Xu Huo and the living specimen had been separated for less than two hours. When he entered the rest room just now, he discovered that the Alien locked in the cage was already dead. Although dead, one could still hear "heartbeat" and "breathing"; using a Prop to fake the state of being "alive" wasn't difficult, so it could deceive Shangguan Xi and the others who had been inseparably close by.
Besides the five people including Shangguan Xi who could come into close contact with the living specimen, there were also personnel from this training base, as well as Gao Xiaoyan and a few others who had approached after they had separated.
The fact that the living specimen had been sent here, only to be killed at the last moment, superficially seemed to be hindering their progress through the game. In reality, regardless of who made the move, preventing their game progression couldn't be the true intention; hence, the issue naturally returned to the living specimen itself.