Hellish Rebuke

Casting Time: 1 reaction, in response to being damaged by a creature within 60 feet
Range: 60 feet-Components: V S
You point your finger, and the creature that damaged you is momentarily surrounded by hellish flames.
The creature makes a Dex saving throw.
It takes 2d10 fire damage on a failed save, or half a successful one.
•At Higher Levels:
When you cast using a spell slot of 2nd level or higher, the damage increases by 1d10 for each slot level.