Xue Wuheng became desperate. He attacked a divine immortal and absorbed their power. He never thought that Han Jun was beyond his reach. He was easily defeated and ended up here.
As to how he could plot seamlessly and leave a realm said to be impossible to escape. The primordial power he had absorbed from the divine immortals during the war meant he had acquired certain special abilities.
Abilities that couldn't be contained by the seal. After thousands of years of repairing his body, a part of his soul could leave the realm. This was how he had been able to meet the Demon Lord and Peng Xiu. It caused him excruciating pain, but he was more than determined. He finally got his wish. Han Jun came to see him.
He had saved Han Jun, and that debt needed to be repaid. He would take Han Xin's soul. Together, they could stay in this realm, and that way, Han Jun would always come to see him. That was the plan.
But Xue Wuheng didn't count on Xiang Yu screwing over his plan.
***
