Crystal explosion

You ceate 2  Flying cristalls  in an area. . They create white, erupting crystals through the fusion of earth and water magic. The crystals grow until they explode. The stronger the magic, the stronger the crystals become. Each crystal causes a penetrating blast through armor and bodies. The shards within the explosion radius cause significant damage. A successful dodge save halves the damage taken with a Dexterity of 14. With low spellcasting, the higher the spell's power, the better one must be able to dodge. Dexterity 14/ Dexterity 15/ Dexterity 16. 

This spell’s damage increases by 2d10 when you reach 5th level (4d10), 11th level (6d10), and 17th level (8d10).