Table of Contents
A character may only be eligible for a crossover if they fulfill the following prerequisites:
- The character is inherently fictitious.
- The character is copyrighted at the time of the crossover.
- The copyrighted version of the character personally appears in the crossover.
A prospective crossover's eligibility for addition to the roadmap is based solely on its lore legitimacy and not the copyright holder's perception of that crossover's canonicity within the confines of the chracters' home universe. It is important to note that even if a copyright holder specifically states that a crossover is not considered canon within their universe, the crossover could still be — and usually is — considered canon within the universe that their characters cross into. Furthermore, most crossovers do not possess any remarks from the copyright holders at all regarding their canonicity. Thus, the only fair way to judge a crossover's eligibility is by way of its lore.
A crossover's lore is the story — or reason — for its existence. Specifically, the subject of crossover lore concerns how two or more unrelated characters are able to interact with one another. Commonly, the lore is simply that their universes coexist and the two characters have lived down the street from one another all along. Sometimes, inter-dimensional travel and portals to other dimensions are required. In any case, the legitimacy of the lore lends credence to a crossover's eligibility. Crossover Magnitudes covers specific lore archetypes along with their respective eligibilities.
Crossovers are divided into the following magnitudes. It's worth noting that the examples provided for each magnitude type comprise a living list — meaning that it will grow as additional edge cases crop up.
Crossover magnitudes that constitute addition to the roadmap.
Type 1 (Alpha) - Bound universes. A crossover that portrays various universes as coexisting, implying that they are bound to one another.
Lore Archetypes
- A character from Universe B makes an appearance in Universe A and no fuss whatsoever is made about how they wound up there. An example of this lore archetype would be numerous episodes of the TV show The New Scooby-Doo Movies wherein characters from an abundance of other universes cross paths with Mystery Inc. to help them solve mysteries.
Type 2 (Beta) - Tangential universes. A crossover that portrays various universes as being linked by means of inter-dimensional travel, implying that they are tangential to one another.
Lore Archetypes
- A character from Universe B travels through a portal and appears in Universe A, thereby creating a tangible link between the two universes. An example of this lore archetype would be the one-shot comic book Star Trek/X-Men wherein the Marvel universe's X-Men enter the Star Trek universe through a rift of psionic energy in space.
Type 3 (Gamma) - Presumably bound universes. A crossover that — while only portraying a single universe — alludes to other universes as coexisting, implying — but never proving — that they are bound to one another. *
Lore Archetypes
- A character from Universe B refers to a character from Universe A as though they are personally acquainted despite the referenced character never actually making an appearance. An example of this lore archetype would be the episode of the TV show Family Matters wherein Steve Urkel refers to Cory Matthews from Boy Meets World as his good friend.
Crossover magnitudes that do not constitute addition to the roadmap.
Type 4 (Delta) - Tangential sub-universes. A crossover that portrays a single universe within which various sub-universes exist fictionally, implying that the sub-universes aren't rooted in any reality and are in no way linked to the portrayed universe.
Lore Archetypes
- A character from Universe B refers to a character from Universe A as though the character is fictitious and couldn’t possibly be present at any time. An example of this lore archetype would be the numerous references on the TV show Seinfeld that are made to Superman as a fictional character in comic books and animated television shows.
- A character from Universe B dreams, imagines, or otherwise conjures up the idea of interacting with a character from Universe A, but their interactions are isolated to imagination alone and never take place in reality. An example of this lore archetype would be the book Ready Player One wherein hundreds of copyrighted characters make an appearance, but all of these appearances are made within the context of a video game that is merely alluding to them as fictional characters within pop culture.
