It was time to leave Castle of Black Iron.
If Zhang Tie could solve all the problems in Castle of Black Iron and could promote all the way to immortal emperor successfully at the highest speed before returning to Taixia Country, it was okay for him to stay inside Castle of Black Iron. Pitifully, even if he could absorb four elements in Castle of Black Iron, it would also take him a long period of time to promote to a sage-level knight, not to mention an immortal emperor.
Zhang Tie had been used to utilizing Purgatory Samsara Method for cultivation and had already jettisoned the stereotyped cultivation method step as the stereotyped way of cultivation was consuming too much time.