Crossovers of multiple characters owned by one company or published by one publisher, have been used to set an established continuity, where characters can frequently meet within one setting. This is especially true of comic book publishers, as different characters in various Marvel or DCcomic books frequently interact with one another.
Crossovers may also be advertised as a guest appearance or cameo appearance, often to promote another work of fiction, sometimes with little contextual or rational explanation.
A crossover story may try to explain its own reason for the crossover, such as "they live next door" or "a dimensional rift brought them together". Some crossovers are not explained at all. Some are absurd or simply impossible within the fictional setting, and have to be ignored by the series' respective continuities.
Most of these crossovers can be assumed to be in continuity for one or both of the characters or universes involved, although the events of the crossover may not be mentioned afterwards by either party. See fictional universe for more closely linked crossovers. Many spinoffs cross over with their parent series or originated as a one-time crossover.
Steve Urkel visits Full House and helps Mark in Step By Step. This actually does create a conflict. The episodes that Urkel was in clearly shows that these programs were originally in the same universe. Later in Step by Step, John Stamos appears as himself, even mentioning that he had a role on Full House.
Conan meets Elric (Conan the Barbarian, Marvel Comics)
Ace Ventura meets The Mask (The Mask and Ace Ventura animated series), playing off of the fact that Ace Ventura and the Mask were both played in their respective films by Jim Carrey.
Batman meets The Darkness (Batman/The Darkness) Note that Jackie Estracado frequently mentions this event, implying that the Top Cow universe has its own version of Batman and Gotham City, rather than the official DC Universe version.
Many daytime soap operas have had numerous crossovers over the years, particularly the ones that air on ABC. The baby switch storyline on ABC Daytime soap operas All My Children and One Life to Live, in which Paul Cramer (David Tom) from One Live to Live visited Pine Valley (the setting ofAll My Children) in order to steal the baby of his ex wife, Babe Chandler (Alexa Havins ) was part of an ongoing storyline with Babe later visiting Llanview (The setting of One Life to Live) in order to get her baby back from Paul. This storyline came to a climactic court battle which started one day on AMC and was continued the same day on OLTL . This particular storyline had a precendent in the fact that another All My Children character, Skye Chandler (Robin Christopher) had moved from Pine Valley to Llanview in order to find her birth mother. Skye later moved again to Port Charles, the setting for another ABC Daytime Soap Opera, General Hospital in order to find her biological father. When All My Children debuted in 1970 ABC had Michael Storm's Dr. Larry Wolek from One Life to Live apear on All My Children for a few episodes in an attempt for fans of OLTL to tune into their new soap opera. When Procter & Gamble cancelled Another World in 1999 several characters apeared on As The World Turns in an attempt to lure viewers to that soap.
These are crossovers that exist of their own setting, as an alternate universe or a "what if" scenario. Non-continuity crossovers may still borrow or resolve plots from their respective series, but have no evidence to support their occurrence officially in either setting.
Multiple Nintendo and third party video game characters exist in N-World, including Mega Man, Simon Belmont, Kid Icarus, Eggplant Wizard, Mother Brain, King Hippo, and Link (Captain N: The Game Master).
Multiple Capcom and Namco characters are brought together due to a dimensional rift (Namco x Capcom ).
Dream sequence
A character comes into contact with another character through imagery, dreams, visions, etc. The crossover itself does not occur, but the idea of the crossover might occur.
A real life celebrity or figure appears within a fictional setting (Does not have to be portrayed by the actual person).
In the Batmanlive actiontelevision series, celebrities often appeared when the Dynamic Duo are scaling a wall and the celebrity in question opens a window for a short conversation.
Huckleberry Hound devolves into a normal dog on The Brak Show (The Brak Show)
Amitabh Bachchan's character in the Bollywood film Maard briefly appears in the comic guise of Father Anthony, a persona that a different character played by Amitabh Bachchan, Anthony Gonsalves, had previously adopted in the film, Amar, Akbar, Anthony . In both films, the Father Anthony persona has the same costume, mannerisms and accent, even though Amitabh Bachchan is playing a different character in each of the two films.
A vast amount of fan fiction and fan art feature characters from multiple stories or settings crossing over with one another. Almost any two given popular universes, characters or stories can be assumed to have crossed over in some fan-made fiction, even when the basic idea of such a crossover would seem to run contrary to the style or themes of the source material.
