The Huakai Sect, and Wu Xi, who went missing, as everyone had guessed, really had 'luckily' entered the underground palace. But, it was through another entrance and not the entrance where the others had camped. Or else, they would have all already met each other.
Their entrance to the underground palace was all thanks, again, to Shan Lu who stupidly followed another impostor inside the entrance. By the time the others had managed to pull him back, mysteriously, the entrance behind them closed and they were trapped inside without properly preparing themselves against whatever would attack them when they went inside.
"Shan-shixiongβ¦" Guo Cheng speechlessly looked at Shan Lu.