Basic Rules , pg. 250
Hellish Rebuke (Tiefling racial ability)
2-level
Evocation
Casting Time 1 Reaction
Range 60 ft
Duration Instantaneous
Components V, S
Racial Ability, available once per long rest
Does NOT use a spell slot
Damage Type: Fire
Saving Throws: Dexterity
Description: 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 3d10 fire damage on a failed save, or half as much damage on a successful one.
Class(es): All