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 converted mana cost.
Near Mint - $23,200
Lightly Played - $18,500
Moderately Played - $16,200
Heavily Played - $13,900
Damaged - $11,600
Near Mint Spanish - $23,200
Lightly Played Spanish - $18,500
Moderately Played Spanish - $16,200
Heavily Played Spanish - $13,900
Damaged Spanish - $11,600