Elspeth's Devotee is a rare Creature — Human Soldier card from Theros Beyond Death (THB), collector number 272. Current market price: $0.27, TCGplayer market prices via Scryfall.
When this creature enters, you may search your library and/or graveyard for a card named Elspeth, Undaunted Hero, reveal it, and put it into your hand. If you search your library this way, shuffle.