Speaking of having a number of kooky, incompatible, differently-implemented magic systems... doesn't the Palladium Fantasy game have this in spades?
In ERB's Mars series John Carter becomes telepathic in the first book. I think it's from contact with a machine but I can't recall.
That's what I assumed, but is it ever explicitly stated? I've only read the first three Barsoom books.No, it's because John has been a martian all along. Hense, his long life, natural telepathic ability, and ability to interbreed with the egg laying martians.
Not that I've ever seen, no.That's what I assumed, but is it every explicitly stated? I've read the first three Barsoom books.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.