Jian Wushuang was not afraid, he was just scared.
Jian Wushuang knew the origin of Eternal Dark Prison from Lord Wu. He knew what kind of place Eternal Dark Prison was.
Think about it, countless prisoners were locked in there and never saw the light of day. Many years had passed. Even if the prisoners were not crazy, they would have become crazy. Moreover, those prisoners were all very strong, even the weakest one on the first level was an expert at the peak of the second level. Any one of them was enough to make him treat them seriously.
However, what Lord Wu said made sense. He could not find a match in this Star Field, but he could not leave this Star Field for the time being. If he wanted to continue to improve his strength and challenge new experts…Eternal Dark Prison was indeed a good choice.