Elemental retaliation

After taking damage from an attack that deals; Acid, cold, fire, force, lightning, poison, or thunder. You envelop yourself in evocation energy from that attack. Those who damage you with a melee attack for the next round take 1d10 damage of the type you were damged by. The effect ends at the end of your next turn.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d10 for each slot level above 1st.