The rules of canon I’m operating by for this are pretty simple. The following are all considered canon. Should two sources conflict, then the higher ranked one takes precedent.
- Aired episodes & movies.
- With Supernatural, the original Kripke 5 seasons take precedent over the following seasons & spinoffs
- Extra items such as books & comics.
- The RPG books have higher priority over others.
- The Serenity comics are next.
- SPN comics & books are “canon if convenient & possible”.
- Creator interviews and scripts.
- Awesome fan makes (especially the “season that might have been” and serenity mush).