Dragonband

This metal bracelet hangs loosely from a wrist or ankle and is made from either brass, bronze, copper, gold, or silver wire. The clasp is cast in the shape of a metallic dragon's head matching the metal used in the rest of the band. While wearing the band, you can use an action to speak its command word and cause it to unravel and shatter, destroying the bracelet. When it does, it releases a powerful blast of energy in a wave around you. Each creature within 20 feet of the band other than you must make a DC 15 Dexterity saving throw, taking 10d6 damage on a failed save, or half as much damage on a successful one. The damage type is determined by the type of metal used in the band, using the table below.

Metal types: