While watching the movie, in one scene when all of the guardians were trying to guess who is the new guardian the Man In The Moon had selected, Sandy thought the new guardian was the leprechaun, which made me think. What if there were other mythical beings who had the potential to be a guardian and what would their center be?
So the Leprechaun had the potential to be a guardian, but what will his center be?
I believe there are other potential guardians, and the other mythical beings don't have to be from the Rise of the Guardians book series or the film. The other mythical beings can also be from other fables, legends and stories