Enchanting Rune Whale

Submerge {u/b}{2}:Exile this spell face down from your
hand or the battlefield and return it to the battlefield anytime for it's submerge cost. Exile all auras attached
to this creature and reattach them when it enters the battlefield. Whenever a spell is submerged
create a 0/2 Depths token with Shroud.
When Enchanting Rune Whale enters the battlefield return target creature to
it's owner's hand.