, released in 1966, the Negative Zone essentially exists as a parallel universe to our own, composed entirely of anti-matter. This inherent nature makes traversing and exploring this realm exceptionally challenging and perilous.
However, with his genius intellect, Reed Richards, the leader of the Fantastic Four, successfully devised a means of traversing to the Negative Zone. This detail could potentially support Marvel Studios' incorporation of the superhero team into the MCU in their standalone film, slated for release on February 14, 2025. The reversed polarity within the Negative Zone might grant them extraordinary superpowers; alternatively, the accelerated passage of time within could enable them to journey back to the 1960s and appear in the present day.
The Negative Zone also has connections to several other superheroes. These include Mar-Vell - the original Captain Marvel, and Rick Jones - a character with the ability to swap positions between individuals in the regular world and the Negative Zone. Marvel Studios has somewhat explored this phenomenon in the concluding segments of the Ms. Marvel series, wherein Carol Danvers and Kamala Khan inadvertently switch places while utilizing their own superpowers.
Lastly, the Negative Zone serves as the 'homeland' to many major villains in the Marvel universe who have yet to grace the big screen, such as Annihilus or Blastaar. These characters could very well become antagonists in the upcoming blockbuster featuring the Fantastic Four.
Dream Dimension

The Dream Dimension has been briefly mentioned in the Loki series but has never been fully explored within the MCU. As the name suggests, this dimension is intricately connected to the human subconscious and is regarded as a physical manifestation, a tangible form of dreams. More importantly, the Dream Dimension is the realm of Nightmare, one of Doctor Strange's most formidable adversaries in the source material.
In fact, Nightmare was once earmarked as the primary antagonist in the blockbuster Doctor Strange in the Multiverse of Madness, before Marvel Studios replaced director Scott Derrickson with 'master of horror' Sam Raimi. Although that concept didn't materialize on the silver screen, dreams still play a crucial role in this epic.
At present, it's challenging to ascertain whether Marvel Studios intends to bring the Dream Dimension to the big screen in the future. Following his multiverse adventures and inadvertently causing an incursion, Doctor Strange, along with the sorceress Clea, ventured to the Dark Dimension to rectify his mistakes. However, this implies that the upcoming blockbuster for Strange is likely to focus more on the Dark Dimension rather than any other dimension or world.
However, alongside the multiverse narrative, Marvel Studios is also gradually expanding the supernatural aspect of the MCU, with projects such as Moon Knight, Werewolf by Night, and the upcoming Blade. The Dream Dimension still stands a chance of being explored in such blockbusters, or even in the second season of the Loki series, slated for release this summer.
Nexus of All Realities

Theoretically, the Nexus of All Realities has been explored in the MCU through the animated series What If...? This is the convergence point of all realities in the multiverse, also where Uatu the Watcher observes all events across timelines. Previously, the Nexus of All Realities was hinted at in the blockbuster Thor: The Dark World through the conjecture of Dr. Erik Selvig when he explained the Convergence phenomenon.
However, in comic book canon, the Nexus has significant ties to Man-Thing, a character newly introduced into the MCU through the project Werewolf by Night. To prevent individuals from exploiting the Nexus of All Realities and traveling anywhere in the multiverse, Man-Thing has become the guardian of this nexus.
The Nexus of All Realities, shrouded in extraordinary power, remains one of Marvel's greatest mysteries to date. Dr. Ted Sallis was the first to discover this place after a car accident in the swamp. Blood mixed with dark magic transformed Sallis into a creature named Man-Thing, simultaneously activating the gateway to the Nexus of All Realities.
Limbo

In the Marvel comic universe, there are numerous dimensions and realities known as Limbo. The Loki series also introduced a similar world when Loki and Sylvie journeyed to a kingdom beyond the time stream of He Who Remains.
Limbo is also a demonic dimension associated with an X-Men member, Illyana Rasputin, also known as Magik. This mutant's ability to teleport instantly allows easy access to and from Limbo. As a child, Rasputin was kidnapped and raised by Belasco, the ruler of that dark realm, before she rebelled and escaped the clutches of the demon's prison. Magik appeared in the 'New Mutants' bomb X-Men franchise produced by 20th Century Fox (now 20th Century Studios), portrayed by Anya Taylor-Joy.
However, with the current events in the MCU, Limbo is likely not to be explored by Marvel Studios until the multiverse storyline concludes. X-Men are poised to be the central superhero group of the MCU post-phase 6. Hence, it's not surprising if Limbo is brought to the big screen only after a few years and directly tied to Marvel's roster of mutants, similar to the source material.
Olympus

The role of the gods in the MCU has been elevated to new heights through the new projects of phase 4, especially Thor: Love and Thunder. In search of allies against the godslayer Gorr, Thor sought out Omnipotent City, considered the home of many gods ruled by Zeus.
More importantly, Thor: Love and Thunder brought Hercules to the big screen, portrayed by Brett Goldstein. This implies that Olympus appearing in the MCU is only a matter of time. Similar to Asgard, Olympus is a small dimension and the homeland of the Greek gods, with connections to the underworld ruled by Hades. It seems that each god from different cultures will exist in different dimensions, such as Celestial Heliopolis for the Ennead, the Egyptian gods who appeared in the series Moon Knight.
Avalon

Another example of the gods' dimension is Otherworld and the kingdom of Avalon. This is the home of the Tuatha de Danaan, the Celtic gods, and has a close relationship with the multiverse. Similar to Nexus, Avalon is also the nexus of many (but not all) different realities. Therefore, this place fits perfectly into the multiverse storyline that the MCU is exploring.
Just like Captain Carter in the animated series What If…?, Captain Britain is also a member of the Captain Britain Corps, a coalition of various superhero variants, tasked with protecting the multiverse. In the original, Brian Braddock became Captain Avalon, the guardian deity of this kingdom, and passed on the title of Captain Britain to Betsy Braddock.
There have been numerous rumors regarding Marvel Studios' plans to introduce Captain Britain into the MCU. However, to date, this superhero has yet to appear on the big screen.
Mojoworld

Mojoworld is a kingdom outside of space and the homeland of the Spineless Ones - strange creatures with yellow skin, no hair, each hand with only four fingers, and most notably, no spine. One of the most prominent members of the Spineless Ones is Mojo, who has clashed with the X-Men multiple times in Marvel comics.
As mentioned, the X-Men will be central characters in the future of the MCU. Therefore, it's not unlikely that Mojoworld will also be explored by Marvel Studios after the conclusion of the multiverse storyline.