Chu Feng touched the stone wall and asked curiously, "What kind of ore is this, and why is it blue?"
Anna explained, "The underground here for thousands of miles around is made of this stone, which provides light and heat that allows us to survive below the caves."
Nightingale said, "It has always been like this down here; we have no idea what this stone actually is."
"See, you completely lack a scientific spirit."
Chu Feng criticized before punching the wall, hoping to break off a whole rock to study it further.
The punch brought with it wind, and the area shook with a rumble.
The density of this rock was surprisingly high; Chu Feng's punches could pulverize the rocks outside.
But here, even using thirty percent of his strength, he couldn't budge it.
"I still don't believe it."
Feeling frustrated, Chu Feng reached out his hand towards Ji Wanyu and said, "Princess, lend me your Emperor Yu's Sword."
Ji Wanyu smiled and handed it to him.
