Armor of Artifice

You temporarily embue your armor with a charged force, manifesting as an electrical charge. You gain 5 temporary hit points for the duration. If a creature hits you with a  melee attack while you have these hit points, that creature takes 1d6 lightning damage.

At higher levels. When you cast this spell using a spell slot of 2nd level or higher, the temporary hit points increase by 5 and the damage increases by 1d6, per each spell slot

*this is an artificer reflavor of Armor of Agathys*