Rei the Frail

Rei the Frail has ward {2} as long as it's tapped.
You must exert Rei the Frail as it attacks.
(It won't untap during your next untap step.)
Whenever you exert a creature, you may reveal
the top card of your library. If you do, put that
card into your hand. You lose life equal to its
converted mana cost.