They had the strongest fighting force and the ultimate weapon, but they still lacked the most crucial piece-intelligence.
The Infinity Castle was Muzan Kibutsuji's last fortress and his greatest home-field advantage. That otherworldly stronghold, constructed through Nakime's Blood Demon Art, had inverted spaces and endless transformations. Once dragged inside, the Demon Slayer Corps' swordsmen would be separated, isolated, and ultimately defeated one by one.
This was a problem the Demon Slayer Corps had been unable to solve for centuries.
But before Uesugi Sasuke, who possessed the Rinnegan, it was no problem at all.
Deep beneath the Demon Slayer Corps Headquarters stood a prison specifically used to hold "captives." Of course, the demons imprisoned here were usually unlucky wretches who had been abandoned by Muzan, were weak, but happened to know a few secrets.
When Sasuke arrived, the few Kakushi members on guard immediately bowed respectfully. Their eyes were filled with awe and a trace of... fear as they looked at him.
Since Sasuke had become Commander-in-Chief, his training methods and way of doing things had established an authority among the ordinary members more terrifying than even the Demon King's.
"Bring him out." Sasuke pointed at a demon curled up in a corner of a cell, trembling.
This demon had once been responsible for delivering food-humans-to the Infinity Castle. Muzan had abandoned him after a mistake, and the Demon Slayer Corps had later captured him.
"Yes, sir!"
The members immediately dragged the demon out and pinned him down before Sasuke.
"L-Lord Thunder Hashira... spare me! I've told you everything I know! I really have!" The demon was scared out of his wits, begging incoherently for mercy.
Sasuke could not be bothered to waste words on him.
He crouched down, his cold Rinnegan staring straight into the demon's fear-filled eyes.
"Look into