Glorb

Flying, First Strike
When Glorb Enters the battlefield, other creatures on the battlefield under your control
gain +0/+3, and Menace, you gain 3 life. When a creature under your control dies, create a */* green alien creature token where * is equal to half the power of the creature that died.
When Glorb leaves the battlefield, choose a card
from any graveyard and put it into your hand or
into play.