Ztask, Discoverer of the Lost

When Ztask enters the battlefield, exile
all cards from your graveyard.
If a card would be put into your graveyard from anywhere, exile it instead.
{3} {t}: Mill three cards. Then, you may put
a land card from exile on the battlefield
under your control and choose a creature
in exile. You may cast the chosen card
until end of turn.