The dripping sound was heard after walking about twenty steps inside. They were walking clockwise, but just before they entered another door at the end, Zhang Yufei heard the dripping sound again, and it was less than ten steps forward.
So, it seems, after entering the main entrance of the cave, there is a small door about thirty steps in. This door must be a hidden mechanism, just not very loud.
Zhang Yufei vaguely heard a clang but couldn't tell if it was the sound of the door opening or a mechanism.
Finally, Zhang Yufei's veil was lifted. This was what the Earth Dragon called the factory. Looking at the massive project, Zhang Yufei was dumbfounded.
Hu Fei, seeing Zhang Yufei's astonished expression, laughed and walked over, saying, "Haha, sorry about covering you just now. This is our factory. Isn't it grand? Well, let us take you for a tour."
"Alright."
Zhang Yufei immediately snapped out of it, put on gloves and shoe covers, and started touring with Hu Fei and the others.
