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Tian Xun summoned a pet similar to a Devil Fish, and the four of them rode downstream on the back of the Devil Fish.
The black underground river widened increasingly, and as the river expanded, Tian Xun's Devil Fish pet also grew in size, making the space more and more spacious.
Lin Shen placed Ye Xing and Ye Kong on the back of the fish, standing shoulder to shoulder with Tian Xun, checking out their surroundings.
The humanoid pet was holding the Lamp of Life and Death, flying ahead of them, its light illuminating the nearby area.
However, as the river widened, the light from the Lamp of Life and Death could no longer reach the riverbanks, and all around them were turbulent black waves.
Lin Shen took out the Nightglow Flower, hoping to see farther, but the result was the same; he couldn't see anything and had no idea how wide the blackwater river actually was.
The river's waves grew fiercer and even began to swell into waves, as if they were ocean waves.