Cain had previously been under the impression that those who had been left within the hall of the main building had all become devil food because they were negligent of their surroundings, and had been caught unawares by the devil. But now, he figured there was more to it than meets the eye.
He had been told by the system that they had been turned into zombies by the {Miasma Devil}, but he didn't ask how it happened.
'System, how did they all turn into zombies?' When Cain asked, the system automatically knew who and what incident Cain was referring to.