Blood Boil

You force your gaze upon a creature of your choice that you can see within range as the creature’s blood begins to boil. The target must make a Constitution saving throw. The target takes 4d8 fire damage on a failed save and is incapacitated for one minute, or half as much damage on a successful one and is not incapacitated. If the creature fails this spell save, they may reattempt the saving throw at the end of each of their subsequent turns. On each subsequent failure, the target repeats this damage. This spell has no effect on any creature without blood.

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d8 for each slot level above 4th.