Nausicaa of the Valley of the Wind and Athanor
Once in an early conception of Athanor, I had used a lot of the ideas from Hayao Miyazaki's Nausicaa of the Valley of the WInd in thinking about Athanor. Over time, I had cut most of that away and forgotten about it. Generally, I don't use manga as an inspiration for much of anything, in particular RPGs, but I think Miyazaki in general (and Nausicaa in particular) is particularly worth mining for ideas.
I just realized that the use of fungus forests and ancient wars that devestate a planet still come from those early ideas. So add the Nausicaa manga as a recommended reading. Yes, even if you hate Manga and anime. It's well-written swashbuckling with some interesting ideosyncratic Miyazaki twists. I'm not anywhere near as fond of the anime, even less so of the English dub "Warriors of the WInd," but it's passible if inferior work (done when Miyazaki had just started working on the manga).
The themes of the dangers of technology, the response of nature to imbalance, and the dangers of human ambitions can all be found in Athanor as I hope for it to unfold. We'll have to see what (if anything) actually comes out in play.