There are some crossovers that are blindingly obvious, but can never quite get off the ground. Maybe one of the creators didn't like the idea, maybe the characters are owned by different companies that can't make a deal, maybe it just got stuck in Development Hell somewhere along the way. Regardless, one side of the crossover still wants to do it enough that they're willing to bend the rules a little bit to make it happen. After all, what does it matter if it's not Superman that's punching Captain America in the face for the vaguest of reasons, but Duperman?
A Spiritual Crossover is what happens when a Fake Crossover meets Spiritual Adaptation. The characters created as a result may vanish after fulfilling their crossover purpose, or they may stick around, since they're owned by the same company and there are thus no restrictions to their use.
This may involve a Cast of Expies, in case there are several individual characters copied from a different work or works instead of just one. Also, do not be surprised if these newly-made characters are made a little more villainous than their original versions just to pour some more salt on the wound.
Compare/Contrast Captain Ersatz and Expy, which are about individual clones of another company/writer's character that aren't necessarily involved in any sort of Crossover plot. Do not confuse with the aforementioned Fake Crossover, which is actually about genuine crossovers that don't count in the chronology of one or both franchises involved.
- The Champions of Angor, a team of Ersatzes of The Avengers, battled the Justice League the exact same month that the Squadron Supreme (a team of Justice League copycats) fought the Avengers in their book. This was done because the writers on both books were friends. So if you bought a copy of Justice League in February of 1971, you got to see them Let's You and Him Fight with the Avengers, but not really, and fans of the Avengers had the opposite experience.
- Another simultaneous example from Marvel and DC were the Crusaders. In the late seventies, DC's Freedom Fighters battled a team by that name based on Marvel's Invaders, whilst the Invaders faced off with another team with the same name in their book, but based on the Freedom Fighters. More information can be found in their respective wiki pages.
- Though it's already a Massively Multiplayer Crossover of several public domain characters and novels, The League of Extraordinary Gentlemen ran into this when Alan Moore tried to add more contemporary characters. Jimmy Bond, an incompetent and mysogynistic agent of the British Secret Service, was introduced in The Black Dossier as an antagonist, and Volume 3: Century had The Antichrist, an orphan with magical powers who studied at a secret school for wizards go on a killing spree after discovering his destiny and killing many of his supporting cast (though they were all satanists here, so who cares) Needless to say, many people were pissed off at these.
- The Multiversity has characters from the DCU deal with not only characters from Major Comics, but also the likes of Spore and Dino-Cop. The concept of the series is that all the comics in our world are doors to parallel universes, so it seems Grant Morrison felt they had to be in there one way or another to complete the Kayfabe.
- Not Brand Echh had an entire issue dedicated to this, though this being Brand Echh, both sides were comprised of Captain Ersatzes: Spidey-Man battled Gnatman And Rotten, The Ironed Man dueled with Magnut, Robot Biter and Knock Furious, agent of S.H.E.E.S.H. fought the Blunder Agents. And it was glorious.
- A strange issue of Power Man and Iron Fist had the pair interacting with a very blatant expy of Doctor Who named Professor Gamble, a former member of the Time Variance Authority who used a time machine able to camouflage itself according to its surroundings (it usually takes a form less conspicuous than a phone booth, though). Luke and Danny end up having to defend an actor playing Gamble in a broadway production from the "Dredloks" (the Daleks, but saying "Incinerate!" instead of 'Exterminate!"). It should be noted Marvel did have the rights for the Doctor at the time, so this instance was most likely done so they didn't have to worry about not being able to reprint the story later. Gamble remained a (minor) part of the Marvel universe thereafter. Oh, and that Broadway play? It was called "Day of the Dredloks".
- There was the incident in the Quasar comics where several characters with Super Speed competed on a race to the moon, organized by the Runner, one of the Elders of the Universe. One such character was "Buried Alien", a speedster who suddenly appeared on the track in a flash of lightning, amnesiac but with the feeling he was no longer in his own universe. It's heavily implied that this is Barry Allen, having been thrown into the Marvel universe after his seeming sacrifice in the Crisis on Infinite Earths. However, enough details are different that it's clear he isn't Barry - he has a beard and taps into something called "Hyperspeed", not the Speed Force, for instance. Regardless, fellow speedster Makkari brought him back to wherever he originally came from, and Buried Alien hasn't returned to Earth-616 since.
Runner: Well, Buried, how does it feel to be the fastest man alive?
Buried: It feels... right.
- A very mean-spirited version happened over at the pages of Savage Dragon with Johnny Redbeard's 'Nixed Men'. Every single one of them was based on a Marvel or DC character that John Byrne had reinvented in the past, and as such were all Ersatzes: Sensation (She-Hulk), Fade (the Invisible Woman), Sub-Human (Submariner), Super-X (Superman) and Lightning Bug (Storm). Of these, the only one who survived was Sensation, who managed to become Savage Dragon's Distaff Counterpart, She-Dragon. The name of the team may seem like a reference to the X-Men, but it is in fact a dig at a team Byrne created for Dark Horse... the Next Men.
- Speaking of She-Hulk, she teamed up with a Gender Bender-fied Batman (in his first movie form) expy called "Nosferata the She-Bat" in issues #19 and #20 of her second ongoing, in a story titled "Year Zero". In fact, the entire city of Gotham was expied as the city of Visigoth, down to Hamilton Hill becoming Hieronymous Hill.
- Shown above is the Squadron Sinister, the first incarnation of the Squadron Supreme, who debuted in The Avengers as analogues of the Justice League. Their heroic counterparts would appear later and were even better examples of this trope: A superhero team from another dimension brainwashed into fighting the Avengers by a supervillain (again and again). It really sounds like a lazy script for a crossover that never got made. Then it did get made, and this is what Hawkeye had to say about the Justice League:
Hawkeye: Oh, right - now I got it! These losers are nothing more than a bunch of Squadron Supreme wannabes! Five gets you ten they're mind-controlled.
- Superman #276 starts with a young kid named Willie (as opposed to Billy) Fawcett being transported 20 years into the future and meeting Superman. Willie is secretly Captain Thunder, a superhero from a bygone era, who gained his powers from a wizard who lived in a cave. Upon rubbing his magical belt buckle and saying "Thundernote !", he is transformed into his alter ego with a "Sha-Boom!" sound to fight evildoers! However, the Monster League of Evil somehow made Thunder turn heel and help criminals instead of stopping them (to facilitate Let's You and Him Fight with Superman, naturally). Criminals call him a "cheap imitation" of Superman, and Supes refers to him as "Big Red" at one point. Superman defeats him by tricking him into saying "Thunder" again and changing back. In case you still haven't figured it out, Captain Thunder is Shazam!; the whole story was created to see if readers would be interested in reading about the real thing, as DC had just acquired the character. Seriously, just look at him!
- Superman/Batman #20-25 had the titular heroes being transported to the world of The Maximums, who wanted revenge after a brainwashed Superman/Batman killed one of their teammates, Skyscraper (Giant-Man). It was ultimately revealed that the plot was masterminded by The Joker and Mr. Mxyzptlk, playing a cosmic game in exchange for gaining - or losing - their Reality Warper powers. This was, itself, a reference to similar plotlines involving the Squadron Supreme. The story culminated in many Supermen and Batmen being combined into the Composite Superman-Batman and the Maximums being combined into The Maximum Maximum, and then they fought. It's that kind of series.
Maximum Maximum: Do your best, you Dirty Cowardnote . This day will be won by the one true Ultimate warrior!
- At one point Marvel and DC had a special type of crossover in mind: one character of each company would be stranded, for a year, in the universe of the other company, that would use it for a year as they saw fit. The project fell into Development Hell and was never done. So Marvel did it on their own: at the turn of the century they had the Ultimate Marvel universe (an Ultimate Universe of the Marvel universe) and the Supreme Power universe (an Ultimate Universe of the aforementioned Squadron Supreme, and so based on DC Comics to some degree). There was a crossover between both in "Ultimate Power", and after it Nick Fury was moved to the Supreme Power universe and Zarda to the Ultimate Marvel one.
- Vampirella vs Fluffy has Vampirella teaming up with a blatant Expy of Buffy the Vampire Slayer. Fluffy even had her own stand ins for Buffy's supporting cast: Xtanley (Xander), Sallow (Willow), Carmilla (Cordelia) and Miles (Giles).
- Godzilla vs. Mechagodzilla: Godzilla teams up with King Caesar, the monstrous, but peaceful, guardian of a secluded island, whose natives can control with an ancient chant. Replace the word 'Caesar' with 'Kong' and that same description could apply to the Toho version of King Kong seen in King Kong vs. Godzilla, released a decade earlier, down to even having the same roar (not even modified or anything). The homage is sent up in Godzilla vs. Kong, where Kong and Godzilla join forces to defeat Mechagodzilla, the same kaiju that Godzilla and Caesar defeated in that movie.
- Godzilla vs. Megalon: Paying the folks at Ultraman back for Jirahs (listed in Live-Action TV below), this movie introduced 'Jet Jaguar' to the Godzilla franchise, who was the heroic focus of the movie. Said character looks nearly identical to Ultraman and can change size just like him. The movie ends with a So Bad, It's Good Theme Song for Jaguar that sounds like it would be played in the opening for a Tokusatsu show. Interestingly, not only was his original design much less of a blatant copy (looking vaguely like a Mazinger Z with a Ultraman-inspired color scheme), but he was originally meant to be the de facto star of the movie, and Godzilla was only included to boost sales. Which was probably a good idea, since Jet Jaguar is much more famous now as "That guy they used to make it look like Godzilla was fighting Ultraman" than he would have been as "That blatant Ultraman ripoff Toho tried to steal our money with".
- Friday the 13th Part VII: The New Blood could have easily been retitled "Jason vs. Carrie", as Jason has to fight a young girl with telekinetic powers suspiciously similar to Carrie White.
- The creator of Arsène Lupin really wanted his Gentleman Thief to match wits with the greatest detective character of the time, Sherlock Holmes. But Arthur Conan Doyle objected, so instead Leblanc just went and swapped the initials. The UK version at least tried to soften the blow by renaming him to 'Holmlock Shears'. The story would be adapted into a german film serial, whose copyright laws allowed it to become a genuine crossover. And of course, after both authors were dead, the two characters would tangle many a time in the hands of other writersnote .
- The Canary Trainer, essentially a published Sherlock Holmes AU fanfic, saw the world's greatest detective embroiled in the world of theatre and opera, and meeting up with the Opera Ghost who haunted that particular opera house.
- The Doctor Who Expanded Universe loves this trope:
- The Past Doctor Adventures story The Indestructible Man focused on Dystopian versions of Gerry Anderson's creations. In particular, the title character himself is obviously Captain Scarlet. The summary for the book outright calls him "a man destiny has made indestructible", and his name, Grant Matthews, tuckerizes both the model for his appearance, Cary Grant, and his voice actor, Francis Matthews.
- The Doctor Who Missing Adventures novel Burning Heart is an interesting example, making the Doctor interact with Expies of Judge Dredd (Adjudicator Craator) who defends Habitat (Mega-City One). What makes it interesting is not the subject of the crossover, but rather that the publisher HAD the rights for the Judge Dredd character, but decided against an official crossover, thus enforcing this.
- The Eighth Doctor Adventures story The Crooked World had the Doctor land in an Alternate Tooniverse filled with Warner Bros. properties, such as The Skeleton Crew, a group of five mystery-solving teens (and their dog), as well as Jasper and Squeak.
- A Study in Emerald by Neil Gaiman centers around an unnamed war veteran who teams up with a just-as-unnamed brilliant, yet misanthropic genius to combat a revolutionary and his partner who are trying to destabilize the peace brought by The Old Ones to earth. The revolutionary's name? Why, Sherlock Holmes. The narrator, who we were led to believe was Watson, is in fact Sebastian Moran, Dragon of Moriarty. The Twist Ending thus changes the story from this trope into an actual crossover of the two properties.
- Community: The episode "Regional Holiday Music" is an extended Take That! to Glee. The episode has the study group facing off with a very blatant Expy of Mr. Schue, who tries to get them to join his glee club after the previous members had died. It's also revealed he's responsible for that glee club's death.
- The tokusatsu show Go Greenman had the episode Greenman vs Gorilla, the latter of whom is simply a reused King Kong suit from King Kong vs. Godzilla. The character itself is a generic monster of the day in pretty much all respects, but it would have been the real deal had Toho not lost the rights to Kong.
- Ultraman had the titular character battle Jirahs, expy of Godzilla. Aside from the name itself sounding like a shortening of GoJIRA, it was played by the same actor in an outfit cobbled together from separate Godzilla suits (on loan from Toho themselves) and given a neck frill, and had a modified Godzilla roar. Then Ultraman rips the neck frill off. It should be noted that this was something of an example of Real Life Writes the Plot - Eiji Tsuburaya wanted to make a more original kaiju for episode 10, but budgetary constraints forced them to go with the lazy option. It worked - Jirahs is one of the most famous Ultraman monsters precisely because of its nature as a Godzilla expy.
- Batman: The Animated Series: The episode "Beware the Creeper" essentially uses the titular character as an expy of Freakazoid!, making the episode into a strange blend of this and an actual crossover (The Creeper is a preexisting DC Comics hero). The fact that the showrunners for Batman also worked on Freakazoid, as well as how the show was cancelled only a year before this episode aired, might have had something to do with it. Their names are even both synonyms for "weirdo"!
- Batman Beyond: "Heroes" centered around a new group of superheroes called "The Terrific Trio", ironically enough a name once used for Batman, Robin and Batgirl. They were scientists transformed by a Freak Lab Accident and are clear references to the Fantastic Four, but the personalities and roles have been flipped around somewhat. Further, General Norman is subbing in for General Ross, and the trio's ally Dr. Hodges is what Reed Richards would have been had the accusations Doctor Doom made about him been true: sabotaging an experiment by his close friend out of petty jealousy, leading to an accident that scars both their bodies and their minds. The Trio is eventually confronted by Batman, and let's just say it doesn't end well.
- Justice League Unlimited: The team of Doctor Fate, Aquaman, Solomon Grundy, Hawkgirl, Superman and Wonder Woman battled the octopoid abomination Icthultu in the episode "The Terror Beyond". Totally not Cthulhu, you see. Even though they literally call him an "old one" in the episode...note
- Teenage Mutant Ninja Turtles (2003): In the third season episode, "The Darkness Within", the Ninja Turtles go up against a tentacled demonic Eldritch Abomination known as "The Necromonster". In other words, it's basically the TMNT going up against Cthulhu.