Spellstorm

You call upon wild, roiling magic to pelt an area within range of the spell. All creatures within 15 feet of the point must make a Constitution saving throw. On a failure they take 20 (8d4) force damage, or half as much on a success. The area also becomes filled with untamed magical residue for the duration of the spell. If a creature tries to teleport or cast a spell while in the area, they must make a Constitution saving throw. If they fail, the teleport or spell fizzles and the spell slot is wasted.

At higher levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 2d4 for each slot level above 3rd.