Lo and Li, Twin Tutors is a uncommon Legendary Creature — Human Advisor card from Avatar: The Last Airbender (TLA), collector number 108. Current market price: $0.16 (foil $0.24), TCGplayer market prices via Scryfall.
When Lo and Li enter, search your library for a Lesson or Noble card, reveal it, put it into your hand, then shuffle. Noble creatures you control and Lesson spells you control have lifelink.