The Red Priestess, Melisandre

Creatures you control have hexproof.

{r}{w}, {t}: Look at the top three cards of your library. Reveal a card from among them and
put it into your hand. Put the rest into your graveyard.

Whenever a creature you control dies, gain 1 life. If that creature was sacrificed, gain 2 life
and put a +1/+1 counter on target creature you control.