Awakening of the Old God

As you cast this spell, you may exile your hand.
If you do, it costs {2} less to cast.
Choose a creature you control, then exile all
other nonland permanents.
"One day he will awaken from their centuries-long
slumber! That day will be a glorious one, for only the
most devoted will ascend as this sinful world is
eradicated and its dust is blown away, never to be
regarded again!"