Covolt Scythe

Weapon (glaive), rare (requires attunement)

This jagged scythe is forged with covolt, an elemental blue metal that carries storm-like properties. When you hit a creature with an attack using this magic weapon, it takes an extra 1d8 lightning damage. Once on each of your turns when you hit a creature with this weapon, you can choose a different creature within 10 feet of the target. That creature must succeed on a DC 15 Dexterity saving throw or take 1d8 lightning damage as an arc of electricity lashes out at it from the original target.

Some storms you simply can't contain.