Lin Mu and the rest of the Hei Corps were currently walking on the stairs that led to the entrance of the safe house. The stairs were dark, but the lamp that Hei Bao was holding helped to dispel the darkness, allowing them to watch their steps.
"We must be at least fifty meters deep underground," Xukong spoke.
"We are? How much time must've been needed to build this passage!" Lin Mu internally exclaimed.
"Use your spirit sense to check the walls, I'm finding them to be a little strange," Xukong spoke.
"Yes, Senior." Lin Mu responded.
Lin Mu then used his spirit sense to probe the walls and found out the walls were a little hollow and there was an empty pocket behind the plain wall. The brick walls of the passage seemed to have been added later to make it look much more smoother. The actual walls of the passage were hidden behind these walls and seemed to be made out of completely solid rocks.