If this were a game, then "deliver a letter to General Gao Ao's camp and request treatment for him" would probably be Aluba's mission to join the heavenly troops' faction.
However, according to Li Fan's analysis, the chance that the immortal they sought this time was the father of those two idiotic horses and the abandoned disciple of Penglai, Ling Chengdao, was actually not high. Given the time and place, it was more likely that they would meet another mission target, the traitor of Penglai, Cheng Chengzhi.
