The first time you hit with a melee weapon attack during this spell’s duration, your weapon pulses with Lightning that glows with light within 30 feet of you, and the attack deals an extra 1d6 lightning damage to the target. Additionally, if the target is a creature, it must succeed on a Constituion saving throw or be stunned until the end of it's next turn.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the initial extra damage dealt by the attack increases by 1d6 for each slot.