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.)
Wildcall has 3 listed printings; the most valuable is the printing from UGIN at US$1.00 on TCGplayer's market price. Prices below are the cheapest in-stock listing in the United States.
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