Petak, track chaser

{t}: Look at the top 3 cards of your library. You
may exile a creature card from among them.
Shuffle your library. You may cast the exiled
card for as long as it remains exiled.
{g}{g}: Untap Petak
Whenever you cast a card exiled with Petak, put a
+1/+1 counter on it. It gains trample and haste
until end of turn.