Lifebound Gu is not something everyone can have, especially for mutual cultivation that acts like "electric potential difference." Only those with a "Spiritual Heart Source" or "Spiritual Lotus Body" can be Holy Maidens, otherwise, it's just one side overpowering the other.
Especially since Lifebound Gu can only be imprinted once in a lifetime, much like the Four Gates Broken Running Horse, refining must rely on one's own effort. As such, cross-realm refining is bound to be difficult, and if the realm difference is too great, not only will it be impossible to refine, it may also result in backlash.
Refining a Zenith Great Demon at a low realm is too difficult, and the value of Wolf Smoke Belt Running Horse is too low.
Therefore, considering the balance between gains and costs, the best choice is to contract a Hunting Tiger Gu Worm during Wolf Smoke, thereby quickly passing through the Hunting Tiger Realm!
