Crisis Crossover

This is one way they can start.

"So first there was The Infinity Gauntlet, then Infinity War, and now there's Infinity Crusade. It must be like an annual convention for super heroes that Warlock runs for them. It gives them all a chance to get together and network and catch up on each other's continuity, exchange business and trading cards, pose for holograms with each other, stuff like that. They probably just wish the things were held in San Diego or someplace fun, where everyone could hang out at the beach."

— Marvel Year in Review 1993

A company-wide Massive Multiplayer Crossover which sweeps all the "mainstream" characters in a ficton into a single storyline and, often, takes their own series along for the ride.

The original was Marvel's Secret Wars (1984), but the trend only really caught on with Crisis on Infinite Earths, the event which changed The DCU so much that its history is permanently defined as "pre-Crisis" and "Post-Crisis". It went from April 1985 to March 1986, tying in almost every other series DC published at the time.

After this, it became more and more popular, with not just Marvel and DC but other companies — Malibu, Wildstorm, etc. — getting into the act. Eventually, though, readers were sick of it, and it tapered off, before returning to the scene in 2004 when DC and Marvel both launched new Crisis Crossovers that started Metaplots that are still running today. Time will tell how long it takes for readers to get sick of it this time (if they aren't already).

The advantage of a Crisis Crossover to a publisher is that people reading the main story will want to read the various crossovers, thus increasing sales. The disadvantage is that people who only want to read one of the titles that cross over may be turned off by having to buy all the tie-ins to understand it, thus decreasing sales. In practice, it can go either way, but there's a reason the technique was abandoned for awhile.

In-story, the scope is usually more massive than what may be found in the stories at ongoing comics. Things like the death of a flagship character or events where Nothing Is the Same Anymore for the whole setting usually take place in those stories. But what about the event that kickstarts it all? It may simply take place in the first issue, it may be expanded in a dedicated one-shot (with titles such as "Crisis Alpha", "the road to Crisis", "Prelude to Crisis", etc), or even have been brewing for quite some time already in a previous Comic Book Run elsewhere by the author. For example, Secret Wars (2015), King in Black and War of the Realms are the culmination of The Avengers (Jonathan Hickman), Venom (Donny Cates) and Thor (2014) respectively.

In comics, there are several subtypes:

• The classic is a single mini- or maxi-series, with other titles having a couple issues branded with the crossover's title. Crisis on Infinite Earths itself and Secret Wars II are of this type.
• A second kind is the all-annuals crossover. Many comic series have, in addition to their twelve monthly titles per year, a thirteenth plus-sized annual. An all-annuals crossover takes place entirely in one year's annuals (plus, perhaps, a special bookending issue or two). Armageddon 2001 and Atlantis Attacks! are examples.
• Fifth Week Events. Most comics come out monthly, most comics come out on Wednesday, and most months have four Wednesdays. Four times a year, however, there will be a month with a fifth Wednesday. Instead of moving titles around so that (for example) some comics that usually come out on the fourth Wednesday are pushed to the fifth, the publisher may just schedule an event for that week. Example: Sins of Youth
• Self-contained: A crossover that doesn't crossover. The heroes take a break from their own books to participate in a mini-series, then return to their own books. Examples: Secret Wars and Cosmic Odyssey.
• The opposite is the crossover without a self-titled mini-series; the whole crossover takes place in extant books. Marvel used to do this a lot, as with Inferno and Acts of Vengeance.
• The current format is an expansion of the first type: There will be a core series, one or more spinoff series, probably some one-shots, and crossover into regular titles. Blackest Night, for example, had a core mini-series, seven multi-issue spinoffs, a slew of one-shots (nominally numbered as "new" issues of long-dead series), and heavy crossover into both Green Lantern titles, among others.

When a comic slaps a big, visible "Crisis Crossover" logo on the cover, but only has a token Shout-Out to the Big Event that only peripherally affects the plot of the issue in question, that's a Red Skies Crossover. When a Crossover occurs that involves a couple of characters and their support, but doesn't necessarily affect the large universe, it's a Bat Family Crossover. When the various sets of characters do not interact with each other but still deal with a universal threat, it's a Cross Through. When the same characters from different Alternate Universes work/clash together in a Crisis Crossover, then it's an Intra-Franchise Crossover.

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Examples:

• Comic Books
• Fan Works
• Live-Action TV
• Video Games

Advertising

• The combined forces of KFC, Taco Bell, and Pizza Hut join forces to Defeat the Dark Side in these commercials, done to promote The Phantom Menace.

Anime and Manga

• The Pretty Cure Magical Girl metaseries have their own Crisis Crossover movie series labeled "Pretty Cure All Stars", featuring heroines from all series released until then.
  • However, after quite a few All Star movies and too many heroes to work with, the franchise's Crisis Crossover movie series may be going in a new direction with its upcoming film, "Pretty Cure Dream Stars;" which feature only two Precure teams teaming up and possibly meeting a member of a new team.
  • Then a canonical crossover happened in HuGtto! Pretty Cure when one of the villains froze time and all the Cures had to stop him.
• The 2nd part of the Time Bokan OVA in 1993 involves the Dorombo Gang from Yatterman invading a city populated by other Tatsunoko Production characters, and who should show to stop them but the Science Ninja Team Gatchaman, Casshern, Hurricane Polymar, and Tekkaman?
• Tsubasa -RESERVoir CHRoNiCLE- features characters, Spin-Offspring, Expys, and/or cameos from more or less everything CLAMP has ever written.
• The Majokko Club Yoningumi A-kūkan kara no Alien X OVA is a crossover between Studio Pierrot's most successful Magical Girl series. Creamy Mami, Magical Emi, Pastel Yumi, and Persia all team up to fight alien forces on the moon.
• Digimon Xros Wars: The Young Hunters Who Leapt Through Time has one in its final few episodes, which saw the return of all the leaders and various other members of all previous Digimon teams.
• Yu-Gi-Oh!: Bonds Beyond Time is one between the protagonists of the first three series. It's spawned a fair few fanfiction imitations as well.
• Invoked in-universe in Re:CREATORS, where in order to empower the Creations against Altair, the government formulates a plan to have their creators make a crossover event film in which the characters join forces to defeat Altair due to the fact that the Creations' power-ups rely on the general public to accept and embrace them. The final result is that Altair curb-stomps the whole lot of them because the audience loves her much more and a really twisted version of Only the Leads Get a Happy Ending, with Altair being "the lead" in question.

Film — Live-Action

• DC Extended Universe:
  • The climax of Batman v Superman: Dawn of Justice has Superman, Batman and Wonder Woman teaming up to stop Doomsday.
  • Justice League has Batman, Wonder Woman, The Flash, Aquaman and Cyborg teaming up to prevent an invasion by the New Gods of Apokolips led by Steppenwolf on behalf of Darkseid.
• Disaster Movie can be seen as this, with various movies crossing over as the end of the world occurs.
  • Can also be applied to Scary Movie and its sequels.
  • It seems that mashup parody movies is becoming a genre on itself.
• Godzilla has had several:
  • Ghidorah, the Three-Headed Monster is a somewhat smaller-scale version of this. Mothra had already crossed over into the Godzilla universe in Mothra vs. Godzilla after having her own earlier film, but this one also adds Rodan, who had his own separate film, so that all three monsters could team up against King Ghidorah. This also started the tradition of eventually having all of Toho's various Kaiju showing up in this fused universe.
  • Destroy All Monsters once again had Godzilla, Mothra and Rodan, but also added other Godzilla monsters like Anguirus, Minilla and Kumonga, along with other Toho monsters like Gorosaurus, Manda, Baragon and Varan, all ultimately fighting King Ghidorah.
  • Godzilla: Final Wars features almost every monster introduced in the Showa era facing off against Godzilla.
• Kamen Rider:
  • The first film-length crossover was Birth of the Tenth! Gather All Kamen Riders!!, which featured all nine previous Riders and introduced the tenth, Kamen Rider ZX.
  • Kamen Rider Kiva began the trend of each Rider season having a crossover movie with its immediate predecessor, usually to deal with a villain based on both of their shows or an agent of the Nebulous Evil Organization Foundation X. Some of these movies also feature appearances by a smattering of previous Riders whose actors were available at the time, who show up to help when the main pair need the cavalry.
  • Kamen Rider × Super Sentai: Super Hero Taisen and its followups are larger crossovers featuring not just every Kamen Rider, but every Super Sentai as well. Usually only the current Rider, the current Sentai, and a few previous characters have appearances out of costume. Everyone else only appears in costume, and is either voiceless or played by soundalikes of questionable accuracy.
• Marvel Cinematic Universe:
  • The Avengers (2012) is a crisis crossover for all Marvel Studios movies starting with 2008's Iron Man. However, this was the plan from the very start, as it was first set up in The Stinger of Iron Man and just building with each new film released in the next three years.
  • Avengers: Age of Ultron reunites the team in reaction to events laid out in the intervening films, as well as being influenced by events in Agents of S.H.I.E.L.D. (though the Agents of S.H.I.E.L.D. don't appear).
  • Captain America: Civil War crosses over the cast of the Captain America movies with the cast of the Avengers movies (sans Thor and The Incredible Hulk), as well as unaffiliated heroes Black Panther, Ant-Man, and Spider-Man.
  • Avengers: Infinity War once again ties together various sub-franchises from across the MCU, including ones not included in the previous two Avengers films, in order to both deal with the Greater-Scope Villain of Phases 1-3 (namely Thanos), and to finally tie off the Infinity Stone Myth Arc that has been running through The 'Verse since mid-Phase 1. It has the largest number of superheroes in any MCU film to date.
  • Avengers: Endgame is the direct continuation of the events of Infinity War, climaxing in a Big Badass Battle Sequence between the Avengers and their many allies verses Thanos's army.
  • Spider-Man: No Way Home is such a big Crisis Crossover that it brings together the characters, and therefore universes, of the Spider-Man films already in the Marvel Cinematic Universe (and also Doctor Strange with Stephen's supporting role and a cameo by Wong), with the two cinematic predecessors and pits the three Spider-Man incarnations against a Legion of Doom consisting of most of their villains. It also crosses over further with a mid-credits cameo of Tom Hardy's Eddie Brock and Venom.
• Space Jam: A New Legacy brings together a vast menagerie of Warner Brothers franchises.
• Ultra Series movies tend to do this:
  • Ultraman Saga has Ultraman Zero of the M78 universe working together with Ultraman Dyna and Ultraman Cosmos, despite the latter two being from completely different dimensions: the reason of their unity is because Dyna summoned them through a dimensional portal. They're working together to defeat Hyper-Zetton, an empowered incarnation of the already powerful monster known as Zetton, after all.
  • Ultraman Ginga S The Movie: Showdown! The 10 Ultra Warriors! features Ultraman Ginga and Victory being trained by the aforementioed Zero, to unleash a more powerful fusion form and release various imprisoned Ultras - Ultraman Tiga, Ultraman Dyna, Ultraman Gaia, Ultraman Max, Ultraman Nexus, Ultraman Mebius, and his latest addition, Ultraman Cosmos - so they may work together and defeat a powerful Space-Time Demon, Etelgar, who intends to enslave Ultras and seeks Ginga, Victory and Zero as latest additions to his collection.
  • In Ultraman X The Movie: Here Comes! Our Ultraman!, Ultraman X ends up working with the original Ultraman and Ultraman Tiga to defeat Zaigorg, the Ultramen universe equivalent to Satan, who had been unleashed into the world. The ending also features five other Ultras, including Ginga, Victory and Zero, battling Zaigorg's monster army across the globe while X takes on Zaigorg with Ultraman and Tiga assisting him.
  • Ultraman Taiga The Movie: New Generation Climax has eleven Ultra heroes, from Ginga to Taiga, working in tandem in order to destroy the Malicious Demonic Monster Grimdo.

Literature

• Eugene Sue's 3rd major novel Mysteries Of A People in its final chapter brings the Hero of his First Rodolph into the story as well as the villain of his second (An Evil Jesuit) to do battle with each other.
• A Jane Austen version happens in Death Comes to Pemberley. Wickham's situation ends up briefly binding Pride and Prejudice with Persuasion and Emma.
• Star Trek: Destiny: An epic (and we do mean epic) trilogy of novels of the Star Trek Expanded Universe, bringing together characters from The Next Generation, Titan, Enterprise, Deep Space Nine and Voyager to tell the story of the apocalyptic final war between the Federation and the Borg.
• The Thursday Next series can be seen as a variant of this in later volumes, with literary characters such as Miss Havisham and the Cheshire Cat playing roles in the salvation of all written literature. It runs closer to a Kingdom Hearts-style crossover than a comic-style crossover, though.
• The first phase of the Family Chronicles have this. Heroes And Villains, Death In The DEEPS and Darkness Falls are separate rosters of characters, but the other two books in the phase, Blood And Fire and The Blackest Night combine the three separate casts into one fight for the world.
• The Grand Finale of Warrior Cats, The Last Hope is as close as you can get to a self-contained Crisis Crossover, with loads of screentime for all past and present protagonists, the final battles with all the past villains, and cameos by nearly every ThunderClan cat from the first arc.
• Kim Newman's superhero deconstruction "Coastal City", about what it would actually be like to live in a typical comicbook universe, mentions that "once a year, there would be a crossover free-for-all, frequently involving something enormously powerful from another galaxy, and all the hypers would destroy the city while saving the universe."
• The Stormlight Archive is basically this to the rest of The Cosmere setting, with planar champions and heroes from previous stories coming together to find Hoid and deal with a threat to the entire Cosmere. Numerous characters and objects from prior books are Back for the Finale.
• Michael Moorcock has the "Agak and Gagak" incident, in which no less than four incarnations of the Eternal Champion (Elric, Erekose, Corum and Hawkmoon) are summoned to fight two Eldritch Abominations who threaten the entire Multiverse. It is depicted in two separate novels, from Elric's perspective in The Sailor on the Seas of Fate and Hawkmoon's in The Quest for Tanelorn.
• SD Gundam The Last World features characters from throughout the SD Gundam universe trying to survive an Involuntary Battle to the Death in the titular "Last World". To wit, alongside Sen-Pu Ninja Exia and Gundam the Gold, there's also characters from the Knight Gundam series, BB Senshi Sangokuden, SD Command Chronicles, SD Gundam Force, Gundlander, and SD Gundam Space Time Transfer Gun Voyage just to name a few.

Magazines

• This trope is spoofed in MAD's article about The 8 Greatest Comic Books of All Time, with one of them being the fake issue Multiple Issues: Infinite Identity Countdown to Final Crisis Ad Infinitum: The Introducing. This issue follows on from Exigency Climax: Final Crisis Across Multi-Realities: The Finality, with every DC Hero from every universe introducing themselves to each other... before the next crossover event happens.

Multi-Media

• The Doctor Who Expanded Universe has had multi-media crossover events involving multiple different spin-off works.
  • Time Lord Victorious (2019-22 — intended to be 2019-20, but some works were delayed by the COVID-19 pandemic), which centered on the Eighth, Ninth and Tenth Doctors, and included New Series Adventures novels, Big Finish Doctor Who dramas, comic arcs in both Doctor Who (Titan) and the Doctor Who Magazine comic strip, webcasts, a T-shirt, and two live theatrical events, A Dalek Awakens and Time Fracture.
  • Doom's Day (2023), which was set in a single 24-hour day from the perspective of the assassin Doom, hired to kill the Doctor, and included a webcast, text stories on the BBC website, arcs in both the Titan Doctor Who comic and the Doctor Who Magazine strip, content in the Doctor Who: Lost in Time mobile game, a prose novel, and audio dramas from both Big Finish and BBC Audio.

Mythology and Religion

• Older Than Feudalism: Greek Mythology knows at least two major crossover events: the Argonautica (the story of Jason, the Argonauts, and the Golden Fleece) and the Calydonian Boar Hunt a few years later. Large arc-based events like the Theban Wars and the Trojan War may also count.
• The earliest stratum of Arthurian Legend drew folk heroes and gods from lots of disparate Celtic myths and legends to form King Arthur's court.
• The Æsir-Vanir War, where the two pantheons of Norse gods the Æsir and Vanir (whom some suggest originated from two different religions that was merged) fight and ultimately becomes one tribe, and Ragnarök, where characters from all over Norse mythology meet up to kill each-other.

Professional Wrestling

• The Invasion storyline in the WWE was meant to be this, with top WCW talent (the then WWF had bought out WCW) "invading" WWF. However contract issues meant that many of the WCW's top stars weren't involved.
• Rather than being involved in every aspect of a single company, The Hostile Youth Project was out to invade every North Carolina promotion in 2002.

Tabletop Games

• The Abyssal Plague, a series of Dungeons & Dragons Tie In Novels which started out in the Nentir Vale setting but grew to involve other D&D worlds too, including the Forgotten Realms, Eberron and Dark Sun.
  • The D&D settings Planescape and Spelljammer are made of this trope, explicitly designed to allow travel and storylines across D&D's other universes. While it was implied for years that all D&D games belonged to the same multiverse, these were two official company lines that supported it.
  • The book Die, Vecna, Die had the titular lich escape the Mists, leading the party to fight in Greyhawk, across various planes, and culminating in an attack on Sigil. Canonically, this module is the story reason for the changes from 2nd Ed. to 3rd.
  • The 50th Anniversary adventure, Vecna: Eve of Ruin crosses over Forgotten Realms, Planescape, Spelljammer, Eberron, Ravenloft, Dragonlance, and Greyhawk as heroes and characters fight to stop Vecna, who's now an aspiring Multiversal Conqueror.
• The Old World of Darkness had a few thematic ones toward the end of its line, but an official one with the Time of Judgment series of books, officially ending the old settings.
• Rifts is this to the Palladium systems of games. The setting is of Earth a couple hundred years in the future, after having been transformed into a multidimensional hub, with beings from all over time and space arriving, either by choice or forcibly.
  • More specifically, Palladium ran a series of Sourcebooks called "Minion Wars," detailing a conflict between two different versions of Hell that spilled out across the Megaverse. Sourcebooks were written for several Palladium titles, describing how those specific settings were affected by the war.
• Reality Storm: When Worlds Collide, a crossover between Silver Age Sentinels and Champions.
• The OblivAeon event in Sentinels of the Multiverse, which not only sees villains turn hero (permanently or otherwise), but includes heroes from alternate universes rushing to help fight in the grand finale.
• In Wargames, characters and factions beating the crap of each other is their entire point, but sometimes events in the story get too out of hand and several facions are drawn into the ensuing conflict. These wars are commonly told in special supplements commonly named "Campaign Books". These books usually include the background of the conflict, special rules and scenarios to replicate in the tabletop the battles of the mentioned conflict and the rules of units, soldiers and characters who got involved in said conflict, regardless of faction or allegiance. Sometimes, these camapigns and their resolution gets it's way into the story itself and becomes a part of it, specially in the ficitional wargames.
  • Years ago, Games Workshop hosted events called "World Campaigns" which involved every faction of their main games Warhammer or Warhammer 40,000 and threw them into a war where everyone had someting at stake, with different levels of focus (Usually both Empires being the highest) in the story. These campaigns were to be played by players all around the world and games deciding (usually) the outcome of said wars. Some Campaigns were reinforced by Campagin books like normal campaigns. The most famous are included in their games entries.
    • 40K had campaign suppements way back to 2nd Edition, like Storm of Vengeance, but other, more recent ones are Armageddon and Eye of Terror related to the World campaign of the same name. The most recent ones are The Red Waagh and Shield of Baal series of books and boxed sets wich the firt Series pits the Astra Militarum, and Space Wolves aganist the Orks, and the second the Astra Militarum, Sisters of Battle, Blood Angels and Necrons aganist the Tyranids.
    • Warhammer also had its share of campaigns, usually in the form of "campaign boxes", normally centered in two or three of the factions that included the campaign books and special markers or scenery, all capboard. Some of most famous of these Campaign boxes are Idol of Mork and Tears of Isha. 6th Edition onwards, the campaign box format was dropped in favor of the traditional book, being the most famous campaigns The Shadow over Albion, Storm of Chaos and The Nemesis Crown also World Campaigns (albeit The Nemesis Crown was retconned the istant the campaign ended and Storm of Chaos suffered the same fate in the beggining of 8th Ed., The Shadow over Albion sticked). The most famous (and controversial) of the recent campaigns is the Warhammer: The End Times series of books. The End times tells the story of the final days of the world and the efforts of EVERYONE to stop it or bring it. No one knows for sure if it will stick, but everyone fears that it will. No need to say that it didn't end well.

Webcomics

• In late 2008, Irregular Webcomic! had most of its separate "themes" converge when simultaneous paradoxes occur and the universe imploded. Eventually the characters managed to restart the universe, but most themes suffered a Continuity Reboot in the process.
  • It appears another one is in the works, with several characters being transported to the 1940s, and the recurring Arc Word "Greatness is often linked with insanity."
• Least I Could Do parodied this with the storyline "Ultimate Final Civil War Invasion Crisis Thing", where the gaming webcomics (including Penny Arcade and Ctrl+Alt+Del) are attempting to take out the "straight comedy" comics and reassert their dominance. Receives several lampshades, such as when Faye calls the plot weak, and Rayne counters, "So was a cosmic vampire, but that didn't stop DC."
• When Emily and Tesrin of All Over The House crash-landed in The Life of Nob T. Mouse, it kick-started a crossover that changed both comics permanently.
• The Crossoverlord is one between several superhero webcomics, including Lightbringer, Mechagical Girl Lisa ANT , Mindmistress, Dasien and Dead Debbie from Indefensible Positions. The sequel, Crossoverkill, retains Mindmistress and adds Energize, Yuuki from Sparkling Generation Valkyrie Yuuki, Fusion, Captain Perfect from Bad Guy High, Majestic Knight and Magellan Hoodoo.

Web Original

• Deviantart Secret Wars
• TGWTG Year One Brawl, Kickassia, Suburban Knights, and To Boldly Flee from the people at Channel Awesome.
• These have become the main storyline in I'm a Marvel... And I'm a DC, as is to be expected in a meta series for both Marvel and DC. Having Deadpool around means that inter-series continuity is now lampshaded.
• The blogosphere side of The Slender Man Mythos has had a few. Some examples include the Winter Solstice story in Observe and Terminate and A Hint of Serendipity, and the Wedding crossover from Take The Myth.
• The Fear Mythos, a spin-off of The Slender Man Mythos, had one early in its existence: The Birth of the Manufactured Newborn. It involved four different blogs intertwining their stories: The Hunter, The Devil and God Are, They Sought It With Thimbles, and Hidden in the Trees. The crossover involved a conspiracy by the Fears to birth a new one into their ranks, while the human characters either try to stop them or try to help them.

Western Animation

• Dexter's Laboratory: Last But Not Beast had the Dexter, Monkey and Justice Friends segments connected via the giant monster destroying Japan. The Monkey segment even skips its usual opening credits to continue the story.
• Turtles Forever: It deals with the 2000 Shredder returning from his exile, taking over the 1980s Shredder's Technodrome, and, after learning of the TMNT Multiverse, he plans to go conquer it, until he learns that there are teams of TMNT in each and every reality. He goes after the original Mirage Turtles in order to destroy all the Turtles, and three seats of Turtle Teams set off to stop him.
• Hanna-Barbera did this with the "Council of Doom" storyline in Space Ghost with Space Ghost eventually meeting Moby Dick, Mighty Mightor, Shazzan, and The Herculoids. Sometimes, the Cartoon Network (and later, Boomerang) would show the whole thing.
  • The later Space Stars series did this at the end of each show with a "Space Stars Finale" which features a team up of characters from two or more of the show's segments (Teen Force, Space Ghost, The Herculoids, and Astro and the Space Mutts).
• Another Hanna-Barbera example would be Yogi's Ark Lark which by definition featured characters joining together to deal with a crisis. Except the crisis in question wasn't a comic book level event as much as the planet has too much pollution kind.
• The Phoenix Saga of X-Men: The Animated Series was a borderline example. Although there were no actual team ups, it used appearances of other Marvel Comics characters to emphasise the seriousness of the whole thing. Captain Britain and Doctor Strange were seen reacting to the Phoenix and Spider-Man (albeit only his silhouette and his hand) and War Machine were seen protecting civilians in New York. In the sequel, the Dark Phoenix Saga, Doctor Strange briefly appeared again, along with Thor, a Watcher and Eternity.
• A made-for-TV animated movie called The Man Who Hated Laughter brought together a big group of newspaper comic strip characters — Blondie, Popeye, Beetle Bailey, Hi and Lois, Snuffy Smith — who are ultimately saved from a comics-hating villain by the combined forces of a group of newspaper adventure strip heroes (Mandrake the Magician, Flash Gordon, Prince Valiant, The Phantom, and Steve Canyon). All the characters are owned by King Features Syndicate.
• Hurricane Flozell blew her way into all three Seth MacFarlane shows, The Cleveland Show, Family Guy and American Dad! culminating in the final scene of the American Dad episode where Cleveland, Stan, and Peter have a standoff with guns.
• The feature-length special Rudolph and Frosty's Christmas in July by Rankin Bass, which brought back several characters from all of their holiday specials and many of the voice actors from the previous specials as well. It involves Rudolph, Frosty, and Santa trying to stop an evil wizard named Winterbolt. It also contains a bounty of Continuity Porn, with callbacks to other previous specials such as Santa Claus is Comin' to Town, Rudolph's Shiny New Year, and Frosty's Winter Wonderland (with the notable exception of The Year Without a Santa Claus, leaving the poor Miser Brothers snubbed).
• Spider-Man: The Animated Series: While the show had many crossovers, the series had two of this nature near the end of it's run. "Secret Wars" which saw Spider-Man drafted to be a leader in a literal battle of good vs evil where he picks the Fantastic Four, Storm, Captain America, Black Cat and Iron Man to help take on the likes of Dr. Doom, Dr. Octopus, The Lizard, Alister Symthe and Red Skull. The final arc of the series, "Spider Wars", saw him teaming with various Spider-Men from different alternate universes (one with six arms, one with Doc Ock's metal tentacles, one who was a billionaire and built his own tech, one who didn't have any powers, and one who was the Scarlet Spider) to stop Spider-Carnage, a murderous version of Spider-Man who fused with the Carnage symbiote.
• Teen Titans Go! vs. Teen Titans features the 2013 Teen Titans meeting up with their 2003 counterparts to do battle against both Go!Trigon and a freshly resurrected 2003 Trigon. Multiple incarnations of Teen Titans throughout the multiverse are eventually summoned to do battle with this new threat alongside the two main teams.
• The premise of Pibby, as shown in the trailer, is that an Eldritch Abomination is destroying several different cartoon shows (fictional and real, the latter all owned by Warner Bros.) and killing their casts. Pibby is forced to dimension-hop into these shows and meet with other characters in the hopes of stopping it.

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