Manifest the top card of your library, then put X +1/+1 counters on it. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)
Near Mint - $1.40
Near Mint Non-English - $1.40
Lightly Played - $1.30
Lightly Played Non-English - $1.30
Played - $1.00
Played Non-English - $1.00
Heavily Played - $0.90
Heavily Played Non-English - $0.90
Damaged - $0.70
Damaged Non-English - $0.70