quote

Fantasy writer Larry Niven in his 1978 novella, The Magic Goes Away, describes "mana" as a natural resource which is used or channeled by wizards to cast magic spells. Mana is a limited resource in Niven's work, a fact which eventually will lead to the end of all magic in his antediluvian fantasy setting when all mana is depleted.

Many subsequent fantasy settings (role-playing games in particular) have followed Niven in his use of mana. In the manga version of Archie Comics' Sabrina the Teenage Witch, for example, the Mana Tree is the source of all mystical energy in the Magic Realm. Some of the first computer games to adopt mana as a term for magic points were the role-playing game Dungeon Master (1987), and the god game Populous (1989), where mana is the resource used by gods (such as the player) to make divine interventions. The regeneration rate of mana in this setting is proportional to the god's number of followers. Other later games to include mana as a source of magical power are Secret of Mana, EverQuest, Warcraft, LostMagic, and Diablo as well as their sequels. Mana is also a key resource in the card game Magic: The Gathering.