The Darkness Devil is so powerful because humanity has feared the dark since the dawn of time—it is the most primal of all fears, which is why it bears the title of "Primal Fear"!
It is well-known that the deeper the fear humanity (and other devils) holds for a particular object or concept, the stronger the corresponding devil becomes. Primal fears are, naturally, the strongest of all. Examples include Darkness and Falling; these are the known Primal Devils from the original lore. Death is a Primal Devil, as even her sisters—Control and Famine, who are also among the Four Horsemen of the Apocalypse—hold the Death Devil in extremely high regard. In the source material, the Famine Devil believes that only a War Devil at full power stands a chance of preventing the Nostradamus prophecy—the advent of the Death Devil—while the Chainsaw Man Church pins its hopes on a fully-powered Chainsaw Man.
However, the sense of dread projected by both Falling and Death pales in comparison to that of the Darkness Devil.
"This guy... I don't think even the Fourth Form Susanoo can hold up against this..."
Chiya stood within the head of the Crow Tengu Susanoo, observing the full silhouette of the Darkness Devil from a distance. Its appearance resembled a bipedal pterosaur; its strange head bore a pair of horns, and its body was a grotesque amalgam of human torsos. Four human heads and twisted limbs formed the torso of the Darkness Devil, each head bearing a different expression. Its legs were comprised of human torsos, and it was draped in a massive, dark cloak.
"I told you to run! Why won't you listen!"
The Rage Devil within Chiya was screaming in utter panic. Although she had long since lost her memories of Hell from before her reincarnation, the aura of extreme danger and the manifestation of darkness allowed her to recognize this as the Primal Darkness Devil—a being that even other devils feared to the core!
Chiya had no time to respond to the Rage Devil, his eyes locked onto the Darkness Devil in the distance.
[Ding! Host has unlocked the achievement "First Encounter with the Darkness Devil," gaining 10 Attribute Points!]
Suddenly!
"Ribbit!"
From somewhere, a frog croaked, and the Darkness Devil instantly teleported from the distance to stand directly before the Susanoo.
Chiya could barely track the Darkness Devil's trajectory, let alone its actual attack motions.
CRACK!
In the blink of an eye, the Susanoo, reinforced by the Crow Tengu armor, had already sustained numerous fractures. Even the ultimate defense of the Fourth Form Susanoo could barely withstand a single blow from the Darkness Devil. It was estimated that one or two more hits would shatter the Susanoo completely.
[Available Attribute Points: 135 (Total accumulated: 991)] [Ding! Allocation complete: Vitality +135] [Strength: 160] [Speed: 160] [Vitality: 684 (+5)]
Chiya decisively poured all his attribute points into "Vitality" and donned the "White Mask" attire to maximize his Vitality stat as much as possible. Currently, he could sustain the consumption of the Fourth Form Susanoo, but the armor itself couldn't handle the Darkness Devil's onslaught.
He was also getting a bit carried away; he wanted to see if the Complete Body: Susanoo could actually trade blows with the Darkness Devil. Provided he could ensure his own survival, he wanted to go all out in a grand battle against this entity!
Meanwhile, far outside the domain of darkness, a humanoid devil stood atop a mountain peak. Its eyes, bearing a pattern resembling the Rinnegan, gazed out toward the direction of the dark domain.
This humanoid devil appeared in the likeness of a young human girl. Her beautiful face remained void of emotion, accented by a few beauty marks, and she wore earrings shaped like scales—the weight of which seemed to cause her head to tilt slightly to the left.
This was none other than one of the Four Horsemen of the Apocalypse: the Famine Devil!
"The one fighting the Darkness Devil is... a human? Or a devil?" The Famine Devil murmured, her expression unchanged. "Although there is a devil's aura, it should be a human. A human capable of coming to Hell and battling the Darkness Devil... interesting..."
The Famine Devil remained outside the Darkness Devil's domain, observing the situation from the edge. She held no grudge against the Darkness Devil, and currently, the Darkness Devil had no interest in minding her presence outside its territory.
Just then, the Famine Devil's chin tilted slightly higher. The cyan-blue giant in the distance had grown even larger; its stature had doubled again to roughly 200 meters—nearly the height of the very mountain peak she stood upon.
This was Otonashi Chiya's Complete Body Susanoo!
Inheriting the Crow Tengu armor from the Fourth Form, the armor now covered his entire body more completely, and a pair of wings capable of blotting out the sun sprouted from his back. In his hands, he gripped the ultimate form of the Sword of Rage.
At that moment, the Darkness Devil raised a hand, pointing a finger directly at Chiya, who was positioned in the head of the Susanoo.
The instant the Darkness Devil began the motion to raise its hand, Chiya perceived that it was about to unleash its ability. He struck first, swinging his sword before the Darkness Devil could activate its power. A blade wave, nearly as massive as the Complete Body Susanoo itself, instantly engulfed the Darkness Devil.
Not only that, but the blade wave went on to obliterate everything for tens of thousands of meters in front of it!
"BOOM—!!!"
The earth-shattering roar of the terrifying blade wave thundered through the air. The Famine Devil watched with her own eyes as the wave barreled toward her! Her pupils constricted, and her figure instantly vanished from the mountain peak, reappearing a moment later on the grass far in the distance.
"Oh..." The Famine Devil let out a flat, emotionless gasp. "That was close. I was almost caught in the crossfire..."
She looked back at the small hill she had occupied just seconds ago; it had been sliced cleanly in half vertically. Had she not dodged, her fate would likely have been no better. It was only because of her distance that she had time to react. She surmised that if she had been standing in the Darkness Devil's position, the consequences would have been either death or permanent maiming.
"Are there already humans this strong in the mortal world...?"
The Famine Devil's gaze returned to the Susanoo, shock rippling through her. In her view, the human still couldn't defeat the Darkness Devil, as the latter was effectively immortal while within its domain of darkness. However, she was stunned by a destructive power capable of obliterating nearly everything in its path. If the Darkness Devil were outside its domain, the outcome might be different—but such a scenario was impossible; even the Darkness Devil wouldn't be stupid enough to leave its invincible realm.
At this very moment, Chiya could see that the Darkness Devil had been heavily damaged by the blade wave—the four heads on its alien torso were spraying blood—but they instantly regenerated as if nothing had happened. Such was the power of the Darkness Devil within its own domain.
"Truly immortal, I see. Then let's try another strike..."
Chiya knew well that he couldn't defeat the Darkness Devil, but having come this far, he didn't want to stop halfway; it would feel far too unsatisfying. As his intent flared, he channeled the warping spatial power of "Kamui" into the blade of the Sword of Rage...