While Larry Niven is most famous for his hard science fiction, in the traditional sense of the term, he also has a fantasy universe, with a decent introduction at https://en.wikipedia.org/wiki/The_Magic_Goes_Away In this universe, magic is a finite quantity, which gets used up. The modern world is mundane not because magic is impossible, but because it was all used up.

(It would be interesting if he ever wrote the story set in this universe, after the modern times, in which humanity gets out to space, and, uh, hey guyz, magic kinda... works out here... what the heck? It wouldn't necessarily take long to figure out what the deal is with Earth being a dead zone, but it would cause some interesting political upheaval as suddenly the sparse space colonies that nobody thought were worth anything and barely even worth the effort became industrial powerhouses as the only place where magic works... and not just the tame, dying magic of Niven's stories, but the original wild, abundant magic the stories claimed Earth initially had.)

Nevinyrral's Disk, at a minimum.

https://gatherer.wizards.com/Pages/Card/Details.aspx?multive...

The entire concept of mana being generated from land.