Lightning Arrow

PHB'24

Level 3 Transmutation (Ranger)

Casting Time: 1 Bonus Action, which you take immediately after hitting or missing a target with a ranged attack using a weapon

Range: Self

Components: V, S

Duration: Instantaneous

Attack/Save: DEX Save

Damage/Effect: Lightning

As your attack hits or misses the target, the weapon or ammunition you're using transforms into a lightning bolt. Instead of taking any damage or other effects from the attack, the target takes 4d8 Lightning damage on a hit or half as much damage on a miss. Each creature within 10 feet of the target then makes a Dexterity saving throw, taking 2d8 Lightning damage on a failed save or half as much damage on a successful one.
The weapon or ammunition then returns to its normal form.

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