Dutiful Knowledge Seeker is a uncommon Creature — Fox Spirit card from Avatar: The Last Airbender Eternal (TLE), collector number 92. Current market price: $0.20 (foil $0.88), TCGplayer market prices via Scryfall.
Whenever one or more cards are put into a library from anywhere, put a +1/+1 counter on this creature. {3}: Put target card from a graveyard on the bottom of its owner's library.