Felene, the Famished

{b}, Exile a creature card from each opponent's graveyard, then put X +1/+1 counters on Felene.
the Famished where X is the number of creatures exiled this way. Activate this ability only once
and only during your turn.
"We follow armies just as crows follow wolves. Waiting
in the shadows until the battle is over. Then the feast
begins."