Plans storylines far in advance for all his television series, allowing for remarkable long-term continuity.
Frequent use of nouns as adjectives, by adding the suffix "-y"
Features tough, strong female characters
Kills off characters who are among his most popular, to keep his audiences surprised.
Supernatural and science fiction themes
Often gives his characters names that are later revealed to be their last names and/or based on an unusual abbreviation for their full name. For example: only after the character Oz had already left Buffy the Vampire Slayer (1997) did the show reveal that "Oz" was an abbreviation of his full name, Daniel Osbourne; on "Angel," they did not clarify that Doyle was actually the character's last name for many episodes; "Xander," the name of a main Buffy character, is a much less usual nickname for "Alexander" than the much more common "Alex;" and likewise for the name "Topher," the name of a main Dollhouse (2009) character, which is a much less usual nickname for "Christopher" than the much more common "Chris.". Whedon's own nickname, "Joss," is an uncommon diminuitive of "Joseph," which is much more often abbreviated "Joe."
Frequently casts Nathan Fillion and Alan Tudyk
References to classic stories and films, through storytelling methods and direct reference in dialogue
Tongue-in-cheek, witty writing style
Frequently includes ballet/ballerinas in his projects - though almost always with a supernatuural twist to their inclusion (Angel, Cabin in the Woods, Avengers: Age of Ultron, etc.)