Javelin of Lightning

5 ft.; 1d6+3 piercing; Magic weapon
Hurl it, speak command word, transforms into a
bolt of lightning, forming a line 5 ft wide that
extends out from you to a target within 120 ft.
Each creature in the line excluding you and the
target must make a DC 13 Dex saving throw,
taking 4d6 lightning dmg on a failed save, and
half as much damage on a successful one. The lightning bolt turns back into a javelin when
it reaches the target.