Alva & Jurith, Flamebound

Flying, Vigilance
{w}{w}: Choose a color. Until end of turn whenever
a source of the chosen color deals damage, put a
+1/+1 counter on Alva & Jurith, Flamebound
{r}{t}: Remove X counters from Alva & Jurith,
deal X damage divided as you choose among any
number of targets. If a creature dealt damage this
way would die this turn, exile it instead.