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.
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.
RollQuest ships the D&D 2014 SRD as a content pack, on a 5e character sheet that does the maths - roll from the sheet and let the numbers work themselves out. Free to start.