Javelin of Lightning

Hurl this magic weapon and speak its command word: it transforms into a 5-foot-wide line of lightning between you and the target. Each creature in the line (excluding the target) must make a DC 13 Dex saving throw, taking 4d6 lightning damage on a failed save, and half if they pass. It 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 damage. This property can't be used again until the