Terrifying Discovery

Yun Lintian hurriedly retracted the spear back and used his other hand to touch the position that was supposed to have the invisible barrier. However, there was actually nothing in that place. 

Seeing this, Yun Lintian brought the crow demon's corpse to the front again and saw it obviously disappear like it was before. This gave Yun Lintian a general understanding. To enter the place, one must have Abyssal Energy on their body.

Yun Lintian pulled the crow demon's corpse back and took its abyssal profound beast core out. He tossed the corpse away and held the core in his hand before trying to walk into the invisible barrier. 

The moment he stepped forward, Yun Lintian could clearly feel a soft wall in front of him. This proved his idea was correct. Using Abyssal Profound Beast Core resulted in the same as possessing Abyssal Energy.