The Ancient Awakening

Whenever you cast a spell from your graveyard,
create a 6/6 blue Leviathan creature token with
hexproof.
{4}{u}, {t}: Each instant and sorcery card in your
graveyard gains flashback until end of turn. The
flashback cost is equal to its mana cost. (You
may cast it from your graveyard for its flashback
costs. Then, exile it.)