The White Stone of Ancients

Defender
At the end step of the turn this card dies, if it is
still in the graveyard, reveal cards from the top
of your library until you reveal a white dragon
creature card, put that card onto the battlefield,
then put the rest on the bottom of your library
in any order.
Flashback {w} (You may cast this card from
your graveyard as a sorcery that reads 'Return
target white dragon creature card from your
graveyard to your hand' for its flashback cost,
then exile this card.).