In the dark underground world, a flying shuttle was moving quickly.
This flying shuttle was almost silent, even when traveling at a speed of over 500 kilometers per hour, it did not produce noticeable noise.
The underground world was vast, like an abyss, and in the vast darkness, this flying device was like a firefly, illuminating a small part of its vicinity.
But it was only a small part.
"Yawn..." Keke had grown tired of the monotonous scenery outside the window, her small body already curled up in Xu Xin's arms, yawning and beginning to feel sleepy.
"Say, if we keep the lights on all the time, won't we be easily discovered?" Xu Xin asked the man.
"Around here, we don't need to worry about that for now, but after advancing another 200 kilometers, we'll need to turn off the searchlights." The man replied.
"Then in the darkness..."
