Arcane Cataclysm

You conjure orbs of magical energy that plummet to the ground at three different points you can see within range. Each creature in a 40-foot-radius sphere centered on each point must make a Dexterity saving throw. The sphere spreads around corners. A creature takes 11d12 force damage on a failed save, or half as much damage on a successful one. A creature in the area of more than one arcane burst is affected only once.

The area of each arcane burst then acts as an antimagic field for 1 hour. Both you and spells you cast are unaffected by these fields.