<Soul-Chasing Spirit Butterflies and the Destruction of Great Xia's Great Wilderness Sect> was a freely accessible article. Its author's alias on the Mountain of Light was unknown, and it had been published anonymously. Zhang Tie spent more than ten minutes reading the article carefully three times, then fell into deep thought.
Soul-Chasing Spirit Butterflies were a peculiar species that lived in the abysses of the Underground World. They possessed an extremely unusual trait: if someone obtained one of their eggs, then after it hatched, any knight-level person need only feed the Soul-Chasing Spirit Butterfly a little of their own blood for it to establish a wondrous mental connection with that knight. It could then accept the knight's commands and help them locate or lock onto someone.
When a person moved about within a certain area or space, they left behind their scent. Trained hunting dogs and military dogs could easily identify those scents and follow them to find their owner. Such scents came from a person's body, but beyond them, every person actually possessed another, invisible scent. This scent originated from certain inner qualities; it was the "scent" emitted by one's spiritual energy, or rather, one's soul. The most formidable thing about Soul-Chasing Spirit Butterflies was that, like hunting dogs, they could sense this invisible "scent" on a person and use it to find them.
That was where the Soul-Chasing Spirit Butterfly's greatest value lay.
Countless studies had confirmed that as long as a person had stayed somewhere, even after they left, the "soul scent" they left behind would not dissipate for seventy-two hours. If a Soul-Chasing Spirit Butterfly was allowed to circle the place where that person had stayed, it could accurately identify and firmly remember that person's "soul scent." Then, within a range of three hundred kilometers, it