"Let's start with your first question. It concerns the nature of Yan Hua."
Professor Yi showed no impatience. If anything, he explained in greater detail—perhaps Black Cat's question had awakened his professorial habits, or perhaps teaching someone clad in the guise of a Legend was an honor even for a Grand Diviner, one that might earn him a little Legendary Status.
He even slowed his chanting and the turning of the Roster's pages, giving Black Cat more of his attention. "We don't know Yan Hua's True Name, but we can use its characteristics to narrow it down to a range of strong possibilities..."
An arm emerged from beneath his ribs and gestured in the air. "For example, Yan Hua's visible form has a body made of 'paper,' and when it dies, it leaves behind 'fireworks' and 'charred marks.' Those traits let us rule out water, metal, and earth first, narrowing it down to fire and wood. More specifically, Yan Hua is a life-form that is 'seemingly dead yet not alive,' so its fire or wood should be yin-aligned. We can narrow the range further to 'yin wood' and 'yin fire.' That range is what you called its 'classmates.'"
Black Cat fell into thought.
He nodded slightly.
Terms such as "yin wood" and "yin fire" belonged to an obscure body of knowledge used by old-school wizards—one that almost only Diviners studied now—to classify a wizard's "makeup," or rather, their "attribute of truth."
Ancient Wizards believed that all magic a wizard below the Legendary Grade could master fell within yin, yang, and the five elements. The Heavenly Stems divided those elements into yin and yang, and together they could encompass every truth in the world.
Take vampires, for example. Their nature belonged to Lunar Yin. They hid in the night and prolonged