Wretched Throng is a common Creature — Zombie Horror card from Innistrad: Crimson Vow (VOW), collector number 91. Current market price: $0.11 (foil $0.05), TCGplayer market prices via Scryfall.
When this creature dies, you may search your library for a card named Wretched Throng, reveal it, put it into your hand, then shuffle.