Lunar Princess Ranni

Ward - Discard an Enchantment, Instant or Sorcery.
Whenever you cast your second spell each turn, each opponent mills two cards. When one or more cards are milled this way, exile up to one enchantment, instant or sorcery card with equal or lesser mana value than that spell from an opponent's graveyard. Copy the exiled card. You may cast it without paying its mana cost.