Kozilek's Unsealing is a uncommon Enchantment card from Modern Horizons 3 (MH3), collector number 65. Current market price: $0.30 (foil $0.40), TCGplayer market prices via Scryfall.
Devoid (This card has no color.) Whenever you cast a creature spell with mana value 4, 5, or 6, create two 0/1 colorless Eldrazi Spawn creature tokens with "Sacrifice this token: Add {C}." Whenever you cast a creature spell with mana value 7 or greater, draw three cards.