C156 Underground Rock Layer and Yang Rong's

"Knock knock …" He nudged it with the tip of his foot and heard a rumbling sound. It was accompanied by a certain echo, and he could also feel a slight tremble.

"So that's how it is. Like I said, important people cannot brazenly show themselves. Heh, Yang Rong's brain is truly not ordinary."

Ye Donghan had met many smart guys before