Wondrous Item

Rare Requires Attunement

You gain a +1 bonus to AC if you’re wearing no armor while wearing this helmet. You can still use a shield and gain this benefit. In addition, while wearing no armor, the helm becomes suffused with glory and glimmers for 1 minute whenever you roll a 20 on an attack roll. While the helm is glimmering in this way, you gain temporary hit points at the start of each of your turns equal to half your level, and friendly creatures within 10 feet of you can’t be frightened.