Mildrith, Tomb Historian

At the beginning of your end step, you may exile
a card from your graveyard and put a shadow
counter on it. If you do, you draw a card.
When Mildrith, Tomb Historian leaves the
battlefield, you may choose a card you own in
exile with a shadow counter on it. If you do,
put it into your hand and you gain life equal
to its mana value.