Amaterasu

Description: Amaterasu is a Mangekyō Sharingan dōjutsu, and the highest level of Fire Release. It produces black flames at the focal point of the user's vision. In most situations, this makes Amaterasu impossible to avoid. However, techniques of extreme speed allow the avoidance or interception of the jutsu after it has been cast. Amaterasu burns any material until nothing but ash remains. It cannot be extinguished through most conventional means and will continue burning until the target is completely incinerated.

Mechanics:

• When you cast Amaterasu, choose a target within sight. The target must make a Dexterity saving throw.
• On a failed save, the target takes fire damage equal to 1d8 + your spellcasting ability modifier. On a successful save, the target takes half damage and removes the flames before they spread.
• Amaterasu persists on the target until the flames are extinguished or removed somehow or until it burns to ash.
• At the start of each of the target's turns while affected by Amaterasu, it takes an additional 1d8 fire damage.
• The casting of Amaterasu requires 3 Ki points and 1 hit point if you are a monk or expend 3 hit points if you do not have Ki points.