Barghast Gathering

When Barghast Gathering enters the battlefield and at the beginning of combat on your turn, exile the top card of your library.
If it is a nonland card with mana value less
than or equal to the greatest power among creatures you control, you may cast it without paying its mana cost. If you don't, put a +1/+1 counter on target creature you control.
{2}{r}{g}: Return a card exiled with Barghast Gathering to its owner's hand.