Aura the Guillotine

When Aura the Guillotine enters the battlefield,
gain control of target creature for as long as you control Aura.
{t}: Auserlese — You and target opponent roll a
d20. The player that gets the lowest number
sacrifices a creature with converted mana cost
4 or more and loses 5 life.
"You may be a talented mage, but your mana
is nothing special."