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"Before there was thought, there was this place. One Earth. With a single history. But with the coming of man, came the illusion of free will. And with that illusion, came chaos. With every choice we make, we literally create a world. History branches in two, creating one Earth where we made the choice, and a second where we didn't. That's the secret of the universe, you know. Billions of people, making billions of choices, creating infinite Earths. Some so similar to each other that you could spend a lifetime searching for any difference. Others so radically different, they defy comprehension."
Sometimes a writer creates a universe almost exactly the same as ours, but with slight differences. Some settings refer to not just one other dimension
, but to a whole set
of other dimensions and universes. A system of distinct worlds exists, often interconnected in a way that allows characters to travel to and from them. It might be as a tourist who just goes to look and tries not to change anything, or as a participant who goes in and interacts with the people in the other universe.
can move between universes and explore the multiverse. While it is possible they don't have a choice in their destination, sometimes they do. There are a wide variety of Interdimensional Travel Devices
available but the most common are gates
In some occasions it's the way for a creator to tie several different works via Canon Welding
, or to justify a Crossover
This provides all sorts of interesting ideas for things you can do, for good or bad. If it involves trans-universe Sex Tourism
, you have "Your Universe or Mine?
" (or Screw Yourself
sometimes). However, beware Evil Twin
, and similar beings.
Sometimes, the Multiverse is protected by a Guardian of the Multiverse
. The Multiversal Conqueror
, on the other hand, wants to conquer
or destroy it.
the same thing as Alternate Continuity
, but it makes a handy way to link them if the writers are so inclined. See also Bizarro Universe
, Another Dimension
and Alternate Universe
. Compare Rubber-Band History
. If one universe acts as a Cosmic Keystone
that the others are based on, that's the The Earth Prime Theory
For works set in the same universe, see The Verse
open/close all folders
- Bokurano: The main characters are fighting aliens who are attempting to destroy the Earth. Eventually it is revealed that the aliens are actually humans from alternate Earths. The Earths tend to be fairly similar and can easily be mistaken for one another (which the main characters did), though alternates of individuals from one world to another are very rare.
- While on the surface Digimon appears to be a case of regular continuity reboots, the WonderSwan video games establish it instead as a multiverse. Almost every anime series, manga and video game of the franchise has its own entirely separate versions of the real and Digital World (except Digimon Adventure 02 and Digimon Xros Wars: The Young Hunters Leaping Through Time, which are sequels and so exist in the same world); the WonderSwan games follow Ryo Akiyama's travels between a few of them. Digimon V-Tamer 01 had three special chapters in which Taichi Yagami and Zeromaru interact with other Digimon universes, namely those of Digimon Adventure (which has its own version of Taichi Yagami), Digimon Frontier and the WonderSwan games. As such, almost all incarnations of Digimon take place in a different human world/Digital World pair in the multiverse, and if you know what you're doing (or have a dimension-jumping nemesis, in the case of Ryo Akiyama) you can travel between them. In addition, some canons have other dimensions tied to that particular universe; Digimon Adventure had the Dark Ocean and a surreal world wherein one's wishes defined reality, with others accessible through card combinations at a gate in Vamdemon's castle, and Digimon Xros Wars: The Young Hunters Leaping Through Time features DigiQuartz, a bizarre Dark World in between the Real and Digital Worlds.
- Katekyo Hitman Reborn! has Byakuran become a Physical God of all parallel universes, using the three sets of rings and pacifiers in order to do so.
- The setting of Lyrical Nanoha is advanced enough to have fairly casual inter-dimensional travel, with the Time-Space Administration Bureau monitoring the security, safety, and cultural growth of every dimension.
- From some point of the series onward, Hatou in Murasakiiro No Qualia can interact with all the parallel worlds. Each of these is one of the infinite possibilities for the flow of events that didn't get determined in her world.
- Though not confirmed officially, the Evaverse is implied to use this trope between the various continuities and spinoffs. Kaworu appears to be aware of and/or remember every single one, including the anime, the mangas, the games, even the Rebuild films. If true, it means he's the fucking creepiest Stalker with a Crush and Memetic Molester EVER since he's stalking his (male) love across several universes.
- Noein has this where every universe is a For Want of a Nail situation, running off the theory that for every decision made, Another Dimension is created where the other option was chosen. Much philosophy ensues.
- Slayers takes place in one (sometimes called “the red world”) of four universes, each of which has a good and evil god with five subordinates a piece, all projections floating atop a multiversal golden sea of chaos, A.K.A. The Lord of Nightmares. This doesn't really come into play for the most part, aside from in the anime-original TRY season, which concerns “overworlders” searching for five Plot Coupon weapons from their universe…
- Tenchi Muyo! is the one huge metaseries with literally tens of alternative continuities, explored in various TV series, OVAs, novels, mangas, doujinshis etc. It also includes other series and titles by the same author and studio, and even the works by the other creators with sometimes completely different premises. It was explicitly stated by its creator, Masaki Kajishima, that all these titles and interpretations are true and represent different aspects of the same Multiverse, and he doesn't mind sharing. On the other hand, he restricts himself to the Tenchi Muyo! Ryo-Oh-Ki (that is, original OVAs) storyline and its spinoffs like Tenchi Muyo GXP, and consider it the main and central storyline.
- TengenToppaGurrenLagann: Three Words: Multi-Dimensional Labyrinth. The Anti-Spiral effectively flings the consciousnesses of every member of Team Dai-Gurren to separate alternate realities without their true memories. According to the Anti-Spiral, these realities are "created instant-to-instant as they are perceived." It is also stated that the Anti-Spiral home world is hidden in-between the 10th and 11th dimensions. Finally, most of the final episode takes place in a "super-spiral universe where thought is given form."
- When They Cry uses and abuses this concept for its Groundhog Day Loops. The multiverse can be viewed only in the sea of kakera/pieces/fragments. In that sea, each fragment is essentially one possible path that the world can take. Umineko no Naku Koro ni introduces the idea of voyager witches, such as Bernkastel and Lambdadelta, who are the only beings capable of traveling the different fragments, and creator witches, who are the only ones capable of creating new fragments.
- Yuuko from Xxx HO Li C is called the Witch of Dimension for her ability to create gates to any Alternate Universe. It's her services which allow the cast of Tsubasa Reservoir Chronicle to hop for one dimensions to another trying to collect all the feathers.
- The comic Fables mainly features our own world, but also a indefinite number of Fairy Tale worlds which are connected by gates. The gates to our world are closely guarded by the New York Fables since they were conquered by the Adversary.
- This latter plays a role in the War against the Adversary.
- So did the comic book Grimjack.
- Very early on, the Archie Sonic the Hedgehog comic parodied the DC multverse with a literal "superhighway" connecting the various worlds. In a "Bizarro" universe, Dr. Eggman is a kindly veterinarian, while Sonic and his cohorts are evil hooligans in biker outfits. In another, Dr. Eggman was nearly defeated by the Freedom Fighters, but turned himself into a robot as a last resort (and he's even more kill-crazy than the original).
- Every Sonic game and television show is in canon, except that most exist in multiple universes, or 'Zones'. This includes: The 'Prime' Universe, the Sonic Rush Dimension, the Sonic Underground Universe, the (inevitable) Sabrina the Teenage Witch crossover, and a Sailor Moon-inspired universe where Knuckles wears a tuxedo. Go figure. The "real" world is yet another universe, and features lawyer-friendly versions of Fox Mulder and Dana Scully, hot on the trail of a giant blue talking hedgehog. (Sonic Live)
- The comic books Those Annoying Post Brothers and Savage Henry focus on Bugtown, a infinite-sized City of Adventure which connects to an infinite number of alternate worlds.
- Zenith, a 2000 AD series, features this. Perhaps not surprisingly, its author Grant Morrison is one of the creators responsible for bringing back the DC multiverse.
- Major staple of The DCU and Marvel Universe comics (although DC attempted to get rid of it in the '80s; it's back now after the events of Infinite Crisis and 52).
- However, the DCU multiverse was pared down to just 52 universes, some of which are recognizable from various Elseworlds stories, some of which are wholly new creations or amalgamations of worlds from before the original Crisis on Infinite Earths. Earth 2 of the New 52 deals with events that happen on one of these Earths, and Grant Morrison's The Multiversity series has six of its issues each dedicated to one Earth within The Multiverse, plus a multiverse guidebook.
- Morrison drew up a map of the DCU multiverse◊ as it stood circa The Multiversity (the present page image). Basically, the entire multiverse exists on a vibrational spectrum from red (matter) to blue (thought). At the centre, covering red and orange, is the Orrery of Worlds, with the 52 universes and the Rock of Eternity contained within the Bleed. Marking the boundary of the Orrery is the Speed Force Wall. Further out, from yellow to green, is the Sphere of the Gods, containing all of the DCU's various gods and archetypes - this is where Apokolips, New Genesis, the Dreaming, the Silver City, etc., are. At the border of the Sphere is Limbo, where the lost and forgotten of the Orrery end up. Blue is the Monitor Sphere, where the Monitors used to oversee the Orrery before their unmaking in Final Crisis. Marking the final boundary of the multiverse, and the limit to thought, at furthest blue-shift is the Source Wall, beyond which is the Overvoid, where lie the Monitor-mind that spawned the Monitors, the Source, and the Unknowable.
- The Wildstorm multiverse consists of a 196833-dimensional snowflake-shaped arrangement of universes, flat sheets of information that their inhabitants interpret as three-dimensional (or what have you). Between them is the Bleed, red swirly stuff of vaguely-defined properties. The Bleed, if not the snowflake, has recently been incorporated into The DCU.
- After the New 52 reboot/relaunch in 2011, there is no "Wildstorm multiverse" anymore, and all the Wildstorm characters and stories are incorporated into the rebooted DC Universe.
- Concurrent with The Multiversity was an arc in the main DC comics revealing that fragments of previous DC timelines and alternate universes had been preserved by Brainiac (such as the various pre-New 52 DC timelines, the Flashpoint timeline, the original Wildstorm universe, the original Charlton Earth-4, etc.), building up to Convergence, where the residents of the fragments finally met.
- The DCU and Marvel Universe are also part of one omniverse as evidenced by crossovers that have been referenced later by both companies (making them canon). Both also contain multiple alternate futures and the characters from the past and future of other universes. Now, go back and read that again.
- Warren Ellis' run on X-Man utilized another conception of the multiverse, where in addition to Parallel Universes, there's a "spiral of realities" stretching above and below, with the universes "downspiral" being significantly more chaotic and difficult for life to develop/survive in than the the relatively advanced and idyllic universes located "upspiral".
- There are in fact two types of alternate universe in the Marvel Universe. The first are different dimensions adjacent to the regular 616 verse, such as the Microverse and the various magical verses; the second are parallel universes, which are usually alternate timelines, and presumably each has its own adjacent verses too. It's not always clear which is which- the Negative Zone, for instance, is vague on if it is the first or second kind, so the one encountered by the regular Fantastic Four and their Ultimate counterparts could actually be one and the same (and the Nihil encountered by the latter wasn't a counterpart of the regular FF foe Annihilus, but a member of the same species- which is why he referred to himself as a member of a "caste" and already knew who Reed Richards was in their first meeting).
- Issues #17-20 of My Little Pony: Friendship Is Magic (IDW) features a magic mirror that takes explorers to various Alternate Universes. The focus of the arc is on one Bizarro Universe, with evil versions of the good characters and vice-versa. The crisis occurs because good!Celestia falls in love with the alternate world's King Sombra, but their travels have weakened the bonds separating the realities, allowing evil!Celestia to try and take over both.
- The Chance Encounter crossover series Uses this as a plot device, with the main characters hopping around a collection of universes (LOTR verse, Kingdom of Heaven verse, POTC universe and the Troy universe), mostly by means of shipwreck.
- The travel method has become something of a Running Gag, with one of the main characters (Balian) being regularly advised to stay on land. Even that doesn't work. Mostly they tend to arrive in tree's, leading to Legolas remarking that whoever organises these jumps has a serious lack of imagination.
- Code: Pony Evolution uses this to eplain how the world's meet.
- AA Pessimal has created several ongoing tales concerning the Discworld contacting various aspects of "Roundworld" (see below). Ponder Stibbons, who is perhaps more of a research and theoretical physicist than a Wizard, finds himself among congenial like minds when he visits the Roundworld of The Big Bang Theory in The Many Worlds Interpretation. His Assassin girlfriend also finds friends she can bond with in Penny, Bernadette and Amy. In future chapters, Sheldon Cooper and the gang get to visit the Discworld. Mayhem and misunderstanding ensue.
- In another fic, Doppelgangers, the loose ends concerning Rincewind's temporary visit to Earth as Professor van Rijnswand are dealt with. It is discovered that all Discoworld people have identical body doubles on Earth. This explains a lot.
- The Emiya Clan runs on this. With a few exceptions (the Shonen Jump big three, Warhammer 40k, Fairy Tail, DBZ, and a couple others forbidden by the community) every fictional universe is stated or implied to exist somewhere and in some capacity. As such, the possibility for shout outs and crossovers is huge. Whether through time travel, dimension hopping, space, or magician relatives, any idea can make an appearance so long as the authors approve it.
- Major staple in Hottie 3: The Best Fan Fic in the World on the count of it being a Mega Crossover. There is also the concept of the omniverse, a multiverse of multiverses. There are a total of thirteen multiverses in the omniverse.
- The Infinite Loops start because the computer the multiverse runs on had a system crash.
- JLA Watchtower and DC Nation laughed off "52 Pick Up" (as referenced above), going with the older concept of Hypertime.
- My Little Unicorn: Unicornicopia is supposedly part of only one of many dimensions in a multiverse, whose worlds the unicorns can visit. But the author repeatedly mixes up the terms planet and dimension to the point where he refers to the planets themselves as other planes of reality.
- The remake attempted to fix this by saying that they are in fact planets, but transportation between planets is still called "dimension travel".
- Used in Code Geass: Occulta Rising.
- The Open Door is centered around the concept of the so-called heroes exploring the Mega Crossover multiverse in search of ways to improve themselves in preparation to Punch Out their enemies. Universes are sorted according to an "energy gradient", which roughly serves as a Sorting Algorithm of Evil by paralleling each universe's capacity for technology, magic and psychic power. Parts of it have been sealed off and can only be accessed from other parts of the multiverse through "hub universes", with that of Suzumiya Haruhi serving as one of these. Interestingly, it also has Alternate Universes; the second chapter shows that at least one version of Neon Genesis Evangelion different from the native Thousand Shinji one exists, while later chapters also show that canon!40k also exists.
- The Pony POV Series establishes one of these when Applejack looks into the Truth and sees a multitude of Alternate Universes, many of which are Shout Outs to other fics or anime/cartoons/television/etc. It's also with noting that the series uses The Multiverse — it's stated several times that all of these universes exist, and are all as real as the main series universe. Also, it's mentioned that all these universes are connected to a "Heart World" (strongly implied to be the canon universe); changes in the Heart World affect the other worlds connected to it, but if these worlds are somehow disconnected from the Heart World (as AJ does for the POV-verse in "AJ's Dream"), they are free to continue on their own without being contradicted.
- Of all the universe shown, a couple get special attention and focus. First, there's the "Orangejack" universe, which shows what would have happened has Applejack chosen to stay in Manehattan — Big Macintosh becomes the Element of Honesty in his sister's place, while she becomes a successful businessmare, meets the love of her life and has children. Applejack ends up meeting Orangejack, and together they defeat their potential Nightmare-self, Nightmare Mirror. The other universe, which gets even more attention, is the Epilogue timeline, which shows what would have happened had Discord won — he turns the discorded Mane Six into his enforcers, and turns the world into Pony Hell.
- There are also a few bits of Recursive Fanfiction that are written as Alternate Universes to the main POV-verse, but so far only one has been declared official by the main author.
- Stars Above uses this concept.
- Mirror Multiverse uses this as a plot device, with the main characters hopping around a collection of universes.
- The Subspace Emissary's Worlds Conquest is a multiverse of all the video game settings the author can think of.
- The Multiverse plays an important part in Super Milestone Wars and its sequel.
- The Multiverse also plays an important part in The Sweetie Chronicles: Fragments: each of Twilight's fragments was placed in a different universe, which Sweetie Belle must then travel to and collect.
- With Strings Attached takes place in or mentions at least six different universes, and Jeft refers to existence as the Infiniverse.
- The Multi-Dimensional labyrinth concept described by the Anti-Spiral in Tengen Toppa Gurren Lagann has the potential to incorporate all of Gurren Lagann's Parallel Works, as well as any and all forms of fan-fiction, as canon because the Alternate Universes that make up the Multi-Dimensional Labyrinth are created the instant they are perceived.
- The sci-fi thriller Coherence explores the idea of Alternate Timelines crossing paths during a Temporal Paradox caused by a comet passing earth.
- The Big Bad in the movie Last Action Hero discovers since he can cross over to other movies and other worlds, he can bring back the worst of the worst villains. They'll have a formal party: Freddy Krueger and Jason can supply the meat, Hannibal Lecter can do the catering, etc. And it will all take place in what is apparently the "Real World", because here the bad guys can win!.
- The basic premise of The One is that Gabriel Yu Law defected from a group known as the Multiverse Authority after killing one of his counterparts. By killing his counterparts he is able to absorb their power and become more powerful. His new goal in life to destroy every single one of his counterparts and become a God, not knowing that since the collective energy of his counterparts is divided among all of the survivors, his last counterpart is equally as powerful.
- Anathem by Neil Stephenson combines this with of all things Platonic Epistemology to very severely deconstruct many aspects of the multiverse. For example, atomic nuclei are subtly different between universes so any reaction between molecules from different universes is retarded (i.e. breathing).
- Astral Dawn by Adam R. Brown tackles this in a somewhat different way, as the multiverse is referred to as the Nursery of Dimensions. A race of extradimensional aliens called the Aash Ra are charged with safeguarding the Nursery. A single universe out of the multitude lies at the heart of the Astral Dawn saga. Because of its nature, it is called the anomalous dimension.
- Variation: Timothy Zahn's Cascade Point stories feature a faster than light drive system which has the side effect of showing you alternate versions of yourself whenever you activate it, based on different possible outcomes of your life. At least one story features a Phlebotinum Breakdown that drops the ship into one of those universes. It is a Multiverse, but it's not one where you can easily travel between worlds.
- Kate in Choices by Deborah Lynn Jacobs. After her brother dies, she starts traveling between new universes with only slight changes from her own. For example, in one she was a pushover. In another she was a Perky Goth. She would usually go to sleep and wake up in a new universe.
- Roger Zelazny's The Chronicles of Amber has one reality, Amber, which casts an infinite number of Shadows, each one a full world (with Earth among them). The Princes of Amber can travel at will to these worlds by using Tarot cards as portals, or by walking the shadows and altering them until they stand in the world they desire.
- The Coming of the Quantum Cats, while generally forgettable, has some fun with this trope. The great scientist Dominic Desota invents a machine for travelling between universes, but in one universe it's stolen by General Desota, who aims to become a Multiversal Conqueror. Opposing him are the heroes, Senator Desota and Nicky Desota.
- Colin Kapp's The Dark Mind (also published as The Transfinite Man) uses this. The alternate universes were originally empty until mankind (in the form of the evil Failway Company) discovered them and, basically, turned them into vice dens.
- Stephen King's The Dark Tower series and the numerous books that feed into it (or got sucked into it) is based on the notion that all of the weird alternate realities visited by the Gunslinger, plus all of the alternate continuities of King's earlier books are part of a Multiverse that are all connected by the titular tower. All these worlds are apparently subservient to the world in which the fictionalized version of King lives, and the characters discover that they are all in fact being channeled by King the novelist, a la Stranger Than Fiction.
- The Discworld novels often allude to a multiverse. Since all libraries, everywhere, in every space, universe and time are connected, you can reach this L-space in the Library of Unseen University. If the Librarian lets you in, of course.
- Also, in The Colour of Magic, Rincewind and Twoflower briefly find themselves occupying/incarnated in/deluded into thinking they are alternate universe versions of themselves, sitting next to each other on an airplane in a world that appears to be our normal Earth.
- Our Earth plays a greater role in the Science of Discworld series, where the wizards know it as "Roundworld".
- Moreover, the existence of alternate worlds (i.e. different legs of the Trousers of Time) is a given in several Discworld novels. Granny Weatherwax starts picking up random memories from these alternate worlds in Lords and Ladies, and Sam Vimes accidentally swaps P.D.A.s with his ill-fated counterpart from an alternate world in Jingo.
- Also in Lords and Ladies Ponder Stibbons (a wizard version of a physicist) tries to explain the "many worlds'' principle to the Archchancellor (chief Wizard). Of course this goes badly as the Archchancellor is mainly concerned about why his trousers have anything to do with it, and why his parallel self never sent him a wedding invite...
- Isaac Asimov's The Gods Themselves is about the discovery of a way to transport materials from our universe to another onenote where the Laws of Physics operate slightly differently than they do here. The practical upshot of this is that the difference in physical law can be harnessed to create free, unlimited power. It's eventually discovered that continued use of this power source will result in the Solar System collapsing into a quasar. Worse yet, the aliens from the other dimension who created this transdimensional transportation technology are fully aware of this, and are taking advantage of our desire for free energy to prolong the life of their own star.
- His Dark Materials features many an Alternate Universe, with a few powerful items allowing one to travel between them. There may be no limit to the number of separate worlds and universes.
- Introduced as the Whole Sort of General Mish-Mash in Mostly Harmless. As explained, any random slice of the Mish-Mash, at any angle, is seen by the inhabitants a functional 4-dimensional universe. This means that parallel universes a) aren't parallel, and b) aren't universes.
- The Narnia books mainly feature travel to and from the titular Narnia, but in The Magician's Nephew it's explained that our world and Narnia are only two of a Multiverse of worlds. We only ever see three, though. Four, if you count Heaven, although this it is portrayed as being as clearly and obviously different from the rest as a cube is from a square.
- The entire point of the Paratime series by H. Beam Piper was that the main character's culture had exhausted its resources and was sponging off the entire Multiverse.
- Perry Rhodan is explicitly set in a multiverse, but deliberate travel between different universes isn't easy or necessarily safe. Problems involve the (at Galactic tech levels) largely unsolved issue of trans-universal navigation and the problem of adapting to the new physical laws of the destination, which has resulted in "strangeness shock" rendering entire starship crews comatose for months on arrival in the past. The focus of the action thus remains on the default 'main' universe, though interaction with others (including one in which time runs much more slowly, one that consists entirely of antimatter, and one that was and presumably still is heading for an artificially accelerated 'big crunch') has occurred in the past.
- The Quantum Enchantment trilogy and its sequel by Kim Falconer uses the 'many-worlds' concept as a plot device. Working from memory, there is a dystopian Earth a few hundred years in the future, and a completely separate world where magic and the like are common place. Throughout the series, the characters manage to get themselves lost in the 'corridors' between the worlds, often returning to what would be their home but for some sort of twist- a battle was won instead of lost, time flows in a different direction, person X never existed. It gets somewhat confusing after a while.
- The Riftwar Cycle, by Raymond E. Feist involved several universes with magical travel between them. It's always dangerous though, because opening a hole in your universe may attract the attention of beings who were (barely) defeated once by gods...
- Sergey Lukyanenko's Rough Draft-Final Draft duology is set in a multiverse where travel between universes is accomplished using the seemingly magical Towers which in reality were created through highly advanced technology developed by the natives of a universe that suffered a devastating nuclear war.
- Vasili Golovachov's The Saviors of the Fan duology (made up of The Envoy and The Deliverer) has a myriad parallel worlds some of which are similar to ours, while others vary wildly. And that's just those organized into a linked structure called the Worldfan, of which our world is a part, with the implication that there are countless other worlds. According to the protagonist's half-Japanese friend, some of these worlds may be familiar from folk tales or science fiction/fantasy novels, as information has a tendency to "leak" between the worlds, meaning all those stories are actually true in other worlds. There is a world where the mere act of moving alters the surrounding reality, or a world made up of a gigantic tree.
- Transition by Iain Banks
- In The Wheel of Time, there is a multitude of possible other 'verses, called the 'Worlds That Might Be', which are basically Alternate Universes. The less likely they are, the more faded they look. A channeler can be transported to one of these by using a Portal Stone and the One Power.
- Diana Wynne Jones's series, stand-alones and short stories often feature Multiverses or at least two different alternate realities. Count them:
- The trope's name comes from Moorcock's books. His many books range a vast array of worlds yet a sizable proportion of them are connected via Canon Welding. Robert A. Heinlein used this name in The Number of the Beast (see below) as well.
- Robert A. Heinlein has written about Multiverses more than once. The novel Glory Road has magical inter-universe travel, and several of his later novels (starting with The Number of the Beast) involve the Burroughs drive, an invention that lets you travel to other universes; but because of how the Multiverse works, those nearby universes will be the favorite fictions of the users of the drive. So you can leave Earth and the next universe over will turn out to be Oz... As a side effect, Heinlein managed to tie together practically everything he ever wrote into a single setting.
Live Action TV
- Frequently a Discussed Trope on The Big Bang Theory
Penny: What's a Multiverse?
Sheldon : GET HER OUT OF HERE!
- Charlie Jade: the Alphaverse (a Crapsack World and a Dystopia) is running out of clean water from its excessive pollution. So they use a portal to steal water from the utopian Gammaverse. Charlie Jade ends up in the world in between — the Betaverse, a.k.a. our world — when things go wrong with the portal. Later on he finds out that the halucinations he's had through his life are actually the result of his ability to travel between the verses, and he returns home before deciding he liked the Betaverse better than Alphaverse. Long story short, the whole series is based around this trope, including the cliffhanger season finale (from which the show didn't get renewed) that would have revealed a fourth universe.
- 'Community' delved into the multiverse in Episode three, season three "Remedial Chaos Theory" Where Jeff decides to roll a dice in order to decide who has to get up to collect the pizza, in doing so he creates six different timelines with vastly different outcomes. The dice returns in the final episode of season four where they each face off with the victims of the dices worst timeline; the gangs "evil counterparts."
- Doctor Who is a bit tricky. There are alternate timeline-style universes, like the fascist universe of Inferno, or Pete's World from "Rise of the Cybermen"/"The Age of Steel"; post-the Last Great Time War, it's potentially multiverse-destabilising for a TARDIS to hop between such universes. There are also pocket dimensions linked to the main universe, such as E-Space or the Land of Fiction.
- In the middle of the first season, Fringe suggests a multiverse through the ZFT Manifesto. In the season finale Olivia goes there and meets Walter's old partner William Bell—in his office in the Alternative World's still-standing World Trade Center.
- The Alternative Universe is further explored in Seasons 3 and 4, as both universes first suspect each other of trying to destroy the other and then team up to fight a common enemy. Two possible futures of the Prime Universe incorporated similar conditions as the Alternate Universe, in keeping with the idea that the evolution and decay of the Alternate Universe was slightly ahead of the Prime Universe. The show conveniently applied a red/blue color scheme to differentiate the "Red-Verse" and "Blue-Verse."
- In Kamen Rider Decade the titular Kamen Rider Decade must travel through nine Heisei-Era Rider Worlds to save the Multiverse...only to discover there are a lot more than nine. Decade also crosses over with Samurai Sentai Shinkenger, a world without Kamen Riders. (Then other Kamen Rider/Super Sentai teamups would meet without saying that dimension-hopping happened. It's best to not think about it.)
- In Lexx there are only the Light Universe and the Dark Zone. And the Dream Zone. And the Other Zone.
- The TV show Sliders did this, although the heroes had no control over where they ended up each week.
- Stargate SG-1 had a handful of episodes where characters traveled to alternate timelines. The first season finale's storyline was kicked off when Daniel accidentally activated an alien artifact and went to a timeline where he had never joined the Stargate program. A later episode used the same artifact to help an Earth in an alternate timeline that was faced with looming invasion, and other ways of accessing alternate universes were later found as well.
- The season 9 episode "Ripple Effect" turned this Up to Eleven, with dozens of alternate universe versions of SG-1 coming through the Stargate due to some technobabble involving a black hole (and the meddling of one of the alternate teams.)
- Stargate Atlantis also has several episodes that make use of the multiverse. The first has Mckay's sister write an equation that allows connections to alternate universes to be made. Mckay uses it to try to make an unlimited power source. the Mckay from the universe he connected to has to cross the barrier to tell him it's a bad idea. The same technology was later used by Mckay's rival back on earth to try to combat global warming it didn't work. And yet another Mckay from a different universe uses the same technology to build a Universe Hoping Starship again, it didn't work which sent the team from this universe on a wild ride. One just has to wonder if Mckay really knows what he's doing when it comes to the multiverse
- Kirk, McCoy, and several others were transported to a Mirror Universe in the "Mirror, Mirror" episode of the original Star Trek, in which a dark Earth-based empire ruled the galaxy. This was very much an In Spite of a Nail universe, since everything was much the same except the moral/ethical bent of the Federation's counterpart and its citizens.
- Years later, the cast of Star Trek: Deep Space Nine returned to this universe to discover that the revolution Kirk had encouraged its native Spock to foment had happened; unfortunately, its effects were not necessarily for the better.
- Star Trek: Enterprise revisited this again in "In a Mirror, Darkly", just to hammer it home that Humans Are Bastards.
- In 3rd Rock from the Sun there is a two part episode where the aliens visit an alternate universe (because they are bored) where they settled in New York instead of Ohio.
Dick: You may see people you know too. But FYI they may have made different life choices.
Harry: I see, in this universe Officer Don could be an old Vietnamese woman.
Sally: No Harry, they have the same bodies. Dick is saying they'll all probably be gay.
- Once Upon a Time and Once Upon a Time in Wonderland: Most of OUAT takes place in Storybrooke, a town created by magic that exists in the Land Without Magic, which is similar to the real world. The curse that created Storybrooke also trapped many people from The Enchanted Forest there, characters from various fairy tales and other stories. Other worlds include Neverland, Wonderland (in which Spin-Off series Once Upon a Time in Wonderland takes place), Oz, and the Land Without Color (a Deliberately Monochrome world where Dr. Frankenstein is from). Word of God is also that the world Alice is from in OUATIW isn't actually Victorian England but another world similar to it.
- Wizards of the Coast long ago published a set of generic supplements for handling deities in roleplaying games, called The Primal Order. One of the books in this series, Chessboards, covered in exquisite detail how to design and manage an entire multiverse complete with cosmology.
- The GURPS supplement Infinite Worlds provides a setting and mechanisms for not only setting up a Multiverse incorporating all other GURPS books as a background against which to play, but also providing an interdimensional cold war as a driving force behind a potential campaign.
- The trading card game Magic: The Gathering is set in a multiverse, with each expansion set representing a new universe (well, mostly). The game also implies that the players represent Planeswalkers, mages able to travel from one universe to the next essentially at will. The cards played represent magic and land discovered while exploring a given universe.
- The casual variant Planechase literally represents the planeswalking with plane cards that affect gameplay and get cycled in and out as players shift to new worlds.
- Planescape, and by extension, the computer game Planescape: Torment.
- And, through further extension, the whole of Dungeons & Dragons, though there are no or few crossovers between different game settings, such as Eberron showing up in the Forgotten Realms.
- Spelljammer originally combined Greyhawk, Dragonlance, and Forgotten Realms, though like Planescape it can be extended to other settings that don't explicitly say their world isn't in a crystal sphere. The other planes of existence are only accessible from within the crystal spheres however. The Phlogiston that makes up the bulk of the Prime Material Plane is cut off from the planes.
- Planescape in fact explicitly includes the Spelljammer setting as part of its multiverse, along with all the aforementioned settings, as well as Birthright, Ravenloft and implicitly every D&D setting ever devised, including contradictory ones.
- Ravenloft is yet another setting that could bridge the divide between different D&D settings, including otherwise-inaccessible ones like Mystara, Athas, or Gothic Earth.
- Rifts is part of Palladium Books' "Megaverse", which includes all of its other games (naturally), plus a number of other realms with some of the games.
- Torg deals with the invasion of Earth by several different realities (cleverly typified as various classic roleplaying genres), each of which is trying to change our local reality axioms to be like their own.
- During the Karda Nui arc, a Teleporter Accident sends Takanuva to an Alternate Universe instead of Karda Nui. He spends the majority of his screentime traversing various Alternate Universes, until finally making it to his intended destination. Other characters, such as Vezon and Mazeka, also explore Alternate Universes in a similar manner.
- A subplot featuring an alternate, benevolent version of the Big Bad crossing over into the main universe was set up during the same arc, but due to BIONICLE's abrupt cancellation, it ended up an Aborted Arc.
- Transformers has a whole pile of alternate universes which sometimes cross over, and which Hasbro and Takara disagree over which are actually separate and which simply occur to the side of other stories. The Transformers of the Axiom Nexus have grouped all continuities into a number of universal streams, with each stream corresponding to a continuity group. Thus, for example, Primax is the G1/Beast Era family, Tyran is the live-action movies, Gargent is the GoBots, Quadwal is the real world, etc. Some of these are negative-polarity universes in which Decepticons are good and Autobots are evil; these are assigned negative numbers. To make things really nuts, there are also characters known as multiversal singularities, of which only one exists in all reality. Some of these, such as Alpha Trion, exist in every universe simultaneously, while others, like Vector Prime and The Fallen, travel between universes. There are also sparks that resonate across the universe, giving rise to multiple similar but separate versions of Optimus Prime, Megatron, Starscream, and various others.
- Anachronox takes place in one universe but deals with the universe before this one and the universe after this one; if there was a second game, we would have gone to the former. Plot: In the next universe, two forces - "Chaos" and "Order" - are pitted against one another for survival. Order managed to trapped Chaos in this universe. Chaos is trying to find a natural doorway into the previous universe where it seeks to destroy this universe and the next universe, and Order in the process.
- In BioShock Infinite, Elizabeth is able to open "tears" in the fabric of reality, which are open windows to parallel realities. One example is a 1980s street in front of a cinema where Revenge of the Jedi is played.
- This goes Up to Eleven by the ending, where it's shown there is an infinite amount of different dimensions, each of them being linked by the fact of having a man (Booker, Jack), a lighthouse and a city (Rapture, Columbia).
- One of the Elizabeths in the ending is the beta model used in the early gameplay demos. This means that all of the Dummied Out content like Saltonstall and the incidents like saving the mailman from the Vox Populi could be a sort of quasi-canon, taking place in alternate versions of Columbia with alternate Bookers.
- The MMORPG City of Heroes has Portal Corp., a company dedicated to exploring other dimensions. There are several individual missions and arcs where you get to deal with hostile other-dimensional entities, either after they've entered Paragon or at their source. The current state of the City of Adventure can be traced back to a massive invasion from Another Dimension.
- One such alternate dimension, Praetoria, is the focus of the latest expansion, Going Rogue, which fleshes out that dimension beyond Crapsack World Mirror Universe by adding moral complexity and considerably more shades of grey.
- Eternal Darkness: After beating the game under all 3 ancients you find out that the other ancients (the ones that you beat in the previous two playthroughs) were killed by the main character's counterparts in other, parallel universes. Mantorok then overlaps the three realities, killing all three ancients concurrently and leaving the universe free of them forever.
- Though not officially stated, the Rift from Final Fantasy V seems to be a wall separating all the various universes of the Final Fantasy games. Only Gilgamesh has been shown to be able to get around it freely so far. After his banishment there by Exdeath, and his subsequent Heroic Sacrifice against Necrophobe, he sets off on a quest to collect rare weapons, appearing in the worlds of Final Fantasies I (remake), IV, VI (remake), VIII, IX, and XII. At some point, he also manages to find his way into the conflict between the gods Cosmos and Chaos, and is overjoyed to find Bartz there, having been itching to get a rematch against him. Unfortunately, Bartz has only the faintest of memories of his home world in this continuity, making ol' Gilgamesh an Unknown Rival to him.
- Eorzia, the world of Final Fantasy XIV, seems to be a veritable hotspot for wanderers through the multiverse to wind up, so far we have Gilgamesh (naturally), Lighting, Shantotto, and Brick Golems. for the most part they have no actual bearing on the plot and may not be canon, but at least one character ( Krile from Final Fantasy V) has been given a mention in the context of the main story.
- Let us not forget The Crystal Tower, ripped straight out of Final Fantasy III which serves as the endgame content for casual players.
- Kingdom Hearts indulges in this concept with the Worlds; separated by near-impenetrable barriers (unless you can find a way to bypass it), but all sharing the same oceans and skies. Unlike most examples, the Worlds seem to be in one universe instead of scattered across infinite dimensions.
- Makai Kingdom introduced the multiverse concept for the various netherworlds and non-netherworlds introduced by prior Nippon Ichi games (prime amongst them Disgaea).
- The Myst games (and books) are primarily concerned with a magical means of inter-universe travel (and universe creation, if you believe Gehn).
- In Myst III: Exile, Saavedro seems to be capable of annihilating the new D'ni age by destroying the age definition book, so Gehn has a definite point.
- Later games and novels have explained that destroying the book only destroys the link to that particular world, although since said link can never be recreated, it might as well be considered destroyed as far as travelers are concerned.
- Furthermore, though official disposal of Linking Books was historically handled with care due to issues of the special techniques involved in forging the world link, there's very little real harm in the action. Much greater harm comes from writing carelessly which can introduce unstable elements into the world described. The original Myst touches on this with Atrus's musings on the Stoneship Age and this is a major problem for the second game Riven.
- The Nameless Mod mentions that other forum cities exist, and that travel between them is possible. Apparently a Planet Diablo merchant is responsible for the mana potions (that can only be used by a single unique weapon of plot importance) being in the game.
- The Nasuverse is actually made of different different continuities, possibly because the main works are multi-route visual novels. However, actually traversing between Universes is the domain of Magic (i.e. a miracle) so only one character can actually do it.
- Also used as a source of infinite Mana by taking a small amount from an infinite number of alternate realities, using a tool designed by the aforementioned character. Incidentally, this is also a perpetual motion machine since it powers itself.
- The Nicktoons Unite series. The world of every Nicktoon show is actually a dimension in the Nicktoon multiverse.
- In the Perpetual Testing Initiative DLC for Portal 2, this is the Excuse Plot. Since Aperture Science is bankrupt, all test chamber construction has been outsourced to Apertures in other universes, which is then tested in and stolen back. The DLC comes with new Cave Johnson audio that gives us such gems as Space Prison Warden!Cave, Dark!Cave, and Hobo!Cave.
- As well as a universe filled up entirely with money. Two of them, in fact.
- In Ratchet & Clank Future: Tools of Destruction, the all-knowing (for the most part), IRIS Supercomputer mentions that existence is divided into infinite dimensions.
- Shin Megami Tensei III: Nocturne seems to imply that the various Shin Megami Tensei continuities are all connected through the Amala Universe. Raidou Kuzunoha vs. The Soulless Army and Raidou Kuzunoha vs. King Abaddon show the existence of the Akarana Corridor, a tunnel linking several times and realities, further confirmed in Devil Summoner Soul Hackers. The Yamato Perpetual Reactor in Shin Megami Tensei IV links at least three parallel worlds (Firmament Tokyo, Blasted Tokyo, Infernal Tokyo) together through the Reactor Room in Camp Ichigaya.
- The multiverse is a key point to Suikoden Tierkreis, though the player/lead PC only technically ever gets to see one (the reason why is also a plot point).
- Super Paper Mario has this as the plot. Seeing as an Omnicidal Maniac is walking about with a dark book has the future written in it with the way how to end all of existence, Mario ends at a interdimensional crossroads to collect the Pure Hearts.
- This trope is a major plot point in Super Robot Wars Original Generation, with the revelation that the character Gilliam Yeagar is the same character from Hero Senki: Project Olympus, having made his way into multiple Alternate Universes to get back to the world of Elpis in Hero Senki, following its events there. The Big Bad in Original Generation Gaiden is implied to be the same Big Bad of The Great Battle series, as well as the creator of Duminuss, the Big Bad of Super Robot Wars Reversal.
- Touhou involves quite a bit of world-hopping. Based upon a relatively Buddhist notion of the universe, like the Nippon Ichi example above, with multiple hells (Jigoku) and netherworlds (Makai), it gives the heroines plenty of reason to go To Hell and Back. This seems to have been more frequent earlier on in the series, when there weren't as many characters, and Gensokyo wasn't as fleshed out. Gensokyo itself seems to be a semi-self-contained world kept vaguely apart from the real/outside world by the Great Hakurei Barrier, in spite of being physically built in Japan. Alternate worlds the heroines may visit include:
- In the original game, Highly Responsive To Prayers, Reimu has to close an open portal to Jigoku / Hell.
- Phantasmagoria of Dim.Dream features "scientists" who visit Gensokyo from an alternate dimension in order to "study danmaku" using a "probability hyperdrive vessel".
- Lotus Land Story has Reimu and Marisa competing to fight their way into the world of dreams, where Kazami Yuuka resides. Reimu and Marisa also visit another dimension that isn't very well explained in the extra stage, just to beat up the creators for no reason at all.
- Mystic Square features the heroine of the player's choosing invading Makai, the world of demons.
- Perfect Cherry Blossom features the Netherworld, and Hakugyokuro, land of restless spirits, and effective equivalent of Purgatory. It also has the legendary lost land of Mayohiga, home of the Yakumos.
- Yukari Yakumo, a Reality Warper, deserves special mention, as her power of "Borders" allows her to generate portals to any other location or dimension she can conceive of. She can even seemingly create new dimensions, by manipulating the boundary between fantasy and reality, and so make a dream or thought into a real dimension, and then open a portal to it. Needless to say, this makes her a Physical God for all intents and purposes.
- Imperishable Night has... the Moon. Turns out, there's an extremely different world underneath all that barrenness - a highly advanced civilization hiding itself from the "impurities" of the Earth. Revisiting the Moon also becomes the objective in Silent Sinner in Blue.
- Phantasmagoria of Flower View has the Sanzu no Kawa, a mythical, River Styx-like river that separates the land of the living from Higan, the land where the dead wait for their judgment, and, as a result, can wind up in Heaven, Hell, or get reincarnated.
- Subterranean Animism has the Hell of Blazing Fires lying in the cave networks beneath Gensokyo and the Earth in general, presumably in some sort of vague pocket dimension in the Earth's mantle that only appears in Gensokyo version Earth.
- Undefined Fantastic Object has Makai (although some debate as to whether it is the same Makai from before, there's some evidence that it is.) Byakuren was sealed within Makai for trying to unite humans and youkai (and getting hordes of racists on her ass), but is released thanks to the result of her followers' actions.
- All Over The House is linked to The Life of Nob T. Mouse via portals and random dimensional jumps. As a result, there are in-universe examples of crossover media, such as The Blobland Gang stories, which Tesrin of All over the house read as a child. These are based on Hubert Schlongson's visits to Blob City, which is the main setting of The Life of Nob T. Mouse.
- Autumn Bay has the resident Omnidisciplinary Scientist peeking in on other webcomics, treating them as other dimensions in the multiverse.
- Bob and George has a lot of different universes, most of them with completely crazy versions of the characters. (One universe is the universe of the original Japanese Rockman games.)
- French webcomic Dragon Ball Multiverse: An alien race discovers inter-universal travel and gathers the best fighters from every universe to compete in the ultimate tournament. Some of these fighters include a Vegetto that remained fused, a Cell that defeated the Z-Warriors and a Kakarot that didn't lose his memory. The opening few comics imply that the Multiverse is infinite and that the numbers assigned to the various realities are for the sake of the tournament alone. DBZ:M actually goes against tradition by having the "canon" universe receive a moniker other than "One" or "Prime".
- Various characters in Deviant Universe have appeared from alternate universes, and one story arc involved an attack by another universe.
- In Dragon City, Erin finds out that her friend Natasha is the alternate universe version of herself, but with brown scales instead of blue. She was temporarily stuck, but when she got back, she found out that she had been declared dead, so spends most of her time in the main universe.
- El Goonish Shive has a multiverse of worlds sharing many of the same characters. Among them is the main EGS-verse, the Alpha Dimension (where Tedd is a misunderstood Evil Overlord type with a cybernetic hand), the Beta Dimension (where Elliot was born female and Tedd wears square glasses), the Second Life universe (aliens got involved in the American Revolutionary War, Elliot was born as Ellen and went to school with Kaoli), and the less-canon AF04 (April Fools 2004) universe (Tedd was born female, Sara is a goth, and Susan's dad never cheated on his wife).
- And oddly, Tedd is in every universe, something that nobody else can claim. Might be Author Appeal or something more considering Shive's love of Chekhov's Gun.
- Homestuck has a multiversal setting, with the kids' universe and the trolls' universe playing a major role in the plot. It's later revealed that Sburb actually creates new universes that the players can then travel to. Our home universe is the product of the trolls' session.
- Even later, it's revealed that Sburb actually creates multiverses; every possible alternate universe off a base template is encompassed in one Genesis Frog. The sum of all the sessions of Sburb, Genesis Frog multiverses, the Furthest Ring, and the Green Sun is known as Paradox Space.
- In Jix, Lauren was sent to an alternate dimension where Jix's other personality, Remula, rules Earth.
- The KA Mics is a multiverse & even has a company that allows travel between alternate universes.
- The Life of Nob T. Mouse contains a multiverse of sorts through its Quantum History literary device, where each point in time is a parallel universe that may or may not be attached to any other point in time. Although originally devised as an excuse to get around continuity errors, it allows multiple versions of the main characters to exist at once and have different adventures at the same time.
- Parallels: Keeping the spaceways safe one universe at a time.
- Scenes From a Multiverse, a comic about life in an ordinary multiverse.
- Sluggy Freelance has introduced over a dozen alternate universes by this point, ranging from slightly tweaked versions of the main universe to an endless void outside time to Hell itself.
- Ultima Java has an interesting example; there are many alternate universes, but each universe has a corridor connecting different worlds within that universe. So, in effect, universes within universes.
- The Walkyverse has several, but most specifically: the Dargonverse, where Jason's Father's Organization was before it came to the Walkyverse; the NoWalkyverse, where Walky went to college and never joined SEMME; the Dumbiverse, where all of the Walkyverse characters went to the same college and SEMME and aliens don't exist (named for the comic revolving around it, Dumbing of Age), and the Fans! universe, which is...well...yeah. There's also one where Sal and Danny ended up together and had a kid, and a few others that have gone unnamed.
- The season 4 finale of Adventure Time: The Lich opens the portal using the Enchiridion. The multiverse is a series of alternate planes that can be traveled to with portals torn open by objects of power or opened naturally when they eclipse. In the center is the Time Room where The Omnipotent lives whose Time wave emissions allow the flow of timelines for them all.
- Video Land in Captain N: The Game Master is basically a universe for each video game plus the Real World.
- Family Guy, "Road to the Multiverse". Another Brian and Stewie Road Trip episode, this time going through a Sliders-inspired adventure. Some universes were an Alternate History (where Japanese never surrendered in WWII, the Cuban missile crisis, etc.), while others were the characters done in different art styles (the Disney universe, Robot Chicken universe, political cartoon universe, blocky universe, etc.). There was even a short trip to the real world.
- Futurama did this, and we discover a world where coin flips always have the opposite results — as a result, Leela and Fry are married, Bender is gold-plated instead of his usual color ("Bite my glorious golden ass!"), etc. As it turns out, both universes are stored in a box in the other one.
- They later visit dozens of other universes — ones where they're all robots, or hippies, or Romans...
- Also, in an earlier episode of Futurama, there was another universe from across the edge of the universe — where the Planet Express crew saw their counterparts dressed as cowboys. At that time, it was said to be the only other universe.
- Word of God claims in the DVD Commentary that the cowboy one was a parallel universe (thus they're always the same distance from each other but never accessible to each other), the others are perpendicular universes (which means they're accessible to each other but only for a limited amount of time).
- Justice League: Crisis on Two Earths takes a serious look at this trope to the point of near-deconstruction: The main antagonist, Owlman, goes completely Nietzsche Wannabe over the realization that the multiverse consists of the sum of all universes made from all possible outcomes of every single choice ever made by any sentient being (let's just be generous and say 'infinity'). Anything done is by definition meaningless because an infinite amount of universes exist that contain all possible outcomes of everything. Naturally, his conclusion is to perform the one action that would, by definition, have any purpose at all because it cannot have a different outcome: Blow it all up!.
- This was also alluded to in the series Justice League. The main timeline exists on its own, and any changes to the past (as seen in both "The Savage Time" and "Hereafter") will affect the future itself as opposed to branching off - the Bad Future of both respective stories is completely erased after someone Set Right What Once Went Wrong. That said, there are implied to be multiple universes which diverge off the regular one seen - "A Better World" showed a For Want of a Nail wherein Lex Luthor became President of the United States, had the Flash executed and nearly started World War III; this led to Superman killing him and the Justice League to reinvent themselves as a group called the Justice Lords, with a Knight Templar policy towards peace and security. In addition, the above-mentioned "Crisis On Two Earths" was originally written for the DCAU; although reinvented as a more general tale, it's fair to say that some version of that movie's events did happen in between JL and JLU (albeit with John Stewart as the serving Green Lantern, among other aesthetic differences), meaning that its own multiversal concept would apply here as well (if unexplored).
- The end of Spider-Man: TAS featured a team-up of several Spider-Men to prevent Spider-Carnage from destroying a multiverse. One of them didn't have any powers and was really an actor playing Spider-Man in a movie. His universe was strongly implied to be "ours".
- The TV movie Turtles Forever establishes that every single version of the Teenage Mutant Ninja Turtles (i.e. every single comic, TV, and film series) all exist simultaneously as separate universes in a multiverse. The Shredder gets rather pissed when he discovers that there are teams of Turtles in each one.
- The Battle Nexus fighting tournament draws in combatants from all over a multiverse that appears to be a sort of different multiverse concept. Usagi Yojimbo's world is one of them.