Javelin of Lightning

When activated and thrown it becomes a bolt of lightning 5' wide and up to 120' long. Each
creature in the line except you and the target
makes a DC 13 Dex save, taking 4d6 lightning if
failed and half as much on a success, it then turns
back into a javelin.
Make a ranged weapon attack, on a hit the target
takes damage from the javelin plus 4d6 lightning damage. The lightning can't be used again
until the next dawn, but the javelin still counts as
a magic weapon.