Empower

You grant powerful energy to yourself or a target within range. Until the end of your next turn, the target emanates electrical energy which arcs out in a 10ft radius. Any creature that begins it's turn within range of the empowered target must make a constitution saving throw. The creature takes 3d6 lightning damage on a failed save or half as much on a successful one.

In addition, the empowered target adds 3d6 lightning damage to any melee attack made while empowered regardless of a successful hit.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the number of rounds a target is empowered increases by 1 for each slot level above 3rd.