Helm of the Platinum Dragon

Wondrous item, very rare (requires attunement by a dragonborn of good alignment)

This magical platinum helmet has been blessed by a powerful, holy dragon. While wearing this helmet, you gain a +1 bonus to AC and saving throws, and when you use your breath weapon, you can choose to exhale a holy blue plume of healing energy instead. When you do, this breath weapon deals radiant damage, evil-aligned hostile creatures within the area have disadvantage on the saving throw, and any friendly creatures in the area regain a number of hit points equal to your breath weapon's damage dice instead. This property of the helm can't be used again until the next dawn.

I will breathe new life into the world instead of destruction. I will bring about peace instead of war. My friends will know the kindness of dragons, and we will be stronger for it.