Witty Demon is a rare Creature — Demon card from Mystery Booster Playtest Cards 2019 (CMB1), collector number 50. Current market price: $0.98, TCGplayer market prices via Scryfall.
Flying When Witty Demon enters, if your starting library had at least 13 cards over the minimum, search your library for a card and put that card into your hand, then shuffle your library. Otherwise, Witty Demon deals 4 damage to you.