Sifter of Skulls is a rare Creature — Eldrazi card from Oath of the Gatewatch (OGW), collector number 77. Current market price: $0.82 (foil $2.43), TCGplayer market prices via Scryfall.
Devoid (This card has no color.) Whenever another nontoken creature you control dies, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this token: Add {C}." ({C} represents colorless mana.)