Creature and planeswalker spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.) +2: Tezzeret, Master of the Bridge deals X damage to each opponent, where X is the number of artifacts you control. You gain X life. −3: Return target artifact card from your graveyard to your hand. −8: Exile the top ten cards of your library. Put all artifact cards from among them onto the battlefield.