Li Shiming had not expected that the hardest to cultivate would actually be the 'Silver Winged Spirit Gu Insect'.
When it came to cultivating spiritual insects, he was extremely experienced; even those 'Eternal Water Bears' had all been cultivated by him to Half-step Fifth Grade.
But the 'Silver Winged Spirit Gu Insect' was different; even with the Gu Feng Sect's inheritance, they had only ever cultivated 'Silver Winged Spirit Gu Insects' to Late Stage Fourth Grade.
In fact, in the Gu Feng Sect's history, not to mention Late Stage Fourth Grade 'Silver Winged Spirit Gu Insects', even Mid Fourth Grade 'Silver Winged Spirit Gu Insects' had rarely been successfully cultivated.
Let alone Half-step Fifth Grade 'Silver Winged Spirit Gu Insects'; the Gu Feng Sect simply had no inheritance in this area.
