Land of Oz/YMMV

Ensemble Darkhorse: The Patchwork Girl was very popular when she debuted, but nowadays Jack Pumpkinhead has been gaining quite a bit of popularity.
Fanon: Since continuity and backstory are pretty vague at best, there have been many attempts by fans to make it more coherent. Sometimes an attempt is good enough to be considered good as canon by fans.
Fanon Discontinuity: After the first two books, it's pretty easy to just take your pick of whatever you don't want to consider canon. Baum didn't seem to worry too much about what was canon either.
Germans Love David Hasselhoff: The Oz books are more popular overseas than in America.
Nightmare Fuel: The Oz books have several instances of this, as does the movie Return to Oz. It's possible to make a complete list of this.
- How Princess Ozma was found in The Marvelous Land of Oz might qualify.
- Princess Ozma had Bungle's brains changed to make her more agreeable. (May count as Canon Discontinuity as Bungle has her old brains and attitude back in later books.)
The Woobie: Ojo the Unlucky.