Tengai Shinsei

The user weaves one hand seal, in order to draw two massive meteorites from the upper atmosphere down towards a specific location on the ground. As they descend in succession along the same trajectory. if one of these meteorites is stopped, the second one, which is twice as big, then collide with the first, ensuring that they crash into their intended destination. Each creature in a 40-foot-radius sphere centered on the point you choose must make a Constitution saving throw. A creature takes 40d6 fire damage and 40d6 bludgeoning damage on a failed save, or half as much damage on a successful one.

if a creature fails this save with a natural one the damage is doubled 

The spell damages objects in the area and ignites flammable objects that aren't being worn or carried.

Can only be used by a creature with the Rinnegan