Chapter 240: What is the strongest? Let me show you

"That's the enemy's ultimate ninjutsu!"
The reason why Xiao Zheng was so shocked was that, in the secret method, ninjas were the dominant ones on the battlefield!
On the battlefield, it was pitch dark, without any light or shadow. Even if one wanted to use some secret method to detect any sound, it would be in vain!
There, it was like entering another silent, lightless, shadowless and odorless space!
However, the person who uses the secret method can see all of this clearly!
Therefore,...