After an unknown period of time.
Huo Qiyun asked in the darkness, "Is it still vibrating?"
"Yeah."
...
"And now?"
"… Same."
...
"Can we do it now?"
"… Not yet."
...
It was unknown how much time had passed in the darkness. It might have been an hour or a day.
Lin Ran finally perked up again. "Get up and get to work!"
Huo Qiyun sighed and stood up. After sitting for so long, his legs were numb!
After checking the thickness of the stone walls, Huo Qiyun shook his head at Lin Ran. "I can't do it. These stone walls are more than 300 feet thick. The sword intent here is too strong. I can't break it."
Lin Ran nodded and pressed on a stone wall. He shook his head and pressed on another stone wall.
A moment later, Lin Ran finally retracted his hand. Huo Qiyun quickly asked, "How is it?"
Lin Ran replied with a strange expression, "A thousand feet."