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 - $15.30
Lightly Played - $13.80
Moderately Played - $12.20
Heavily Played - $10.70
Damaged - $7.70
NM-Mint Non English - $15.30
Lightly Played Non English - $13.80
Moderately Played Non English - $12.20
Heavily Played Non English - $10.70
Damaged Non English - $7.70
Foil Prices
NM-Mint Foil - $23.80
Lightly Played Foil - $21.40
Moderately Played Foil - $19.00
Heavily Played Foil - $16.60
Damaged Foil - $11.90
NM-Mint Foil Non English - $23.80
Lightly Played Foil Non English - $21.40
Moderately Played Foil Non English - $19.00
Heavily Played Foil Non English - $16.60
Damaged Foil Non English - $11.90