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 Foil - $56.30
Lightly Played Foil - $53.50
Moderately Played Foil - $50.70
Heavily Played Foil - $45.10
Damaged Foil - $36.60
NM-Mint Foil Non English - $56.30
Lightly Played Foil Non English - $53.50
Moderately Played Foil Non English - $50.70
Heavily Played Foil Non English - $45.10
Damaged Foil Non English - $36.60