Noah didn't take that decision lightly. He had already considered that the Crystal City and its allies would do everything in their power to hunt him down.
Yet, that partially worked in his favor. Noah didn't want his return into the human domain to mark the beginning of a peaceful period. He needed struggles to continue growing.
Moreover, Noah had finally touched the eighth rank. It was time to step up his game and start messing with organizations. It was impossible to seize resources that mattered at his new level without affecting other large forces.
Noah also was in desperate need of energy. His unstable substance was almost about to run out, and the weakness that he felt affected the empowerment given by his ambition.
The insane might expressed by the Demonic Form even worsened his condition. The ambition had covered most of the expenses of his superior power, but his time was running out.