Once the Soul Guide and the Wan Ming Incarnation are formed, they are independent and have no causal relationship; no Immortal Skill at the current stage can trace them.
This is also one of the troubles with the Soul Tower—it is why the Wan Ming Immortal Sovereign appears and disappears like a ghost, yet knows countless news of the Immortal Realm and influences the major trends of the realm.
The Soul Sutra and Soul Guide can also be found in the Age Candle Immortal Court.
But Han Yi did not seek them, nor did he practice the Soul Sutra, because he worried that if he practiced the Soul Sutra, he would be unable to infiltrate the Soul Tower.
Moreover, before this, there were not a few immortals who practiced the Soul Sutra using intercepted Soul Guides, but none of these practitioners of the Soul Sutra could find the slightest clue through this method.
In Han Yi's view, this was akin to unauthorized access.
