That being the case, they likely didn't see Feng Xin as a threat, hence why the seal hadn't reacted or triggered any strangeness from Haishi. A puny late-stage core formation expert, even a talented one, was nothing before a soul formation expert, not even against a mere wisp of their soul or spiritual will.
Yang Qing was confident of this. He, Dai Chen, Zhang Qingge, and the others had nearly died to the spiritual will of a soul formation expert and had been utterly helpless against it. If not for the timely intervention of one of the vice presidents and the chief inquisitor, they would have perished.
Yang Qing still had nightmares about that day. Fortunately, he had Old Fiend Lei's nightmares to counteract them.
As such, he strongly felt the reason the seal reacted had nothing to do with his realm or his prodigious abilities. It likely had more to do with Haishi's new environment.