Bloodboon

You thrust your arm into the body of the distant Formless Mother, and draw bloodflame from her, scattering it before you. Each creature in a 15-foot cone must make a Constitution saving throw or take 4d6 fire damage.
Flames linger in the area until the start of your next turn. Each creature that enters the area for the first time on a turn or starts its turn there takes 1d4 fire damage and rolls a d20. If the creature rolls a 1, it takes 5d4 piercing damage as its blood hemorrhages from its body.