Thought Harvester is a uncommon Creature — Eldrazi Drone card from Oath of the Gatewatch (OGW), collector number 48. Current market price: $0.16 (foil $0.32), TCGplayer market prices via Scryfall.
Devoid (This card has no color.) Flying Whenever you cast a colorless spell, target opponent exiles the top card of their library.