Good enough. [He licks his finger and flips over the page.] From what I heard, the arte wasn't fully developed in time to be used in battle, but while it was being researched, there were a number of fonic artes that branched off from the main theory. Most of them were too unstable to be used, but two of them are mention in the book. I don't know if they're worth trying, but they're mentioned repeatedly throughout the book. It's powerful stuff.