Nonartifact spells you cast have improvise. (Your artifacts can help cast those spells. Each artifact you tap after you're done activating mana abilities pays for {1}.)
"In the early days, Urza's wondrous automatons were seen as symbols of hope and courage."
—*The Antiquities War*
NM-Mint Foil - $397.00
Lightly Played Foil - $377.20
Moderately Played Foil - $357.30
Heavily Played Foil - $317.60
Damaged Foil - $258.10
NM-Mint Foil Non English - $397.00
Lightly Played Foil Non English - $377.20
Moderately Played Foil Non English - $357.30
Heavily Played Foil Non English - $317.60
Damaged Foil Non English - $258.10