I mean, without delving into spoilers, the idea of a world and a society that undergoes major structural cycles is a GRRM idea as much as it is a Miyazaki idea.

I mean, without delving into spoilers, the idea of a world and a society that undergoes major structural cycles is a GRRM idea as much as it is a Miyazaki idea. I'm sure he had some kind of impact on the story, they are just already very aligned on the big ideas going into it. Besides that, most if not all of the major bosses/characters names start with either a G, R, or M.