Crisis on Infinite Earths

"Crisis on Infinite Earths" is a 40 issue Pre-Crisis and a 59 issue Official/Unofficial Crisis crossover event and an eponymous 12-issue American comic book limited series (identified as a "12-part maxi-series"), produced by DC Comics in 1985 to simplify its then 50-year-old continuity. The series was written by Marv Wolfman and illustrated by George Pérez (pencils/layouts), along with Mike DeCarlo, Dick Giordano, and Jerry Ordway (who shared inking/embellishing chores). The series removed the concept of the Multiverse in the fictional DC Universe, and depicted the deaths of such long-standing superheroes as Supergirl and the Barry Allen incarnation of the Flash. As such, it is one of the most important events in the DC Universe, and continuity in the DCU is typically divided into pre-Crisis and post-Crisis periods.

The title of the series was inspired by earlier crossover stories involving the multiple parallel Earths of the Multiverse, such as "Crisis on Earth-Two" and "Crisis on Earth-Three", but instead of lasting two to five issues and involving members from many superhero teams from many parallel worlds, it involved virtually every significant character from every parallel universe in DC's history. It in turn inspired the titles of four subsequent DC crossover series: Zero Hour: Crisis in Time! (1994), Identity Crisis (2004), Infinite Crisis (2005–2006), and Final Crisis (2008).

Continuity issues
Prior to Crisis on Infinite Earths, DC publications were notorious for continuity problems. No character's back story within the comic books was entirely self-consistent and reliable. For example, DC's oldest superhero character, Superman, the lone survivor of the destroyed planet Krypton, originally could not fly (he could instead leap over an eighth of a mile), and his powers came from having evolved on a planet with stronger gravity than Earth's. Soon, he was depicted as able to fly and his powers were explained as coming from our solar system's yellow sun. A more complex origin story was invented. In time, his career was altered to include early exploits as Superboy. More survivors of Krypton were introduced, including Supergirl, a dog named Krypto, the inhabitants of the bottled city of Kandor, and others. This further watered down the original concept: that the character was the sole survivor of his planet's destruction.

Issues also arose regarding the ages of characters. Batman, an Earth-born human without superpowers, retained his youth and vitality well into the 1980s despite having been an active hero during World War II. His sidekick, Robin, took over thirty years in real time to graduate from high school.

Characters such as the Flash, the Atom, and Green Lantern often featured conflicting story lines. Origins and even powers differed between tales, depending on the writers.

Multiverse fixes
Little attempt was made at first to offer in-universe explanations of the conflicts. Problems of this sort began to be addressed in the 1961 story "Flash of Two Worlds", which featured a meeting between Barry Allen, the then-currently published version of the Flash, and Jay Garrick, the version originally published by the company. The meeting was made possible by the introduction of the idea of two parallel worlds: Earth-One, the contemporary DC Universe which had been depicted since the advent of the Silver Age; and Earth-Two, the parallel world where the Golden Age events took place, and where the heroes who were active during that period had aged more or less realistically since that time.

This idea was eventually expanded into the concept of a multiverse, including such worlds as Earth-Three, which was an "opposite" world where heroes were villains and historical events happened in reverse of how they occurred in real life (e.g., President John Wilkes Booth being assassinated by an actor named Abraham Lincoln), and Earth Prime, which was ostensibly the "real world" and used to explain how real-life DC staffers (such as Julius Schwartz) could occasionally appear in comics stories, and so forth. If something happened outside current continuity (such as the so-called "Imaginary Stories" that were a staple of DC's Silver Age publications), it was explained away as happening on a parallel world, a premise not dissimilar to the company's current Elseworlds imprint.

As the volume of published work within the DC Universe became larger and as the original stories of characters receded in time, the task of reconciling plot points grew. The burden of keeping track of differing versions of a variety of characters proved taxing for DC's writers.

Crisis resolution
Crisis was originally conceived to be a celebration of DC's 50th anniversary; however, Marv Wolfman and Len Wein saw it as a chance to clean up DC's rather convoluted continuity (which was thought to have put many new readers off buying DC titles) that had built up over time. The term "Crisis" was a word used frequently in DC Comics of the time, as it denoted an inter-dimensional crossover, such as the yearly Justice League/Justice Society crossovers that began with "Crisis on Earth-One".

Wolfman came up with an idea that would reach across the entirety of the DC Universe and its half-century of history. The groundwork for Crisis was laid over the year preceding its publication as one of the chief characters of the series, the Monitor, was introduced into various comics. In these original appearances, the Monitor was portrayed as a shadowy figure and a potential villain. His face was never shown, perhaps to imply that he might be an established DC villain, and his most common appearance was as a source of technology or information for various villains in the DC Universe.

According to writer Steve Gerber, Crisis on Infinite Earths "got virtually no promotion. I mean, it's hard to think about that now, because of the reaction to the book and the amount of coverage it's gotten in the fanzines - but if you try to think back, how many handouts did you see? How many posters did you see in people's windows? How much information was really distributed to the press and how much was gotten just by individual reporters going to Marv Wolfman and [Crisis artist] George Pérez?" Despite this, the series was highly successful from a marketing standpoint, generating renewed interest in the company's books, enticing readers with the tagline that "the DC Universe will never be the same." Along with Alan Moore's Watchmen and Frank Miller's Batman: The Dark Knight Returns, it contributed to the commercial and creative revitalization of DC Comics after years of being dominated in the market by rival publisher Marvel Comics.

Crisis also helped popularize the formula of the line-wide "crossover" comic book series, a concept deployed previously in Marvel's Contest of Champions (1983) and Secret Wars (1984). Since 1985, superhero publishers such as DC and Marvel have had frequent "summer crossover" series designed to tie many of their comic book titles together under a single storyline.

Plot summary
The story introduces readers to two near-omnipotent beings, the good Monitor and the evil Anti-Monitor, who had been created as a result of the same experiment that created the Multiverse. The Monitor made cameo appearances in various DC comic book series for two years preceding the publication of the series. At first, he appears to be a new supervillain, but with the onset of the Crisis, he is revealed to be working on a desperate plan to save the entire Multiverse from destruction at the hands of the Anti-Monitor. The Crisis series depicts the efforts of DC Comics' superheroes to stop the Anti-Monitor's plan to reign supreme as the ultimate ruler of all. Under the initial guidance of the Monitor, a select group of heroes is assigned to protect massive "tuning forks" designed to merge the surviving Earths into one that could be protected from the antimatter that has already annihilated untold numbers of alternate Earths. Eventually, the conflict grows and nearly every DC hero becomes involved in the battle.

The Monitor is murdered by his own assistant, Harbinger, while one of her duplicates is temporarily possessed by one of the Anti-Monitor's "shadow demons." However, he expects the attack and allows it to happen so that his death will release enough energy to project the last five parallel Earths (the homes of the known DC Universe) into a temporary Limbo universe. In-between, the Anti-Monitor recruits Psycho-Pirate to his cause, (who at the time had not yet been entered into the Limbo universe following the absorption of Earths 1 and 2 into the Limbo universe), and even temporarily infuses part of his power into him to control the other three Earths (4, S, and X). This fails when all five Earths are now inside the Limbo universe. Harbinger then recruits a group of those five remaining Earths' heroes to lead an assault on the Anti-Monitor in the antimatter universe under her guidance, using Alex Luthor's antimatter powers to open a portal between the Limbo and Antimatter universes Alexander Luthor, Jr., and Pariah acting as the guide to track down the Anti-Monitor at his fortress, where he was using a converter powered by stellar energy to force the last 5 earths together, thereby destroying them once and for all (given he learned what the Monitor had done to save those worlds and their respective universes). The heroes triumph by destroying the converter, and he's forced to retreat,after a pitched battle with Supergirl leaves him desperately wounded and Supergirl dying minutes later.

This lull in the war provides some breathing room for the heroes but the various supervillains join forces under Brainiac who murders Alexei Luthor of Earth-Two for trying to take leadership citing the villains don't need two Luthors to lead them since he had also recruited the Earth-One Lex Luthor to his cause as well as co-leader to conquer the Earths, the Flash (Barry Allen) in the interim dies stopping the Anti-Monitor's backup scheme of destruction by using an antimatter cannon to penetrate the Limbo universe and destroy the surviving five Earths now partially merged by using his speed powers to cause the energy to compact inside thereby destroying the cannon. Furious but damaged yet again the Anti-Monitor swears to stop the heroes at the dawn of time. The Spectre then halts the hero/villain conflict warning that the Anti-Monitor is traveling to the beginning of time to prevent the Multiverse's creation, and the heroes and villains join forces in response with the heroes traveling to stop the Anti-Monitor and the villains traveling to the planet Oa in antiquity to prevent the renegade scientist Krona from performing a historic experiment that would allow the Anti-Monitor to succeed in his efforts. The premise is that the past may be changed only by going to the beginning of time.

The villains fail, and Krona proceeds with his experiment, as the heroes are captured by the Anti-Monitor (lying in wait as Alex Luthor opens the portal between the Positive and Anti-Matter universes), with their energies used so that Krona would see his hand instead, thereby insuring victory for the Anti-Monitor (given he expended much of his energy to travel that far back in time), as his universe would reign supreme. However, the Spectre (supported by Earths' magically powered heroes in the Positive Universe), battles with the Anti-Monitor, thereby creating an energy overload that shatters space and time. A single universe is created and all the superheroes return to a present-day reality where the various elements of the five Earths were fused into one single Earth, with no one except the people present at the dawn of time remembering the original reality.It is never clear whether the multiverse was merged at the instant the heroes went back in time, or whether the multiverse never existed at all.

The now gigantic Anti-Monitor attacks one last time, transporting Earth to the Anti-Matter universe, and summons a massive horde of shadow demons. However, he falls to a carefully planned counter-attack, culminating in a battle with Kal-L (the Earth-Two Superman), Alexander Luthor of Earth-Three, and Superboy of Earth-prime, with some unexpected last-second help from the New Gods' adversary, Darkseid. The Anti-Monitor is increasingly damaged & mangled in this final battle, and is finally just a flaming head. As the Anti-Monitor crashes into a star and dies, Alex sends himself, Earth-Two Superman, Earth-Two Lois Lane, and Earth-Prime Superboy into a paradise reality.

The aftermath of the Crisis plays out a few pages later, including Wally West becoming the new Flash. The final page shows the Psycho-Pirate, who was now imprisoned in Arkham Asylum, talking to himself in a monologue:

I'm the only one left who remembers the Infinite Earths. You see, I know the truth. I remember all that happened, and I'm not going to forget. Worlds lived, worlds died. Nothing will ever be the same. But those were great days for me... I had a good friend in the good old days, really. He was the Anti-Monitor. He was going to give me a world to rule. Now he's gone, too. But that's okay with me. You see, I like to remember the past because those were better times than now. I mean, I'd rather live in the past than today, wouldn't you? I mean, nothing's ever certain anymore. Nothing's ever predictable like it used to be. These days... y-you just never know who's going to die... and who's going to live.

Possible alternative ending
According to George Pérez in a Wizard magazine interview in 1994, Chris Claremont suggested that Superman of Earth-One dies in the final battle with the Anti-Monitor in issue #12. After the Anti-Monitor was destroyed for good, Kal-L from Earth-Two realizes that he is now alone, without his Earth, without his Lois, and now the new single Earth is without a Superman. Then he remarks, "Don't need this anymore," and brushes the white dye off his hair and other make-up that he apparently used to make himself look aged. The other heroes are surprised by this and Kal-L simply explains that he had stopped aging when he reached the peak of his powers. He returns with the other heroes to the new post-Crisis Earth, taking the place of the Earth-One Superman.

If this idea had been used, then The Man of Steel would have marked the return of the "Original Super-Hero", as Kal-L (now switched to Kal-El) begins his life on the post-Crisis Earth, which is similar to his old life, but with distinct differences. Despite this "culture shock," Kal-L endures and is given a new lease on life by being deposited back to the early days of the modern heroic age of the post-Crisis Earth. However, this was discarded when the John Byrne version of The Man of Steel was planned.

Animal Man (of Grant Morrison)
Roger Hayden (Psycho-Pirate) shows up again in Grant Morrison's run on Animal Man, imprisoned in Arkham Asylum. He ends up releasing characters destroyed during the Crisis back into the world. Many of these characters come to realize that they are just characters in a comic book. After an intervention by Animal Man, Hayden, seemingly happy, fades away into nothingness due to the strain from releasing all the forgotten characters, removing him from reality and heading into Limbo, where DC characters go when not being written about. James Highwater, a Native American physicist, is left to wear the Medusa Mask and keep the forgotten worlds contained. The other staff members come to accept Highwater as a patient, stymied by the fact that the mask had bonded to his face and required Highwater to be fed introvenously.

Later writers (most notably John Ostrander in Suicide Squad-themed crossover "The Janus Directive") would reveal that Highwater would soon lose the Medusa Mask under mysterious circumstances. Psycho Pirate would not be seen again until after the events of Zero Hour, with his memories of the Crisis apparently erased by the timeline changes made during Zero Hour. However, his memories of the multiple earths would be restored in Joker's Last Laugh and would be a main plot point in Infinity Crisis.

Official and Unofficial Tie-in issues: Pre-Crisis

 * Action Comics #560 & #564
 * All-Star Squadron #40
 * Amethyst (vol. 2) #2
 * Batman #384
 * Batman and the Outsiders (vol. 1) #14-15
 * Blue Devil #5
 * DC Comics Presents #76 & #78
 * Detective Comics #551
 * The Flash #338-339
 * The Fury of Firestorm #28
 * GI Combat #274-275
 * Green Lantern (vol. 2) #173, #176 & #178
 * Infinity, Inc. #8
 * Jonah Hex #90
 * Justice League of America #232 & #234
 * The New Teen Titans #21 & Annual #2 Issue #21 (July 1982) is the first appearance of the Monitor.
 * Swamp Thing #30-31
 * Superman #402-403
 * Tales of The Legion of Super-Heroes'' #317, #319-320
 * Tales of The Teen Titans #47 & #58
 * Vigilante #14
 * Warlord #91
 * Wonder Woman #321 & #323
 * World's Finest Comics #311 & #314 Issue #314 (April 1985) The last Pre-Crisis and first Crisis story arc.

Official and Unofficial Tie-in issues: Crisis

 * All-Star Squadron #50-56
 * Amethyst (vol. 2) #13
 * Batman #389-391 Issues #389-391 Not bannered as a Crisis Crossover.
 * Blue Devil #17-19 Issue #19 Not bannered as a Crisis Crossover.
 * DC Comics Presents #78, #86-88, #94-95 Issues #78, #94-95 Not bannered as a Crisis Crossover.
 * Detective Comics #556-558 Issues #556-558 Not bannered as a Crisis Crossover.
 * The Fury of Firestorm #41-42
 * Green Lantern (vol. 2) #194-198 Issues #196-197 Not bannered as a Crisis Crossover.
 * Infinity, Inc. #18-25, Annual #1 Issue #25 Not bannered as a Crisis Crossover.
 * Justice League of America #244-245, Annual #3
 * Legion of Super-Heroes (vol. 3) #16, #18 & Annual #1 Issue #16 and Annual #1 Not bannered as a Crisis Crossover.
 * Losers Special #1 (note:first official post-Crisis story)
 * The New Teen Titans (vol. 2) #13-14
 * The Omega Men #31, #33 Issue #33 Not bannered as a Crisis Crossover.
 * Superman #413-415 Issue #413 Not bannered as a Crisis Crossover.
 * Swamp Thing (vol. 2) #44, #46 Issue #44 Not bannered as a Crisis Crossover.
 * Vigilante #22 Issue #22 Not bannered as a Crisis Crossover.
 * Wonder Woman #327-329

Tie-in issues: Post-Crisis

 * All-Star Squadron #58-60
 * Green Lantern (vol. 2) #199-200
 * Infinity, Inc. #27, #30
 * Justice League of America #246
 * Last Days of The Justice Society Special #1
 * The Legend of Wonder Woman #1-4

Post-Crisis
Because of the extensive and substantial changes that Crisis on Infinite Earths implemented on many titles published by DC Comics, the series became a defining and critical moment in DC Comics' long-standing continuity. Characters and other elements established before the series, especially those eliminated by it, were referred to as pre-Crisis, while revised ones were considered post-Crisis. As a result, the series and its events eventually became known simply as "The Crisis", an informal title that would persist among fans, readers, and even the DC editorial staff, for almost 20 years.

However, with the advent of the 2005–2006 mini-series Infinite Crisis, another continuity-altering storyline, pre- or post-Crisis alone is no longer a definitive identifier; it is now necessary to make clear which Crisis one is referring to. Recent terms have been adopted by both fans and DC Comics when referring to anything after Infinite Crisis, such as "post-Infinite Crisis", "One Year Later", or simply "New Earth". The terms "post-CIE," referring to Crisis on Infinite Earths, and "post-IC," referring to Infinite Crisis, have also been used to avoid confusion between the two storylines.

Crisis on Infinite Earths was used by DC as an opportunity to wipe much of its slate clean and make major changes to many of their major revenue-generating comic book series. Frank Miller's revamp of Batman with Batman: Year One, George Pérez's relaunching of Wonder Woman in Gods and Mortals, and John Byrne's reboot of Superman in The Man of Steel all took place shortly following Crisis on Infinite Earths, and changed substantial elements of the characters' backstories. The Green Lantern title was also changed to Green Lantern Corps, chronicling the adventures of a group of Green Lanterns led by Hal Jordan and stationed on Earth.

Several other titles which were not significantly retconned were taken in very different directions following Crisis on Infinite Earths. However, to give readers breathing room, these revamps were delayed for a year so that they could be tied into DC's next "big event" storyline, "Legends". The Flash was relaunched starring a younger main character, the previous Flash's sidekick, Kid Flash (Wally West). The Justice League of America title was canceled, to be replaced by a new series entitled simply Justice League, featuring a new cast drawn from what had been different universes in DC's pre-Crisis multiverse. A new Suicide Squad title was launched, and Captain Marvel was given his own new mini-series to establish his new post-Crisis origin.

Acknowledgment of the Crisis
Since Crisis on Infinite Earths created a new, singular universe with a new back-history, the Crisis event itself (as told in the limited series) is still part of it, with various "revised" DC Universe characters often referencing a past event called "Crisis". In this history, the heroes opposed the Anti-Monitor, who sought to destroy the (single) positive-matter universe in favor of his anti-matter universe. Supergirl did not die as she did not exist in this new universe, but Barry Allen indeed sacrificed his life to save the universe. What is not known by the heroes is that there once existed a multiverse, and that's what they saved, instead believing they saved their single universe from destruction, given their memories from the dawn of time battle in Crisis #10 had been subsequently erased over time.

Although the characters who were present at the epic battle at the dawn of time (Crisis on Infinite Earths #10, "Death at the Dawn of Time") — Psycho-Pirate, Lady Quark, Harbinger, and Pariah — were initially treated as exceptions, this idea did not stick, given both Lady Quark and Pariah's worlds actually existed in the single universe, albeit differently, and both were destroyed during the single universe "Crisis". There have been occasional references to the event. A 2002 storyline in the Supergirl comic book saw the original pre-Crisis Supergirl landing on post-Crisis Earth, for example, and established that the Spectre, being able to see across dimensions and timelines, is aware that the Crisis occurred. In addition, Grant Morrison's run on Animal Man, heralded for its deconstruction of the concept of the comic book, initiated a "Second Crisis" in which characters such as the original Crime Syndicate of America from Earth-Three came back to life thanks to the Medusa Mask owned by the Psycho-Pirate, who remembered the original Crisis. Per Degaton is aware of the pre-Crisis timeline, as he told the JSAs of the present and of 1951 that he would retcon them out of existence the same way the Huntress of Earth-Two was. With the Fourth World existing outside the Multiverse proper, Darkseid has also acknowledged the events of the Crisis. Members of the Green Lantern Corps were also aware of the Crisis, even though none participated in the battle at the beginning of time. Corps member Ch'p, the only Earth-One character to have his timeline completely erased by the Crisis, was nonetheless recognized by his fellow Green Lanterns. John Constantine is also aware of the Crisis, as seen in Swamp Thing (vol. 2) #70. In the Planetary special Planetary/Batman: Night on Earth, it was implied that Elijah Snow had somehow temporarily left the Wildstorm universe to witness the Crisis. Finally, during the Joker: Last Laugh crossover, the Joker refers to the lack of "anti-matter auroras" and "blood-red skies" during his rampage, declaring that "Every other crisis gets funky mood lighting!"

Deaths during Crisis
The following DC characters were explicitly shown to have died during Crisis on Infinite Earths:
 * Alexander Luthor, Sr. of Earth-3 and wife Lois Lane Luthor
 * Alexei Luthor of Earth-2
 * Angle Man
 * Anti-Monitor
 * Aquagirl (Tula)
 * Bug-Eyed Bandit
 * Clayface (Matt Hagen)
 * Crime Syndicate of America
 * Dove (Don Hall)
 * Farmer Boy (identified as "Flower") of Sgt. Rock's Easy Company
 * Flash (Barry Allen)
 * Green Arrow of Earth-2
 * Huntress of Earth-2
 * Icicle (Joar Mahkent)
 * Immortal Man
 * The Justice Alliance of Earth-D (in Legends of the DC Universe: Crisis on Infinite Earths [1999])
 * Kid Psycho of the Legion of Super-Heroes
 * Kole
 * Lori Lemaris
 * Lord Volt of Earth-6
 * The Losers (Johnny Cloud, Gunner, Sarge, Captain Storm) (Note: in Losers Special #1, their post-Crisis deaths are attributed instead to a last stand of sorts vs. a Nazi regiment, their spirits taken away by Johnny Cloud's spiritual Native American spirits, instead of being attacked by the Anti-Monitor's Shadow Demons)
 * Maaldor the Darklord
 * Mirror Master (Samuel Joseph Scudder)
 * Monitor
 * Nighthawk
 * Prince Ra-Man
 * Princess Fern of Earth-6
 * Psimon
 * Robin of Earth-2
 * The JLA-created Shaggy Man
 * Starman (Prince Gavyn)
 * Sunburst
 * Supergirl of Earth-1
 * The Ten-Eyed Man
 * Wonder Woman of Earth-1 (of note:her body was devolved by the Anti-Monitor's energy in his weakened state in Crisis #12, thereby reversing her to clay and her Amazon sisters' history as well to send them back to the isle of Themyscira (Legend of Wonder Woman #1-4) (this laid the groundwork for George Perez' reintroduction of Wonder Woman in the post-Crisis continuity).

Some of the deceased characters have since reappeared:
 * Gunner showed up alive and well in the comic Creature Commandos (albeit with cybernetic enhancements).
 * A Hawkman issue revealed that Nighthawk is believed to have died under different circumstances, and was instead a reincarnation of the Golden Age Hawkman, post-Prince Khufu.
 * The subsequent reboot of Superman's titles erased Lori Lemaris' death from continuity. She was reintroduced as not being wheelchair-bound, but with a more rational "leg-changing" ability, according to situations.
 * The Crime Syndicate was brought back three times: first as Qwardians the Justice League fought years ago, then post-Zero Hour as people from the Earth of the Antimatter Universe, and finally as the Crime Society of America in 52 and Countdown (of note: the Crime Society was created more as a foe to the recreated Earth-2's JSI, and not directly related to the Crime Syndikate of the Antimatter universe)
 * James Robinson's Starman comics revealed that Prince Gavyn's spirit actually survived and bonded with Will Payton, thereby creating this new Starman.
 * Psimon was resurrected.
 * Mark Merlin, human host of Prince Ra-Man, did not die along with him, being instead "freed" from his possession.
 * After the events of Infinite Crisis and 52, Earth-Two (albeit a different version) was resurrected with many of the characters that had died in Crisis alive and well on the new Earth-Two.
 * Twenty-three years after his landmark death in the original Crisis, Barry Allen returned to the DC Universe on the last page of Grant Morrison's Final Crisis #2.

New characters and changes
Several new characters were introduced in Crisis. The Monitor's assistant, Harbinger, and scientist Pariah played major roles in the story. Lady Quark was introduced as a survivor of one of the destroyed worlds. A new Doctor Light, this time heroic and female, was introduced. The former Charlton Comics characters — notably Blue Beetle II — were introduced to the DC Universe.

After the Crisis, former Kid Flash Wally West took over the mantle of his predecessor, the Flash. Jonah Hex was transported to a post-apocalyptic future, but this did not prove popular and subsequent stories brought him back to the Wild West. The JSA member Wildcat was replaced by his god-daughter, Yolanda Montez, and became a member of Infinity, Inc., alongside Rick Tyler Hourman II and Dr. Beth Chapel Dr. Midnight. The Guardians of the Universe departed for an unknown dimension, and the Green Lantern Corps was reorganized, with Hal Jordan leading a team of Green Lanterns based on Earth. The surviving Justice Society members departed for Limbo (alongside Wildcat Ted Grant) to stop Ragnarok from happening due to Hitler's using of the Spear of Destiny to open a link between our world and Asgard during Ragnarok.

Continuing continuity issues
The changes made in the wake of Crisis were not implemented consistently. The series was published over the course of a year, with ongoing series continuing simultaneously. In addition, several stories set in the previous continuity were published following the series' final issue. Initially, characters who were present at the final battle at the dawn of time remembered their original histories until their post-Crisis histories were fully established, a process that sometimes required years to completely play out. Furthermore, revamped or relaunched versions of titles debuted at different times, with DC continuing to feature old versions of characters until new versions were launched, sometimes a year or more later. As a consequence, a series intended to streamline DC continuity introduced additional complexities.

Several characters such as Hawkman, Donna Troy, and Power Girl saw their origins complicated by the changes implemented by the Crisis and the various reboots of characters. The Superman line saw particular continuity issues regarding its supporting cast. In an effort to return Superman to his special status as the "last son of Krypton" DC had used the Crisis and the Man of Steel limited series to eliminate most of the Kryptonian supporting characters. For Supergirl this was not a major problem initially since the character had died in the Crisis. However, later writers would bring the character back using various explanations ranging from her being a shapeshifting alien to her being an angel. Power Girl, originally introduced as a cousin of Superman still existed however. With the mandate to reduce the number of Kryptonians in the DCU, her origin was changed to being a descendant of ancient Atlanteans who mistakenly believed herself to be Superman's cousin. Donna Troy's origin was similarly complicated by Crisis. Originally she had been an orphan who Wonder Woman raised on Paradise Island. However, Crisis had eliminated Wonder Woman from history; the character would not debut in the new DC Universe until the next year. Her origin was therefore rewritten to involve the Greek Titans.

Other inconsistencies include:
 * Action Comics #590: The narrator recounts exactly how Chemo is destroyed on Earth-4 by the Negative Woman in Crisis on Infinite Earths #9, stating, "Weeks ago on a parallel earth that no longer exists," and goes on to specify how he survived when all the Earths merged into one single Earth at the end of the Crisis.
 * Superman #8: Superman was referred to mistakenly as Superboy (the young Clark Kent from the Time Trapper's pocket universe) by the Legion of Super-Heroes. He recalls meeting a Superboy (Earth-Prime) during the Crisis and that he was not around long enough to make any enemies. The problem is that the Earth-Prime Superboy should not be remembered.
 * Legion of Super-Heroes #38: During the mourning of Superboy, a statue of Supergirl is seen. The statue, like the others in the background, is made in dedication to fallen Legionnaires. The Supergirl statue would be removed by issue #51 when DC enforced her nonexistent status.

The Crisis had also been intended to eliminate the multi-verse. All stories were now supposed to be set on a unified new Earth. However, as time went on many creators found the idea of alternate universes and timelines to be too interesting to abandon.

Relationship to other crises and possible nullification
At the 2008 New York Comic Con, Dan DiDio described how Crisis on Infinite Earths was the first of a trilogy of "Crisis" limited series that showed different stages in the development of the DC Multiverse. Crisis on Infinite Earths represented the "death of the multiverse"; Infinite Crisis, the "rebuilding of the multiverse"; and Final Crisis, the "final saga of the multiverse".

However, on October 2, 2011 in his Facebook page Dan DiDio seemed to imply that Crisis On Infinite Earths, Infinite Crisis, and Final Crisis did not occur in DC's New 52 universe. According to John Lichman's October 4, 2011 UGO "DC New 52 Timeline So Far" this was to clarify the early statement by Dan DiDio of "Brace yourself, but after further review, there have been no Crisis events in the New DCU."

Spin-offs
There have been a number of spin-offs and Tie-ins.

Legends of the DC Universe: Crisis on Infinite Earths
An untold story from Crisis on Infinite Earths was published in February 1999 as a special in Legends of the DC Universe: Crisis on Infinite Earths #1, written by Crisis writer Marv Wolfman, with art by Paul Ryan and Bob McLeod. It took place during and after Crisis on Infinite Earths #4. It featured the only appearance of Earth-D.

The Flash of Earth-D, Tanaka Rei, was a Japanese man who idolized Barry Allen, whose stories only existed in comic books. Rei was inspired by Allen to become the Flash, much like Allen was inspired to become the Flash by his idol, Jay Garrick. Allen and Rei met during the Crisis on Infinite Earths when Barry was coming back from the 30th century and arrived in the wrong universe. As that earth was under attack by the shadow demons, Barry called on the Justice League and Rei called on the Justice Alliance, his world's version of the Justice League. They built a cosmic treadmill and made an evacuation. The Justice League left, but 39 seconds later, Earth-D perished.

DC Retroactive: Superman - The '80s
Another untold Crisis-related story by Wolfman was published in August 2011 as part of the DC Retroactive series. Illustrated by Sergio Cariello and Curt Swan and set in 1984, Superman - The '80s #1 tells of Destiny showing the pre-Crisis Superman images of future disasters, such as No Man's Land, Identity Crisis, his own death, and the death of Supergirl during the forthcoming Crisis. Superman vows to fight on despite the grim future, and Destiny—who reveals herself as Harbinger—and the Monitor later discuss the hero.

Action figures
To commemorate the 20th anniversary of Crisis on Infinite Earths, DC Direct issued a series of Crisis action figures. However, due to quality-control problems, DC Direct recalled the toys and asked retailers to cut off the heads and ship them back to DC Direct. They were re-released on June 28, 2006.

The first wave included action figure representations of Earth-2 Robin, Supergirl, the Monitor, Harbinger, and Psycho-Pirate. The second wave included action figure representations of the Flash (Barry Allen), Earth-2 Superman, the Anti-Monitor, Lex Luthor, and Brainiac. The third and final wave included action figure representations of Earth-Prime Superboy, Batman, a Weaponer of Qward, Earth-2 Huntress, and the female Dr. Light.

Novelization adaptation
iBooks, Inc., under the distribution of Publishers Group West, adapted the comic book miniseries as a novelization with one of its writers, Marv Wolfman. The whole event was narrated by Barry Allen himself. The hardcover version was released in April 2005 (ISBN 1-5968-7290-X) and the paperback was released in February 2006 (ISBN 1-5968-7343-4). Cover art was done by George Pérez and Alex Ross.

HeroClix expansion
On February 28, 2008, a DC Comics HeroClix set entitled "Crisis" was released.

Audiobook adaptation
GraphicAudio (who had previously done audiobook versions of Infinite Crisis and 52) released an audiobook version of Crisis on Infinite Earths in May 2009. As with their previous DC story adaptations, it was based on the novelization rather than the comic.

Collected editions

 * Crisis on Infinite Earths #1-12 (April 1985 – March 1986) was collected in hardcover (December 1998; ISBN 1-56389-434-3) and trade paperback (January 2001; ISBN 1-56389-750-4) editions, with original cover art by George Pérez and Alex Ross.
 * Official Crisis on Infinite Earths Index (March 1986) was released as a one-shot publication providing a detailed description of each issue in the series, a list of alternative Earths, and a history of the Multiverse concept.
 * Official Crisis on Infinite Earths Cross-Over Index (July 1986) was released as a one-shot publication providing summaries of every comic book issue connected to the Crisis storyline, descriptions of alternative Earths, and a list of every character that appeared in the Crisis series.
 * Crisis on Infinite Earths: The Absolute Edition (November 2005; ISBN 1-4012-0712-X) was released as an oversized, slipcased, hardcover edition. The first volume reprints the limited series and the second volume provides extras, including scripts, commentaries, retrospectives, and also reprints the two indexes.

Parodies and homages

 * Blackthorne Comics published the two-issue mini-series Freak-Out on Infant Earths in 1987.
 * Marvel Comics' Mighty Mouse #4-5 (1991) were titled "Mices on Infinite Earths", and had Mighty Mouse meeting Mighty Mousette and helping the Minotaur, Harebinger, and Piranha fight the evil and powerful Anti-Minotaur. George Pérez drew the cover of issue #4, parodying Crisis on Infinite Earths #7, and issue #5, parodying Crisis on Infinite Earths #12.
 * The Crisis, along with other crossovers and "event" comics, was parodied by Simpsons Comics in the Radioactive Man series. Radioactive Man #679 (September 1994), written by Steve Vance, is entitled "Who Washes the Washmen's Infinite Secrets of Legendary Crossover Knight Wars?" In one issue, Radioactive Man also mentions a "Secret Crisis on Erstatz Earths".
 * MAD Magazine #448 provided a review of the fictional "Infinite Secret Crisis on All Earthly Worlds", which sought to solve the continuity problems by killing absolutely everyone, in alphabetical order.
 * Many images and themes from Crisis on Infinite Earths are repeated in JLA/Avengers, written by Kurt Busiek and pencilled (as was Crisis) by George Pérez.
 * In the Justice League episode "A Better World, Part 1", an alternate Martian Manhunter lures the Justice League into a trap by deploying a similar story. The part that can be heard is, "...and the dimensions appear to be collapsing on each other..." and, "...perhaps by combining our forces, we may be able to avert this crisis which threatens all the infinite earths and all the divergent timestreams."
 * In the Justice League Unlimited episode "The Once and Future Thing, Part 2", Chronos' disruption of the timeline nearly results in history being erased with a "white field" effect similar to the anti-matter wave of the Crisis. A mastodon phases in front of the characters at one point. The Western era is visited. Batman and Green Lantern chase Chronos to the beginning of time, where they view a hand similar to the Anti-Monitor's holding the source spiral.
 * Another episode of Justice League Unlimited, "Far From Home", had Green Arrow, Supergirl, and Green Lantern shanghaied to the 31st century to aid the last free members of the Legion of Super Heroes. The Legion knows that Supergirl disappeared from history at this point, but does not say anything. Supergirl faces a brainwashed Legion — and Green Lantern, too, by that point — and is believed to be killed in the fight. Green Lantern holds her body in the same pose used by Superman on the cover of Crisis on Infinite Earths #7, surrounded by the Legion. She survives, but stays in the future, as it is more like her old home.
 * In the online web comic Gaming Guardians, an entire page is used as an homage to the death of Supergirl, right down to the infamous line, "But... We had a casualty."
 * The fourth and final issue of the Superman & Bugs Bunny mini-series was titled "Cwisis on Infinite Earths".
 * Issue #25 of the Animaniacs comic series showed a preview of fictitious stories supposedly planned for later issues. One of them was "Chaos on Infinite Watertowers!", described as "an epic retooling of the massive Warner universe", in which "worlds collide", "titans clash", and "Wakko gets a new hat."
 * In the Legion of Super-Heroes animated series, Brainiac 5 mentions a "Great Crisis" which resulted in many historical records being lost.
 * ToyFare #75 featured a Twisted ToyFare Theater story entitled "Crisis on Infinite Megovilles!" which involved Aunt May getting hold of the Infinity Gauntlet and using it to "clean up" alternate realities.
 * The Teenage Mutant Ninja Turtles movie, Turtles Forever, had a similar theme of infinite Earths filled with different variations of the Teenage Mutant Ninja Turtles and their enemies. They all originated from "Turtle-Prime", which is a parody of Earth Prime.
 * The Fox series, Fringe, a sci-fi show that involves alternate realities and parallel worlds, mentions a major event took place in the year 1985, the same year Crisis on Infinite Earths was first published. The show further featured "alternate" versions of DC Comics in the episode "Over There, Part 2", specifically an inversion of the famous cover of Superman carrying the body of Supergirl suggesting in Fringe's "alternate" universe that it was Superman who was killed as part of the crisis, while Supergirl survived.
 * Beginning with the October 2010 issue, Boom! Studios' Darkwing Duck comic book series begins a four-part story arc deemed "Crisis on Infinite Darkwings", apparently taking strong inspiration from this series.
 * In the Green Lantern: Emerald Knights movie, the Guardians noted that the Shadow Demons haven't been seen since "the great crisis".
 * The Batman: The Brave and the Bold episode "Night of the Batmen!" homages the cover to Crisis on Infinite Earths #7, with a sorrowful Aquaman holding the badly-injured body of Batman as Green Arrow, Plastic Man and Captain Marvel look on in shock.
 * The electro-rock band Judge Rock pays homage to Crisis in their 2012 song Westerner, in which Jonah Hex, Bat Lash, Nighthawk, Johnny Thunder and Scalphunter appear, along with the alien abduction taking them through time in episode three of the Crisis comic-book.
 * The series finale of Green Lantern: The Animated Series featured a storyline that involved a character going back in time to re-shape the creation of the universe. In this version, the villain was the sentient robot Aya, who had gained control of the Anti-Monitor's body and sought to erase emotion from the universe.