Manifest the top card of your library, then put a +1/+1 counter 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 - £0.30
Lightly Played - £0.30
Moderately Played - £0.20
Heavily Played - £0.20
Damaged - £0.10
Near Mint Non English - £0.30
Lightly Played Non English - £0.30
Moderately Played Non English - £0.20
Heavily Played Non English - £0.20
Damaged Non English - £0.10