Batman decided he could not hold back anymore. Honestly, it felt awful, like he was facing the opposite version of himself.
He wanted to suppress the other man somehow. Otherwise, his self-imposed no-killing rule would start to waver.
As it happened, The Grim Knight felt the same way. No other reason—he simply thought this guy was stupid, with no discrimination intended.
The Grim Knight had been through too much and lost too much. Even Alfred was going to leave him.
So The Grim Knight planted a miniature bomb in Alfred's head to control him.
Just as Batman had said, The Grim Knight was nearly insane—the incurable kind.
There was only a slight deviation.
It made The Grim Knight feel that he could put off going insane a little longer.
Batman threw a punch. The Grim Knight's raised assault rifle was kicked away, and the punch landed squarely.
The Grim Knight took the blow head-on without holding back. He spun around and kicked Batman flying.
The corridor was not very wide.
Almost the instant Batman came to a stop, his keen instincts and reflexes made him raise an arm to shield his head.
He avoided being struck by The Grim Knight's high kick.
Neither of them was much for talking. After exchanging a glance, they launched into another fight. Unlike Batman, The Grim Knight had never traveled the world or received Ra's al Ghul's guidance.
To quell his own fury, he had honed his body since childhood—beating trees, fighting people, learning everything. He was a thorough pragmatist.
Every move he used in a fight was meant to kill with a single blow.
Fortunately, Batman's martial arts were no less formidable. The two were evenly matched, but it felt even more like looking into a mirror.
With a boom, they traded punches,