Crystal Nova

3rd-level evocation

Classes sorcerer, warlock, wizard

Casting Time: 1 action or one reaction, taken in response to being damage by a creature within 60 feet that you can see

Components: V, S, M (glass shards)

Range: Self (20-foot radius sphere around you)

Duration: Instantaneous

You curl up or shudder for a second, before bursting forth a dazzling explosion of scintillating light and crystalline shards around you. All creatures within a 20-foot-radius around you must make a Dexterity saving throw. On a failure, the blasts of light and crystal shards inflict 3d6 psychic and 3d6 radiant damage, half as much on a successful save. You are not affected by this spell. Creatures are never killed by this spell, only knocked unconscious.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd. You may freely choose whether the increased damage is psychic or radiant damage and freely distribute the d6s granted by higher spell slots among the two damage types.