Hunt for Everlast

When you cast Hunt for Everlast, any player may discard his or her hand. If a player does, counter Hunt for Everlast.
Until end of turn, if you would cast an exiled face-down card without paying its mana cost, instead cast a card from your graveyard without paying its mana cost and and put the exiled face-down card on the bottom of your library. If cards cast this way would enter the graveyard from anywhere, exile them instead.