Crackling Smite

Pure lightning energy arcs from your weapon. The next time you hit a creature with a weapon attack before this spell ends, the attack deals an extra 3d8 lightning damage and the target becomes volted.

While volted, the creature subtracts 1d4 from its melee or ranged weapon attacks as the residual electricity causes involuntary twitching. If the creature takes additional lightning damage before the condition ends, arcane electricity overloads its optical nerves, and it must make a Constitution saving throw. On a failed save, the creature is blinded until the end of its next turn. On a successful save, the creature is blinded until the start of its next turn.

Alternatively, if the creature takes fire damage before the condition ends, a concussive blast wracks the target's mind, and it must make a Wisdom saving throw. On a failed save, the creature is stunned until the end of its next turn. On a successful save, the creature is stunned until the start of its next turn.

Using a Higher-Level Spell Slot. The damage increases by 1d8 for each spell slot level above 3.