Javelin of Lightning

When you hurl it and speak its Command Word, it turns into a bolt of lightning, forming a line 5ft wide that extends out from you to a target within 120ft. Each creature in the line excluding you and the target must make a DC 13 Dex saving throw, taking 4d6 lightning damage on a failed save, and half on a success. The Lightning Bolt turns back into a Javelin when it reaches the target. Make a ranged weapon Attack against the target. On a hit, the target takes damage from the Javelin plus 4d6 lightning dam