Rotten Reunion is a common Instant card from Innistrad: Midnight Hunt (MID), collector number 119. Current market price: $0.25 (foil $0.41), TCGplayer market prices via Scryfall.
Exile up to one target card from a graveyard. Create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.) Flashback {1}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)