Amulet of Storms (5e Equipment)
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Wondrous Item (Amulet), artifact (Attunement by any alignment)
The amulet of Storms is an artifact of immense power, imbued with lightning. Just as successive lightning strikes are considered "Lucky", this Amulet manages to bestow luck upon adventurers, showing up in places it has no business being.
Eye of the Storm. When worn, attacks with melee weapons apply damage dealt to all enemies within 10ft of the attacker as lightning damage. Creatures must make a Dexterity save of DC 8 + Your Proficiency + Your Attack Modifier. On success, they take half damage.
Destroying the Amulet of Storms. The Amulet can be destroyed by being submerged in the waters of the Eternal Plane of Water for one hour.