Secrets of the Core

I went close to the wall to examine the cut made by the dark blade. It had looked as thin as a hair, but the slit in the wall was about a foot thick and spanning across three meters wide. 

And when I peered into the wall, I was astonished to see it went in much deeper than what appeared on the surface.

Although it disappeared into the wall, the outline of its shape continued until I couldn't see it anymore, essentially creating a foot wide tunnel in the shape of an arc. 

The inside of the curve was extremely smooth to the touch and I wished I could regain my smaller form just so I could crawl inside it to see how far it went.

It gave me the impression the dark blade would continue sailing on for miles, at least until the magic it contained fizzled out.

It had to, considering how much of my mana Sensei had used to create it.

I looked at my status menu, at my MP bar  that had gone from [397] down to a mere [100] points, and I was shocked!