Many animes use the idea of "mana", an energy source for magic that if it's consumed deny magic users the possibility of casting more spells. Some animes which uses this are A Certain Magical Index (2008) (and spin offs such as A Certain Scientific Accelerator (2019) and A Certain Scientific Railgun (2009)) , Arifureta shokugyou de sekai saikyou (2019), Black Clover (2017), etc , but the first use in a fiction AFAIK was in a 1969 american novel. Then at some point after that and very likely before the animes I mentioned, mana was first used in an anime. But when was this? Which was the first anime to feature mana as energy source for magic?