Normally, the Entrapment Formation would not be put into use because it was not to trap enemies, but people on their own side.
Basically, enemies could not enter the Demon-slaying Hall. If they could get in, then the Entrapment Formation would be pointless. In history, the Entrapment Formation was used on three occasions and they were all to trap traitors of the human race.
As before, only Li Shang and nine patriarchs went outside the hall. The others must not leave a step. In case Jiang Tianshun and Great Grandfather Three would go and provide Lu Li with information, Ji Zhantian had put them under surveillance.
Great Grandfather Three was anxious. Fire was going to burst out from his eyes, but he could not do anything out of impulse or else Ji Zhantian would have him killed in the name of greater interest. Great Patriarch Three would not only lose his life but also leave behind ill fame.
