There was a saying: Iron Skin Gu, meat Gu, Copper Bone Gu, these kinds of inexpensively made Gu insects that don't consume much spiritual energy were indeed somewhat unreasonable.
They didn't consume much spiritual energy, yet their defense was high.
On such a battlefield, it was rare to encounter cultivators who attacked with full force. After all, people needed to conserve a great deal of spiritual energy for defense as well.
Thus, the conventional flying swords or lightning, fire, and Wind Blades didn't actually cause particularly significant destruction.
Only top-tier Great Sects might be able to cultivate such terrifying scenes where, upon an order, countless flying swords filled the sky.
Clearly, this was not very applicable in Nanli, at least not within the scope of the Foundation Establishment Realm.
Even for a major tribe, there were only about a dozen Foundation Establishment cultivators, and it's estimated that only half of them used tribal Gu insects.
