Selizdan Seeker

{t}, Choose one—
•Add {w} or {g}.
•Look at the top card of you library. You
may exile it. If you do, sacrifice a creature
and you gain 4 life. If you don't, put it into
your hand.

"Don't try your luck—that's what I always say—
but there's a difference between that and searching for
it."-Hakke Selizdan, the Caller