Crown of Leadership
Wondrous item, very rare (requires attunement)
This crown consists of a thin band of gold adorned with ten flawless diamonds. While wearing this crown, your Charisma score changes to 18. The item has no effect on your Charisma if it is already equal to or greater than 18.
In addition, you can use your action to speak the crown’s command word. For 1 minute, all friendly creatures within 10 feet of you are immune to being frightened or charmed and gain temporary hit points equal to twice your Charisma ability modifier at the start of each of their turns. Once used, this property of the crown can’t be used again until the next dawn.