Call to the Grave is a rare Enchantment card from Scourge (SCG), collector number 58. Current market price: $1.15 (foil $15.05), TCGplayer market prices via Scryfall.
At the beginning of each player's upkeep, that player sacrifices a non-Zombie creature of their choice. At the beginning of the end step, if no creatures are on the battlefield, sacrifice this enchantment.