Crackling Hands

As you hold your hands with thumbs touching and fingers spread, a small swarm of electricity shoots forth from your outstretched fingertips. Each creature in a 15-foot cone must make a Dexterity saving throw. A creature takes 3d6 lightning damage on a failed save, or half as much damage on a successful one.

Those in metal armor have disadvantage on their save.

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