Uncle Gary, The Unifer

Whenever you cast a legendary spell from your
hand, exile cards from the top of your library
until you exile a legendary nonland card with
lesser mana value. You may cast that card
without paying its mana cost. Put the rest
on the bottom of your library in a random order.
Gary was one to bring a smile to everyone's
face and always there to lend a hand no
matter how tough.