Paragon of Holy Flame

Whenever another red or white creature enters
the battlefield under your control, it deals 1 damage to target player and you gain 1life.
{r}{w}, {t}: Another target red or white creature
you control gains undying until end of turn.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)