Gravity Sinkhole

A 20 ft radius sphere of crushing force forms and
tugs at the creatures. Each creature in the sphere
makes a Con save. On a failure save, a creature
takes 5d10 force damage and is pulled towards
the center of the sphere, ending in an unoccupied
space as close to the center as possible (even if
that space is in the air). On a success, it takes half
as much damage and isn't pulled.
At Higher Levels. Each extra spell slot increases
the damage by 1d10.