Crystal Grenade

When you cast this spell as a bonus action, you imbue arcane power into the crystal used in spellcasting, causing it to become unstable. You can throw the unstable crystal in the same action, and when it comes into contact with a solid object, it explodes in a 20 ft. radius sphere. Creatures within the radius of the explosion must make a Dexterity saving throw. On a failed save, any creature within the radius takes 5d6 force damage as well as 2d4 piercing damage, or half as much on a successful save.