Di Jiu came out because Huan Mingzi had asked him to. Di Jiu had thought that since he was already at the peak fourth-stage True Form Realm, he should be able to reach the sixth stage without any issues if he could just cultivate in seclusion for another two to three years. Because he thought so, he had been very relaxed while he had been in seclusion earlier. He had spent two to three months practicing alchemy in order to become a grade-nine Elixir King. At the same time, he had turned the stalk of Ice Vine into 12 True Vine Elixirs.
He had spent this time practicing alchemy because, firstly, he wanted to take time off to collect his thoughts right after reaching the peak fourth-stage True Form Realm by cultivating at the Five Continent Dao Pagoda. Secondly, he wanted to help Geng Ji refine the Ice Vine Elixir before he went to the True Dominion.