Blood Boil

Choose one creature in sight range. If that creature has blood, they take 1d8 fire damage and 1d8 necrotic damage when you cast the spell as you start to boil their blood flowing through there veins. Until the spell ends, you can use a bonus action on each of your subsequent turns to cause this damage again.

The creature must succeed on a Constitution saving throw or have disadvantage on attack rolls and ability checks until the start of your next turn as the pain courses through their body.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d8 for each slot level above 2nd.