This helm appears to be made of heavily pocked and dented bronze but its walls are incredibly thick. After further inspection you realize that this helm is actually carved from metallic rock which would explain why it’s so heavy.
As an action while wearing this helm you can create 1d4+1 tiny meteors in your space. They float in the air and orbit you tightly for the next minute. As a bonus action you can expend a meteor, sending it streaking toward a point you choose within 120 feet of you. Once a meteor reaches its destination or impacts against a solid surface, the meteor explodes. Each creature within 5 feet of the point where the meteor explodes must make a DC 14 Dexterity saving throw, taking 2d6 Fire damage on a failed save.
After a meteor has been orbiting you for 1 minute it will spontaneously explode. You must make a collective saving throw against any of the meteors that explode, taking 2d6 Fire damage per meteor on a failed save, or half on a successful one.