Juan Carlos III, False Prophet

Whenever this creature transforms into
Juan Carlos III, False Prophet, mill 10 cards,
then it becomes a copy of target demon in
your graveyard. It's a human cleric, in
addition to it's other types, with
"{w/b}{b}: Until end of turn, this creature
gains 'When this creature dies, return it
to the battlefield tapped under it's owner
control.' "