Chen Guan was also making preparations. The alliance between the Gong Family and the Demon King City against him was a big problem, but it was also a great opportunity.
He had been worrying about finding an excuse to eliminate the Gong Family's influence in the Pengxuan Grotto Heaven, and to take over their population and territory. Now, with this situation, he had a legitimate reason to take action against the Gong Family.
The key issue was that the Purple Sun City wasn't financially strong at the moment, and might not win the battle against the Gong Family and the Demon King City.
Chen Guan thought he needed to make more preparations. Otherwise, if Purple Sun City suffered too significant a loss in this battle, it might not have the strength to take over the Gong Family's territory, and it could even be taken advantage of by other families and forces.
Moreover, after taking over the Gong Family's territory, he would need people to manage it, requiring additional manpower.
