Szitek, the Lethal Desert

Szitek enters the battlefield tapped.
{1}{t}: Add {b}{w} to your mana pool.
{b}{w}{t}: Sacrifice a creature, gain 1 life and
draw a card.
Centuries ago, Szitek was part of the great ocean.
Years passed by and it dried more and more. At least,
the giant whales went up to the sky.