Temptress of Beguiling Will

When Temptress of Beguiling Will enters the battlefield, gain control of target creature with
power 3 or less.
At the beginning of your end step, if you control
three or more creatures you don't own, sacrifice
those creatures: You gain life and target player
loses life equal to the total toughness of the sacrificed creatures.
"Mortal hopes are so full of futile aspirations.
No wonder they are so eager to believe the lies I tell
them."