Entering the core fortress of the Celestial City, Lu Yu stood on the first level, observing the surroundings.
This place resembled an inverted tower, with each level spiraling down like threads on a screw.
He looked up, seeing the sky outside through the open ceiling, pitch black.
Here, Lu Yu could clearly see the source of Celestial City's barrier. At the top of the core fortress, a beam of light shot into the sky.
This beam of light was invisible from the outside and could only be seen within the core fortress. It supported the entire defense of the Celestial City.
After watching the defensive barrier above for a while, Lu Yu felt relieved when he noticed the beam generating the defensive layer hardly changed, no matter how the bizarre creatures outside attacked.
This indicated that, at least in the short term, the Celestial City wouldn't be breached.
"Lu Yu, come here quick," Su Peng shouted loudly to Lu Yu.
