Screaming Swarm is a uncommon Creature — Bird Horror card from Innistrad: Crimson Vow (VOW), collector number 75. Current market price: $0.24 (foil $0.37), TCGplayer market prices via Scryfall.
Flying Whenever you attack with one or more creatures, target player mills that many cards. (To mill a card, a player puts the top card of their library into their graveyard.) {2}{U}: Put this card from your graveyard into your library second from the top.