End of the World Meteor Swarm

Xiothun, Destroyer of Worlds uses spheres of pure energy to bore away at a planet, to create room for it to burrow to the core. 

8 spheres of pulsating dark energy strike the ground in different locations within a 5 mile radius. Each creature within a 100-foot-radius of each sphere must make a Dexterity saving throw. The damage can spread around corner, under objects, and throw small gaps. A creature takes 20d20 necrotic damage and 20d20 bludgeoning damage on a failed save, or half as much damage on a successful one. A creature in the area of more than one fiery burst is affected only once. 

The spell damages objects in the area. The ground where each sphere lands is devastated and is considered difficult terrain.