Look at what is actually contained within MW on a hindu level, what she is an amalgamation of in identities, all contained in the mask of MW. Now imagine Harry, as Harry, containing countless... Say from the popular theory of Dark Hallow on DR. You are what you eat but what you eat becomes a part of you, So all that energy, all those beings are identified under the original. They became Harry Blackstone Copperfield Dresden in truth. Now imagine calling directly upon such an amalgamous unstable being with literally thousands of forms ad the combined might and willpower of all of them while keeping that Mortal spark of choice....
You CAN'T contain it, you can't stop it. Conjure by it at your own risk...