Guul Draz Outcast

Whenever a Swamp enters the battlefield under
your control, each opponent loses 1 life and you
gain 1 life.
{2}{b}, {t}: Put the top four cards of your library
into your graveyard, then you may return a
creature card with converted mana cost X or less
from your graveyard to your hand, where X is
the number of Swamps you control.