Multiverse (Marvel Comics)
Within Marvel Comics, most tales take place within the fictional Marvel Universe, which in turn is part of a larger multiverse. Starting with issues of Captain Britain, the main continuity in which most Marvel storylines take place was designated Earth-616, and the multiverse was established as being protected by Merlyn. Each universe has a Captain Britain designated to protect its version of the British Isles. These protectors are collectively known as the Captain Britain Corps. This numerical notation was continued in the series Excalibur and other titles. Each universe of the Multiverse in Marvel also appears to be defended by a Sorcerer Supreme at nearly all times, appointed by the mystic trinity of Vishanti to defend the world against threats primarily magical in nature from within and beyond and bearing the Eye of Agamotto.
Later on, many writers would utilize and reshape the multiverse in titles such as Exiles, X-Men, and Ultimate Fantastic Four. New universes would also spin out of storylines involving time traveling characters such as Rachel Summers, Cable, and Bishop, as their actions rendered their home times alternate timelines.
The Multiverse is the collection of alternate universes that share a universal hierarchy. A large variety of these universes were originated from another due to a major decision on the part of a character. Some can seem to be taking place in the past or future due to differences in how time passes in each universe. Often, new universes are born due to time traveling, another name for these new universes is an "alternate timeline". Earth-616 is the established main universe where the majority of Marvel books take place.
Nature of the Multiverse
According to Forge, mutants living on these alternate Earths have lost their powers due to M-Day, as stated in "Endangered Species", however, this mass depowering has not been seen in any of Marvel's current alternate reality publications such as Exiles, the Ultimate titles, Amazing Spider-Girl, the Marvel Adventures titles or GeNext, though it is possible that the issue of time may be related to their exclusion. This was apparently retconned during the "X-Men: Messiah Complex" storyline, where Forge stated that all mutants in possible future timelines were depowered, not in parallel universes. This, in addition to A.R.M.O.R.'s observation that Lyra arrived from an alternate reality indicates that the topology of the Marvel multiverse is based on new realities branching off from key nodes of a timeline instead of strictly parallel dimensions.
Not every alternate reality is an entire independent universe, but instead maintain a parasitic relationship to a parent reality. Others can exist outside the multiversal structure altogether.
- Counter-Earth (Heroes Reborn): A pocket dimension where Franklin Richards stored many of Earth's superheroes after the events surrounding the appearance of Onslaught. Doom saved Counter-Earth from the unstable pocket dimension, and placed it in an alternate orbit of the Earth-616 on the other side of the sun.
- The Hill: A dangerous pocket dimension used by Mikhail Rasputin after flooding the Morlock tunnels. Rasputin brought all Morlocks to The Hill to raise them in a survival of the fittest mentality. In this dimension time runs several times faster. While in Earth-616 only 1 or 2 years passed more than ten years passed in the Hill. Marrow and the other Gene Nation members grew up in this dimension.
- The Microverse: Originally, many microverses existed within the Marvel Multiverse. The most commonly visited is the one containing the regions known as Sub-Atomica and the Micronauts Homeworld.
- The Mojoverse: A dimension where all beings are addicted to gladiator-like television programs. Ruled by Mojo and home to Spiral, Longshot and the X-Babies.
- The Negative Zone: Mostly uninhabited, it is a universe parallel to Earth's with many similarities. One major difference is all matter in the Negative Zone is negatively charged. Negative Zone Prison Alpha is located here. Also the home of Blastaar and Annihilus.
- Otherplace: Also known as "Limbo" or "Demonic Limbo", A magical dimension of demons which were historically ruled by Belasco and was primarily featured in X-Men comics.
- The Void: A pocket dimension that exists inside Shaman's medicine bag.
- The Soul Gem: A pocket dimension that exists inside the green infinity gem.
- Avalon: Also known as Otherworld, this realm is an access point to the entire Marvel multiverse utilized by the Captain Britain Corps. Also home to the Celtic Gods and King Arthur.
- The Darkforce Dimension: This dimension also includes but is not limited to Spotworld as used by the supervillain the Spot and the brimstone dimension as used by Nightcrawler.
- Limbo: Also known as "True Limbo" or "Temporal Limbo", Outside of time historically ruled by Immortus and the location to which Rom the Spaceknight banished the Dire Wraiths.
- The Panoptichron: Home base of the reality-hopping Exiles, structurally dissimilar but functionally similar to Avalon.
A Universe/continuity is a single reality, such as Earth-616, the mainstream Marvel Universe/Continuity. In Marvel Comics, the concept of a continuity is not the same as "dimension" or "universe"; for example, characters like Mephisto and Dormammu hail from alternate dimensions and the Celestials from another galaxy, but they all nevertheless belong to Universe-616. A continuity should also not be confused with an imprint; for example, while the titles of some imprints, such as Ultimate Marvel, take place in a different continuity, some or all publications in other imprints, such as Epic Comics, MAX, and Marvel UK, take place within the Earth-616 continuity. Note that in context the Marvel Universe is sometimes used to refer to the Marvel Multiverse, and sometimes used to refer to the Earth-616 continuity.
A Multiverse is the collection of alternate universes, with a similar nature and a universal hierarchy. The Marvel multiverse contains the universe that holds Earth-616, most of the What If? universes, as well as the vast number of the alternate Marvel Universe Earths.
The original term and concept were coined by Michael Moorcock for his "Eternal Champion" sequence. The lead characters from Moorcock's work are obviously the inspiration for the Captain Britain Corps.
A Megaverse is the collection of alternate multiverses, which do not necessarily need to have similar natures and universal hierarchies. The term was posited in the 21st century edition of the Official Handbook of the Marvel Universe.
Known alternate universes
As stated above, nearly every imprint, timeline and appearances in other media have its own separate universe. Most of these have been cataloged by Marvel Comics in many publications, being most notable the Official Handbook of the Marvel Universe: Alternate Universes. The numerical designations for these are rarely revealed outside of reference works such as the Official Handbook of the Marvel Universe: Alternate Universes 2005. A.R.M.O.R. and Project Pegasus however seem to possess vast knowledge of other Marvel realities, utilizing the same designations; whether this is simply narrative convenience on behalf of Marvel's authors or an unusual decision by these agencies to utilize an effectively alien catalog method is as yet unstated.
The numeric designations of these alternate universes have been confirmed by Marvel Comics throughout the years and compiled in 2005's Official Handbook of the Marvel Universe: Alternate Universes, and in Marvel publications since the release of the Handbook. The prevalent method of labeling an unnamed universe is to derive numbers in some way from the publication date of the relevant issue featuring its first appearance. This is, in turn, based on the mistaken belief that "Earth-616" derived its number from the publication date of The Fantastic Four #1 (Nov. 1961), although the origin of this term in particular has been under debate. Many official numbers are random or use other numbers as a base, the best example of this is Ultimate Marvel. 1610 is the swapped numbers of 616 with a 0 to differentiate it from the already existing 161. In addition, many universes have also been designated with numbers by fans with various methods for the numbering, such as the birth date of an important Marvel staff member (artist Nelson Ribeiro for the Transformers U.S. Universe, Earth-91274) or the spelling of a name with a touch-tone phone (Animated Silver Surfer Earth, 936652, spells out Zenn La).
Also to be noted is the Marvel Wikia's TRN (Temporary Reality Numbers) system, which is an internal control number for the mentioned fan wiki site to categorize "realities" is entirely unofficial.  It is often mistaken by casual readers as official numbers.
In 2014, during the publication of Spider-Verse, writer Dan Slott posted on Twitter that the numbers that appear in wiki entries and handbooks don't count, only those that are published within "actual" stories do. This was in response to the questions that the different numbers for some Earths appearing in Spider-Verse brought up, such as the Spider-Friends being from Earth-1983 and not the believed designation of Earth-8107. This has created some debate among readers as some believe that the "Spiders" with numbers that don't match the "original" ones are alternate versions or if the former numbers should be completely dismissed, despite being official.
Main alternate universes
Below is a short list of the main universes in the Marvel Multiverse:
|Motion Picture Funnies Weekly #1 (1939)|
|Ultimate Spider-Man #1 (2000)||
|Night of the Sentinels (Part 1) (October 31, 1992)|
Marvel Cinematic Universe (MCU)
|Iron Man (May 2, 2008)||
|Marvel Tails #1 (1983)||
|Spider-Man 2099 #1 (1992)||
|What If? vol. 2 #105 (1998)|
|Ultimate Fantastic Four #21 (2005)|
|Avengers #85-86 (February–March 1971)||
|Star Brand #1 (1986)||
|newuniversal #1 (2006)|
|Strikeforce: Morituri #01 (1986)||
|Dr. Zero #1 (1988)|
|Razorline: The First Cut #1 (Sept. 1993)|
|Hardcase #1 (1993)||
Disney XD's Marvel Universe
|Great Power (Part 1) (April 1, 2012)||
|Edge of Spider-Verse #2 (2014)|
- David, Peter. X-Factor vol. 2 #25
- All New Savage She-Hulk #1
- "Alternate Earths". Marvunapp.com. Retrieved 2015-06-21.
-  Archived October 16, 2007 at the Wayback Machine
- "Dan Slott on Twitter: "Nick confirms Japanese Spiderman (that's the only time I write it without the hpyhen) from the '70s live acti... https://t.co/xYJBGhJfKz"". Twitter.com. Retrieved 2015-06-21. External link in
- "CCI, Day 4: Ellis talks "newuniversal"". Comic Book Resources. 2006-07-23. Retrieved 2012-08-02.
- Marvel Encyclopedia Volume 6: Fantastic Four (November 2004)
- Official Handbook of the Marvel Universe: Alternate Universes 2005
- Marvel Legacy: The 1960s Handbook (2006)
- Marvel Legacy: The 1970s Handbook (2006)
- Marvel Legacy: The 1980s Handbook (2006)
- Marvel Legacy: The 1990s Handbook (2007)
- Appendix to The Marvel Universe Alternate Universes Page
- The word "universe" in this context