Only by thoroughly merging the fragment of the Immortal Realm and refining the aura of the Heavenly Source into her own immortal energy, could Shen Ruyan possibly resist the power of the Celestial Immortal.
Otherwise, this blow would completely reverse the situation, allowing the Hidden Immortal Sect to claim the final victory in this battle and become the last ones standing, with Xiandao as the victor.
For Jiang Chengxuan, it might not matter. He simply viewed these people as a chance for Shen Ruyan to gain experience. Even if they were allowed to leave, it wouldn't affect anything.
With Jiang Chengxuan's current strength, these people could do nothing, whether within this secret realm or in the Xuanyuan Immortal Domain.
However, Shen Ruyan did not want everything to end like this. She did not want to fail, nor did she want to be a burden to Jiang Chengxuan.
She didn't want to hide behind Jiang Chengxuan forever and do nothing.