Ur Dragon, Cosmic Overlord

When Ur Dragon, Cosmic Overlord enters the battlefield look through each opponents library and exile a card from it face down, you may look at those cards and cast them using mana as though it were mana of any color.
When Ur Dragon, Cosmic Overlord dies, place all permanents fr graveyards and exile onto the battlefield under your control, exile the at the beginning of the next turn's upkeep.