When Contagion Engine enters the battlefield, put a -1/-1 counter on each creature target player controls. {4}, {T}: Proliferate, then proliferate again. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)
NM-Mint - $12.10
Lightly Played - $10.90
Moderately Played - $9.70
Heavily Played - $8.50
Damaged - $6.10
NM-Mint Non English - $12.10
Lightly Played Non English - $10.90
Moderately Played Non English - $9.70
Heavily Played Non English - $8.50
Damaged Non English - $6.10
Foil Prices
NM-Mint Foil - $17.60
Lightly Played Foil - $15.90
Moderately Played Foil - $14.10
Heavily Played Foil - $12.40
Damaged Foil - $8.80
NM-Mint Foil Non English - $17.60
Lightly Played Foil Non English - $15.90
Moderately Played Foil Non English - $14.10
Heavily Played Foil Non English - $12.40
Damaged Foil Non English - $8.80