When Phyrexian Devourer's power is 7 or greater, sacrifice it. Exile the top card of your library: Put X +1/+1 counters on Phyrexian Devourer, where X is the exiled card's mana value.
NM-Mint - $42.00
Lightly Played - $39.90
Moderately Played - $37.80
Heavily Played - $33.60
Damaged - $27.30
NM-Mint Non English - $42.00
Lightly Played Non English - $39.90
Moderately Played Non English - $37.80
Heavily Played Non English - $33.60
Damaged Non English - $27.30