Eye of the Creator

+1: Add 5 mana of any color to your mana pool, spells cast by using this mana are exiled instead after they are played or destroyed
+2: You may play a spell from exile by paying life equal to its mana cost
-10: Each player mills the top 5 cards of their library, then exile each player's graveyard, gain 1 life for every 2 cards exiled this way