Spells you cast have affinity for artifact creatures that weren't originally artifact creatures. (They cost 1 less to cast for each artifact creature you control that wasn't originally an artifact creature.)
1UU: Target permanent becomes an artifact in addition to its other types.
Near Mint - $20.90
Lightly Played - $18.80
Played - $14.70
Heavily Played - $12.60
Damaged - $10.50
Near Mint Non-English - $20.90
Lightly Played Non-English - $18.80
Played Non-English - $14.70
Heavily Played Non-English - $12.60
Damaged Non-English - $10.50