Drain the Meek

Starting with you, each player chooses one creature he or she controls, then sacrifices every other creature they control. For as long as Drain the Meek remains on the field, the chosen creature gets +X/+X where X equals the combined power of each creature sacrificed under their control.
"I will not be contained. I will not be killed. Each soldier holds a bit of my power, but when released from undeath they will restore me to my full strength."
-Zarth, the Evermore