A man stood at the center of a pristine white cubic room.

His rolled-up sleeves revealed solid muscles, and a bead of sweat trickled down from his well-groomed black hair onto his forehead.

As he took a deep breath, tensing his muscles, a woman’s voice echoed throughout the room.

[Evasion rate: 98.5%. Passed. Would you like to proceed to the 10th stage test?]

"Start."

Beep—

Whizz! Whizz! Whizz!

At the sound of his voice, an alert tone rang out, and metallic spheres began shooting out at terrifying speeds from the previously blank white walls.

"Hoo."

The man held his breath, …