Gran-Gran is a uncommon Legendary Creature — Human Peasant Ally card from Avatar: The Last Airbender (TLA), collector number 54. Current market price: $0.31 (foil $0.32), TCGplayer market prices via Scryfall.
Whenever Gran-Gran becomes tapped, draw a card, then discard a card. Noncreature spells you cast cost {1} less to cast as long as there are three or more Lesson cards in your graveyard.