"Sir, the four colleges of First University and the methods you just mentioned..."
Taking advantage of the brief pause after Mr. Wu finished his warning, Zheng Qing immediately spoke up, asking about the confusion he had kept buried in his heart.
"I'm glad you noticed that. Just as you thought, our establishment of the four colleges was partly a historical choice and partly a practical one. Strengthening the traits possessed by each college's students is the practical choice for facing demons."
"Truth-seeking, honor, victory, faith... While these concepts mark your identities, they also strengthen the barriers in your hearts, making you more steadfast when facing the erosion of demonic aura."
"Of course, aside from the difficult path of 'conviction,' there is another, relatively simpler method of resisting demonic corruption."
"There is a kind of tree in this world. Its roots burrow deep into the Earth Vein, while its branches and leaves gather Spiritual Energy. It is called Xuanhuang Wood. The fruit it bears is called Mystic Yellow Fruit. It can purify demon bloodlines, and it can also strengthen a wizard's ability to resist the erosion of demonic aura... Few people know about the latter. Most wizards, demons included, only know that Xuanhuang Wood uses Demon Flesh as nourishment and can 'clean up' demonic contamination of the environment cleanly and quickly."
"Xuanhuang Wood is exceedingly rare. Extremely, extremely rare. The Alliance's only known remaining tree grows in the Black Prison. If I remember correctly, it should be twenty-four thousand years old this year... Its fruit should be ripening soon as well."
Zheng Qing's mouth slowly fell open.
Long ago, when he and Xiao Xiao had discussed where the professors had gone, everyone had turned their attention to the Black Prison. At the time, even Zheng Qing's worst guess had only been