Moan of the Unhallowed is a uncommon Sorcery card from Foundations Jumpstart (J25), collector number 461. Current market price: $0.30, TCGplayer market prices via Scryfall.
Create two 2/2 black Zombie creature tokens. Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)