RuneQuest/YMMV

Adaptation Displacement: Anyone ever hear of White Bear and Red Moon? It was a tabletop wargame from 1975, and it was the game where the world of Glorantha was first introduced. Now, both the RPG and the video game are far better known.
Alternative Character Interpretation: All over the place. Take the Red Moon for example: is she an evil Chaos goddess who threatens the very existence of Glorantha? A messianic figure who aims to fix a broken world? Neither? Both? All interpretations are valid.
Base Breaker: The ducks. Either they're a marvelous example of how non-bogstandard the setting is, or they're a distractingly silly blot that spoils the mood.
Magnificent Bastard: Rashoran/a, if you believe s/he deliberately orchestrated several of the most important events in the history of Glorantha. Consider the facts: the Unholy Trio who brought the Devil into the world did so after being taught by Rashoran to not be afraid of Chaos. He was killed by them, but he returned; Nysalor was his incarnation. And, though Rashorana is now but one of Sedenya's facets, she is seemingly the one who inspired the Red Moon into trying to unite the world into the All, thus starting her Assimilation Plot.