The basement of the Red Stone Hotel wasn't extensive—nothing more than a warehouse, really.
Even though Claus did his best to lower the criteria for combat personnel, a large number of non-combatants were still filtered out.
Thousands of people were crammed into the basement. Ignoring sanitary conditions for a moment, the density of the crowd now facilitated the massacre by the two duplicants.
A simple Sonic Sword Technique (Oscillation) could instantly kill dozens, even hundreds, of people, not to mention the attacks from Qin Tian's duplicant, for whom distance was irrelevant. All Qin Tian's duplicant did was simply wave his hand; each gesture inevitably snuffed out one or, indeed, many vibrant lives!
