Climate Angel

Flying, lifelink, first strike
Whenever a creature enters the battlefield under
your control, you may pay {x}{r/w}{w/u}. If you do,
deal X damage to target creature or player and
you gain X life.
If Climate Angel were to leave the battlefield, you
may pay {5}{r/w}{w/u}. If you do, create two 4/4 white
angel creature tokens with flying.