The Silver Specter

Whenever a creature attacks you or a
planeswalker you control, that creature doesn't
untap during its controller's next untap step.
At the beginning of each opponent's end step,
that player loses life equal to the number of
tapped permanents he or she controls.
{u}{b} or discard a card: Regenerate The Silver
Specter. She gains hexproof until end of
turn.