Chromatic Smite

When you cast this spell you choose acid, cold, fire, lightning, poison, or thunder and temporarily imbue your weapon with that element. The next time you hit a creature with a melee weapon attack during this spell’s duration, you release the element stored by the spell, and the attack deals an extra 3d6 of the chosen elemental damage to the target. Additionally, some of the elemental energy can strike one creature that you can see within 5-ft of the initial target. The second creature takes damage of the elemental type equal to your spellcasting ability modifier.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the melee attack's bonus elemental damage increases by 1d6.