Celestina, The Divine Shield

Flying, Indestructible, Defender
As long as your devotion to white and blue is less than seven, Celestina isn't a creature.
At the beginning of your end step, create a X/X Avatar creature token with defender where X is equal to your devotion to white and blue.
{2}{w}{u}, {t}: Creatures you control lose defender
and gain vigilance until end of turn.