Murasaki Shion, Smug Witch

Flying
Boast — {1}{b}: Draw a card. (Activate this ability
only if this creature attacked this turn and only once
each turn.)
At beginning of each opponent's upkeep that
player loses 1 life for each card fewer than cards
in your hand.
Whenever Murasaki Shion deals combat damage
to a player, that player discards a card.