Anivia, The Cryophoenix

Flying.
Whenever Anivia, The Cryophoenix enters the battlefield or attacks, put a Frost counter on each
creature your opponents controls.
{2}{u}{u}{t}; Anivia deals X damage to each creature
with a Frost counter, where X is the number of
Frost counters on it. Tap those creatures and you
may draw a card for each creature that dies this
way.