Hargrave The Reborn

Haste, Unlockable, Ward {p/b}
When Hargrave The reborn is cast from the
command zone, sacrifice it. Each player mills {x} cards.
Whenever you play a permanent from
a graveyard, return Hargrave The Reborn to the battlefield with +X/+X where {x} is equal to
the number of cards in your graveyard.