Gift of the Phoenix

Gifted by the flames of the Mythical Phoenix can cause all fire attacks and spells (including yours) to heal you instead of harming you by half of the damage plus your charisma/intelligence/wisdom modifier. In addition you can choose your own fire spells to heal instead of harming , a number of creatures equal to your level, by half of the damage.

When you are reduced to 0 hit points and thereby fall unconscious, flames of the phoenix emerge and regain half your hit points and immediately rise to your feet. Once you use this feature, you can't use it again until you finish a long rest.