77 Uninvited guests

After walking for a while, they arrived at the mining area. Alexander brushed away the loose soil on the ground with his hand, revealing the rock layer beneath. 

He crouched down to examine it and found that this rock layer was indeed very unusual. Its shape and color were different from the norm, and there was even a strange spiritual energy protecting it.

It seemed that someone had discovered this mining area earlier but lacked the ability or convenience to mine it. They had therefore arranged a barrier made of spiritual energy in an attempt to prevent others from exploiting the mining area.

Seeing Alexander remain silent, Smith became impatient, his face filled with frustration. 

He explained to Alexander, "We've tried everything, even armor-piercing missiles, but nothing can break through this rock layer. It's really strange."