Infinity Castle.
This was the spacetime domain controlled by Nakime, the Biwa Demon. The Serpent Hashira had once described her as, "Her Blood Demon Art isn't all that lethal, but it's first-rate when it comes to being annoying and difficult to deal with."
Indeed, Infinity Castle had little offensive capability. This unique space contained no hidden weapons, such as traps or concealed projectiles. Nakime could only manipulate its terrain, but that alone made her a formidable nuisance.
Chinatsu hadn't heard Muzan call out "Nakime" in his mind, but if she had, she would definitely have remarked on how much it reminded her of Illyasviel shouting "Berserker!" in Fate.
Uh... it also felt a little like Clara shouting, "Help me, Mr. Svarog!" in Honkai: Star Rail.
He was desperately trying to save his own skin, yet his expression remained utterly self-righteous.
"What pathetic little tricks! Did you really think you could ambush me? That you'd driven me into a corner? What a joke! I am the King of Demons! All of you can go to hell!!!" Muzan shouted arrogantly, his face rigid.
But the moment he finished speaking, he fled in panic with his battered body. The sight of him running away stood in jarring contrast to his grand declaration.
"Don't run, Muzan!!!"
Everyone roared at Muzan as he turned and fled after delivering his threat. But shouting at someone not to run hardly meant they would stop, especially when that someone was a coward of Muzan's caliber.
Under everyone's furious stares, Muzan dashed out of sight in a blur. With Nakime deliberately changing the terrain to conceal his location, he bought himself plenty of time to regenerate his body and break down the poison within him.
Muzan panted heavily. In his fury, enormous masses of flesh sprouted all over him,