Zero put away the special sensor pistol that he used to simulate a battle. In his eyes, the battlefield was gradually fading. That was the reason why the background wall was closing.

When the area around him was completely dark, another spotlight lit up above his head, and an area roughly the same size as a football field, with floor and walls embedded with metal plates, appeared in front of his eyes. This was a simulation site for actual combat. Through a holographic projection ...