If you mash up enough old stuff, you get something new.
I had a one off that used Eboshi and the lepers from Princess Mononoke, a nutty scientist who was basically Jack from the genetically engineered team on DS9, and the big boss was the Shrike from Hyperion. Plus a bit where a kid found a big pod in the forest, got really excited, brought it back to the village, and rolled it down a hill against another kid's pod while shouting "Now this is pod racing!"
One player gave me two middle fingers for that. I regret nothing.
Point is making all those fit together into a coherent story isn't a simple task. It's also basically how Tarantino makes his movies.