Restless Cavalier

Restless Cavalier has vigilance as long as there are
at least 10 cards in your graveyard.
When Restless Cavalier enters the battlefield, put
the top 3 cards of your library into your
graveyard. Restless Cavalier gains a +0/+1
counter for each creature put into the graveyard
this way.
When Restless Cavalier is put into the graveyard
from play, gain life equal to its toughness.