Hellish Rebuke

You point your finger, and the creature that damaged you is momentarily surrounded by hellish flames. The creature must make a dexterity saving throw. It takes 2d10 fire damage on a failed save, or half as much damage on a successful one.

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.