Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.) At the beginning of your upkeep, put a rust counter on each artifact target opponent controls. Then destroy each artifact with converted mana cost less than or equal to the number of rust counters on it. Artifacts destroyed this way can't be regenerated. When Corrosion leaves the battlefield, remove all rust counters from all permanents.
Near Mint - $600
Lightly Played - $500
Moderately Played - $400
Heavily Played - $400
Damaged - $300
Near Mint Spanish - $600
Lightly Played Spanish - $500
Moderately Played Spanish - $400
Heavily Played Spanish - $400
Damaged Spanish - $300