Thunderblade

You touch a creature and enhance a melee weapon they’re currently wielding with thunderous energy. Their next melee attack deals an additional 2d6 lightning damage, and if there are any creatures within 5 ft. of the target a bolt of lightning extends to them, dealing 1d6 lightning damage to them additionally(excluding the attacker). If there are multiple creatures within 5 ft. of the target determine who take the additional damage randomly. Once the attack is made the spell ends. If no attack is made before the spells duration, the spell ends. If you cast the spell on a creature who is not wielding a melee weapon, it has no effect.

At Higher Levels: For each level the spell is cast above 2nd the attack deals an additional 1d6 lightning damage to the target and too the creature within 5 ft. of it if is there is one.