The Buffyverse canon consists of materials that are thought to be genuine (or "official") and those events, characters, settings, etc., that are considered to have inarguable existence within the fictional universe established by the television series Buffy the Vampire Slayer.
The creator of the Buffyverse, Joss Whedon, has implied that additional materials he was not heavily involved in creating were separate from canon.
Jeff Mariotte, author of Buffyverse novels and comics has said: The rule in licensed fiction is that what's on the screen is canon, and the rest is not.
[6]In a separate interview, Whedon spoke of the planning process for the series: I basically said, "We could do something and for once we could make it canon.
Whedon: No, because if they stopped doing Battlestar Galactica, and then two or three years later Ron Moore and David Eick said, "We ourselves are going to continue the story in comic-book form—as opposed to something ancillary to the show done by other people," then I would be all over it.
Doug Petrie wrote comics Ring of Fire, Double Cross, and Bad Dog.
Jane Espenson has written comics (Haunted, Jonathan, and Reunion), as well as two Tales of the Slayer prose shorts ("Again, Sunnydale" and "Two Teenage Girls at the Mall").
Rebecca Rand Kirshner also wrote a prose short story for Tales of the Slayer, "The War Between the States".
All other Buffyverse comics and novels were written by authors that were not involved with any level of production of the television series Buffy the Vampire Slayer or Angel.
The creators of these works are generally free to tell their own stories set in the Buffyverse,[citation needed] and may or may not keep to established continuity.
Similarly, writers for the TV series were under no obligation to use continuity which has been established by the Expanded Universe,[citation needed] and sometimes contradicted it.
[13]Similarly, Peter David was asked about his comic, Spike: Old Times, and said: Ostensibly comments came from Whedon, although for all I know, it was from an associate.
[14]Jeff Mariotte has revealed more detail of the approval process: I come up with a proposal that's eight or ten pages long and I submit that to Pocket Books.
[15]Mariotte implies that little input is given, only acceptance or rejection of general ideas: In the world of licensing there is a difference between 'approval' and 'input', and I'm not sure what the legal relationship between Fox and Mutant Enemy is.
In one instance, Whedon has endorsed a comic neither written nor supervised by him, The Origin by Christopher Golden and Dan Brereton, as canonical.
When After the Fall became an ongoing series penned by various writers, the canonicity of later stories became somewhat nebulous without the explicit say-so of those involved or Whedon himself.
In 2001, Whedon described his experience watching the film: I finally sat down and had written it and somebody had made it into a movie, and I felt like – well, that's not quite her.
It features Angel speaking toward the camera (possibly breaking the Fourth wall) and narrating action seen in clips.
Mutant Enemy Productions have at various times gone into the early stages of development with potential Buffyverse spinoffs that were ultimately unproduced.
[21] The David Fury-written script "Corrupt" establishes an alternative continuity after the premiere Angel episode, "City of".