Temptress Empress Jeffa

Whenever a creature enters the battlefield under
an opponent's control, clash with them. If you
win, that creature deals damage to itself equal to
its power. (Each clashing player reveals the top card
of their library, then puts that card on the top or
bottom. A player wins if their card had a higher
converted mana cost.)
Rejoice, women. You have the ultimate joy of life that
men do not know. You experience the fiercest pain and sweetest pleasure.