Sitting Down

"What a powerful attack…!" Master Vertol exclaimed. "I have never experienced such pain in my entire life!"

Yet a grin emerged on his face. "Not enough to overcome the Yin-Yang Shield, I'm afraid."

Rui smiled. "Say, do you know how the technique works?"

"Of course," he snorted. "The shield is born from the harmony of my inner yin and the outer yang. The harmony of yin and yang gives rise to all things in the universe."

Rui stared at him knowingly. 

The fact that an empowered Reverberating Lance and the Yin-Yang Shield produced interference patterns that were normally only produced by the superposition of two sound waves necessarily meant that there were two sources of vibrations.

One was, of course, Reverberating Lance.

The other could only be the Yin-Yang Shield.

The source of its defensive power was sound vibrations.

Yet, that wasn't the whole explanation.

It didn't explain many things.