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.
