Arc Lightning

A bolt of lightning blasts forth from you and strikes a target within range.  After hitting the original target, the lightning arcs to the nearest creature within 10 ft.  If there are no creatures within range of an arc, then the lighting will arc to the nearest metal object (5ft cube or larger) within range.  The lightning continues to arc from target to target (creature or object) in this way until it has struck a number of targets equal to your spellcasting modifier or there are no new targets within range of an arc.

Each creature struck by lightning must make a Dexterity saving throw.  A creature takes 8d6 lightning damage on a failed save, or half as much damage on a successful one.

 Arcs can only occur if there is direct line of sight between the targets with a minimum 1" diameter hole to pass through.  If there are multiple targets of equal distance from the source of an arc, then the caster chooses which target is struck by the arc.  A target can only be struck by lightning once during a single casting of this spell.  Objects struck by the spell take damage as appropriate, consult your DM.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.