A hyperflexible mythology is a narrative device for the exposition of characters, settings, and powersets. It introduces a system of archetypes within a story that divides a foundational aspect of that story into categories, or "houses". If the audience understands the symbolism the author attaches to a house, they will intuit the behaviour of someone or something belonging to that house more efficiently than would be intuited by conventional exposition for each character. When an author introduces a character or concept who belongs to a house for which there has already been exposition, the audience will have a better idea of what to expect from the character or concept being introduced, allowing the author to decide how they want to use those expectations.
The term “hyperflexible mythology” was coined on the 2nd of March, 2010, by Andrew Hussie, in his webcomic “Homestuck”. It was used in-universe by the character Terezi Pyrope, in a conversation between her and Rose Lalonde, about the nature of their setting, and the destinies it expects them to follow.
“GC: TH4T H3LP3D US R34LIZ3 TH3 P4RTICUL4R D3ST1N13S THE G4M3 PUT TOG3TH3R FOR US
GC: 1N TH3 VOC4BUL4RY OF L1K3
GC: TH3 HYP3R FL3XIBL3 MYTHOLOGY 1T T41LORS TO 34CH PL4Y3R GROUP” – Terezi Pyrope (Hussie, 2010. p. 1524, l. 76–78)
It is beneficial to the success of a hyperflexible mythology that each house has an easily-recognisable symbol, its own associated traits, actions and philosophies, and, if the story uses a visual medium, its own associated colour or style of clothing. This avoids confusion when many characters from different houses are in the same scene, making it easier for the audience to absorb the amount of information being presented.
Hyperflexible mythology can be compared to the act of "colour-coding" a character design, based on what personality and powerset the audience expects a character with a certain colour scheme to have. Where hyperflexible mythology differs is in attaching a given colour scheme with a given personality type and powerset, within the specific context of the work itself.
In some works, the houses (including their associated characters) interact with other houses in the work - and with themselves - in complex ways. A work might allow for "super-houses" (where a new house is created by taking some or all of the traits of two or more base houses), or for "sub-houses" (where a single house has some of its traits diverge from each other, either by a character's actions, or by the parallel development of cultures). A work might allow for "trans-house development", where a character changes their associated house during the story, or for "extra-house development", where a character stops associating themselves with the hyperflexible mythology of the work.
In fandom spaces, the names of houses are employed as shorthand for the personality of the user of the house name. The use of a house name signals to others in the space that the user is a fan of the work from which the house name originates, and believes the house name they are using to describe either the personality and philosophy they have, or the personality and philosophy they wish to have. This can be compared to the (pop-culture) use of the Zodiacs, MBTI Personalities, Enneagrams, Blood Type Personalities, etc. If another person in the same fandom space is aware of the meaning of each of the house names someone is using to describe themselves, they will have a better idea of what to expect from an interaction with the user of those house names.
In these fandom spaces, fans who are familiar with the hyperflexible mythology of two or more works might, in crossover works between those two or more works, assign a character from one work to a house from the hyperflexible mythology of another work. Such fans might also take a character from a work without a hyperflexible mythology, and assign that character to a house in one of the hyperflexible mythologies they know.
Some works known for their hyperflexible mythologies include:
Final Fantasy (the Job System, introduced in 1987);
Magic: the Gathering (the Mana Wheel or Color Pie, introduced in 1993);
Pokémon (the Type Chart, introduced in 1996);
A Song of Ice and Fire (the Noble Houses, introduced in 1996);
Harry Potter (the Hogwarts Houses, introduced in 1997);
Avatar: The Last Airbender (the Elements, introduced in 2005);
Homestuck (the Classes, Aspects, and Dream Moons, introduced in 2009; the Hemospectrum, introduced in 2010);
Divergent (the Factions, introduced in 2011);
Steven Universe (the Gems, introduced in 2013).