User blog comment:Stbk22/Possible Power up's/Techniques for then new group DxD/@comment-1884090-20140204160946/@comment-24331253-20140205023239

@B214;

Though I don't think Rias's proficiency at using the powe of destruction could be as good as her brother Sirzechs because she is more of a wizard power type unlike Sirzechs who is wizard technique type, I don't think it means that she didn't inherit the Gremory's magic talent. Their area of talent may just be different.

Also both the power of  destruction and dragon shot do not have a form, it is the wielder that gives them form. Afterall Sizechs shapes his power of destruction into spheres. To be exact, the most common form given to power be it magic, demonic powers, holy powers, dragon powers is the form of a sphere.