Asteria, The Flamebearer

Flying, vigilance, lifelink
Blaze - At the beginning of your combat
step, if an opponent has lost 3 or more life
this turn, creatures you control gain +1/+1, lifelink and vigilance.
If she is a torchbearer, she carries with her a
blaze of glory, and all who follow will bask in
her radiance.