Athan saw the man taking out a stone, and in that instant, he used Gaze of Void to incapacitate him.
The man's mind went blank as his soul was suppressed, and he couldn't do anything.
Athan also changed his void frame to Extremity Drifter and swooped beside the man at the highest speed possible by Athan and cut the hand of that of man that held that stone.
Athan did that because he felt some space fluctuation, and he didn't want this man to escape.
After Athan cut off the man's hand, a golden brilliance shot out from the man's body as he regained consciousness.
Athan didn't want to kill this man quickly; that's why he didn't use the full power of his Gaze of Void and only used it to incapacitate him to prevent his escape.
"Y-you...stop."
The man now looked at Athan fearfully as his previous arrogance was gone.