At the beginning of you r second main phase, look at the top X cards of your library, where X is the total amount of life your opponent lost this turn. Exile one of those cards and put the rest on the bottom of your library in a random order. You may play the exile card this turn.
Near Mint - $0.40
Lightly Played - $0.30
Played - $0.30
Heavily Played - $0.20
Damaged - $0.20
Near Mint Non-English - $0.40
Lightly Played Non-English - $0.30
Played Non-English - $0.30
Heavily Played Non-English - $0.20
Damaged Non-English - $0.20