Eldritch weapon

Crackling energy surrounds the weapon used in the spell. Make a melee  attack against one creature with in range. On a hit, in addition to the weapon damage the creature takes 1d4 force damage.

The spell does more damage when you reach higher levels: 2d4 at 5th level, 3d4 at 11th level, and 4d4 at 17th level.