This underground world is vast, even with the Netherworld Demon Pupil Star, Lin Feng is unable to see its boundaries.
His gaze swept over the underground world, it has mountains, rivers, and many oddly-shaped black plants and trees.
However, this underground world is not entirely dark; instead, visibility is remarkably good.
A thousand zhang overhead lies endless rock walls, embedded with luminous pearls every hundred zhang, illuminating the underground world like daylight.
With the Netherworld Demon Pupil Star, Lin Feng carefully observed but found no trace of the Yellow Springs Demon Sect's people.
After a little pause, Lin Feng's figure moved and flew into the distance.
He did not fly too high to avoid detection by the Yellow Springs Demon Sect, merely flying low and exploring as he advanced.
"Hmm?"
After flying for over a thousand li, Lin Feng suddenly stopped, then flashed and hid beneath a giant flower behind a low hill.
