Chromatic Strike

You imbue one melee weapon you are using with elemental energy. You choose acid, cold, fire, lightning, poison, or thunder damage. Until the end of your turn the next time you hit a creature with that weapon the target take an additional 2d8 damage of the chosen type.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d8 for each slot above first.