A certain crossover anime's nuclear-powered sword immortal

Its body alone was 120 meters long, and its outstretched wings shrouded the city in darkness. Then, as the black dragon opened its massive mouth, the black mist it spewed out spread throughout the entire city. Immediately afterwards, six enormous venomous snakes, each 20 meters long, began to wreak havoc.

Erica, who had already summoned her beloved sword "Reinhardt" to fight the venomous snakes, suddenly saw the surrounding space undergo a dramatic change.

Then, she saw a figure running at an extremely fast speed, and then suddenly leaping into the sky. Judging from the momentum, it seemed to be heading straight for the black dragon that was coiled in the sky.

In that instant, a blue lightning bolt, as powerful as thunder, shattered the sky, and a deafening explosion pulverized the earth. The imposing black dragon in the sky vanished, and the venomous snakes that had been ravaging the city's civilians also disappeared, as if they had never existed.

This incredible scene filled Erica's pale purple eyes with confusion and surprise; she couldn't quite understand the current situation.

It was as if a 'disobedient god' had appeared, plunging the entire city into terror and chaos, yet the figure vanished with its appearance, leaving everyone puzzled.

However, since those things have all disappeared, it seems that no one will be harmed as a result, which is a good thing.

Erica stayed where she was for a while, and after finding nothing amiss, she left to contact the local magic society to clean up the mess.

Erica probably never imagined that at this very moment, her friend Liliana was witnessing an epic battle.

……

Hearing the melodious laughter, like the tinkling of silver bells, Shirou slowly opened his eyes, and a beautiful face was immediately reflected in his brown eyes.

It was a face that looked slightly childish and cute, like a porcelain doll, but strangely, although the face looked no different from that of a teenage girl, it gave Shirou a special kind of bewitching charm.

"He doesn't seem to be purely human. There's something about him that I don't understand... But he is indeed an excellent child, and he even defeated that arrogant black dragon."

"However, you didn't die even after going through a battle of that scale... In that case, there's no need to revive you."

The girl's voice seemed to carry a hint of surprise and relief, as if she was pleased that Shirou was very strong.

As the girl's soft voice echoed in Shirou's ears, he could feel that he was lying flat on his back.

And his slightly fatigued spirit, which had been somewhat exhausted after the intense battle, was now recovering at an extremely fast pace.

Feeling the softness behind his head and recalling the girl's position in his eyes, Shirou immediately realized that he was lying on the girl's lap.

'Having a lap pillow after a big battle is actually quite nice.'

With this little thought in mind, Shirou began to scrutinize the girl in his eyes.

Judging from her cute baby face and slender figure, she looks like a girl around ten years old. Although her face looks like that of a young girl, her cute face paired with her emerald-like eyes gives her a bewitching beauty.

Her slender body was dressed in a thin white dress, and she was very petite, suggesting that she must have been very light-footed.

Shirou actually saw

The girl guessed her identity at first glance.

Pandora—the goddess who manages the reincarnation rituals of god-slayers. Anyone who fights against a 'disobedient god' and ultimately defeats it will arrive in the 'realm of life and death.' Then, Pandora, through the reincarnation ritual, will transfer the power of the defeated 'disobedient god' and a body comparable to that 'disobedient god' as a reward to the human who defeated the 'disobedient god,' transforming them into a demon king, that is—a god-slayer!

Even so, all the "godslayers" who came to the "realm of life and immortality" and underwent the Pandora Reincarnation Technique have, without exception, lost their memories of the "realm of life and immortality".

This is because of the unique nature of the reincarnation technique, which causes those 'godslayers' to forget their memories of the 'realm of life and death' after being resurrected.

Although Shirou knew the identity of the goddess in front of him, he felt it was better not to take the initiative to recognize her to avoid unnecessary trouble.

If Pandora doesn't perform the reincarnation ritual on me because of unpredictable troubles, so that I can acquire the powers of the black dragon Nidhogg and enhance my body, then all my previous efforts would have been in vain.

With this thought in mind, Shirou immediately put on his Oscar-worthy acting skills, and a look of confusion appeared on his face.

"Who are you?"

Hearing Shirou's question with a puzzled look, Pandora blushed with excitement, reached out and cupped Shirou's cheeks, and answered softly.

“My name is Pandora. You are currently in the ‘Boundary Between Life and Immortality.’ You killed a god, which alerted the ritual here, and your spirit was directly transported here. Now you are my seventh ‘son’~ Come on, call me Mommy~!”

"..."

Shirou looked at the goddess who was looking at him with great anticipation, speechless.

Upon seeing it with his own eyes, Shirou realized that no matter how he looked at it, this goddess lacked the majesty of a goddess, and instead seemed as lively as a child with a quirky personality.

However, in order to obtain the power of the 'disobedient god', Shirou decided to grant her this small request.

"'Mom'...why did you bring me here?"

Upon hearing the name Shirou uttered, the girl's face lit up with excitement, and even her emerald green eyes seemed to glow.

"That's wonderful! You're the first child to call me 'Mom'!"

Upon understanding Pandora's words, Shirou's expression froze.

Chapter Nine: Divine Authority in Hand!

Shirou naturally understood the meaning behind Pandora's words.

In other words, the previous six 'godslayers' never addressed the goddess in front of them as 'mother'.

Even so, they still received divine power.

Shirou immediately felt very annoyed.

Did I actually lose or gain something?

At this moment, Pandora seemed to notice the somewhat speechless expression on Shirou's face.

Suddenly, she swayed slightly, leaned down, and spoke to Shirou.

"Don't be upset~ My seventh child, having such a lovely goddess who isn't even related to you by blood as your 'godmother' is no loss at all, you could even say you've gained something!"

She spoke with such conviction that Shirou felt somewhat helpless. He decided not to continue arguing with this goddess, whose thought process seemed rather peculiar, and instead asked her directly.

"In short, I should now be qualified to acquire divine power, right?"

Upon hearing Shirou's words, Pandora's face immediately broke into a cute smile.

Then, she looked at Shirou with 'loving' eyes and said.

“Yes, since you’re so eager, I’ll grant you the powers of ‘Black Dragon’ Nidhogg right now.”

"Okay." Shirou replied immediately, he was already a little impatient, but he still managed to maintain his composure.

Next, Pandora leaned down and pressed her cute and beautiful face close to Shirou's face, and said.

"Normally, reincarnation techniques wouldn't go this far, but as the first good child to call me 'Mom,' I'll give you a reward~"

Upon hearing Pandora's words, Shirou was immediately puzzled. As he pondered what the 'reward' Pandora was referring to, the fragrant breeze that wafted towards him made his pupils shrink.

Meanwhile, Shirou felt his body heating up, as comfortable as soaking in a hot spring. In this incredibly comfortable state, Shirou gradually became sleepy, and the world before his eyes began to blur.

As Shirou fell into a deep sleep, due to the power of the Reincarnation Technique, in that 'realm of life and immortality,' the power of divine authority fell into Shirou's body like golden lightning, and at the same time, Shirou's body began to faintly radiate divine light.

Like a dream, Shirou, who was fast asleep, saw a scene that seemed like an epic.

That was a piercing

The trunk of a tree pierces through heaven and earth, making everything in the world seem incredibly small, and that enormous trunk separates the mortal realm from the heavenly realm, dividing them into two regions.

Just like the gods on earth, the gods in the heavens are constantly at war because they hold different opinions.

But in the mortal realm, unknown to anyone, at the base of the World Tree, a giant black dragon was coiled, constantly gnawing at the three roots of the World Tree.

The venomous snakes that followed the black dragon in devouring the World Tree were quite different from snakes. They had long, prominent horns on their heads and four legs on their bodies. Shirou clearly remembered that the creatures were called 'Jiao'.

Then, after the black dragon devoured the three tree roots, the heavens began to shake, endless twilight shone, and the end of the world arrived.

……

As if traversing a dream spanning ten thousand years, Shirou's consciousness gradually returned to the real world.

When Shirou opened his eyes, the first thing he saw was the girl's beautiful face, which was as lovely as a fairy.

"Great, you're finally awake!"

Seeing Shirou open his eyes, Liliana immediately showed a relieved expression, and then looked at Shirou with concern.

"How are you feeling? Are you feeling unwell? I can cast a healing spell on you, ah... but I've never used magic on a demon lord before, I don't know if it will work..."

The girl spoke faster and faster, and judging from her anxious expression, she seemed even more concerned about Shirou's health than he was about him.

"How long have I slept?"

As Shirou felt the soft legs behind his head, he marveled at how destined he was to have a lap pillow today.

"Hmm...it's been about half an hour."

Liliana quickly replied.

Upon hearing her answer, Shirou immediately sat up, and after a moment's recollection, he discovered that he had actually retained the memories of that 'boundary between life and death'.

The adorable doll-like face of the goddess Pandora seemed vividly before my eyes, completely unforgotten.

Shirou smacked his lips, as if savoring the last trace of sweetness and refreshing fragrance in the 'realm of life and immortality'.

"Was it because of Pandora's help, or because of the system, that I was able to retain my memories...?"

Shirou had this question in his mind for a moment, but he quickly put it out of his mind.

Because he could feel that after undergoing the reincarnation ritual performed by Pandora in the 'realm of life and death', his combat power had increased significantly.

Furthermore, since Shirou's original body had already reached a level where he could fight against 'disobedient gods', this enhancement has allowed him to reach a level that none of the previous 'godslayers' had been able to achieve.

Furthermore, Shirou also gained the divine power of Nidhogg, the 'disobedient god' he had defeated.

This power is called — "Doomsday Declaration"!

This power grants Shirou two kinds of strength.

The first type allows Shirou to wield the power of Nidhogg, the black dragon, which can even convert the World Tree into its own. Regardless of the enemy, even if the opponent is a 'disobedient god,' it can still devour their power. However, the success rate of this ability depends on the target's condition.

In other words, the lower the target's condition, the higher the chance of success.

In simpler terms, the lower the enemy's health, the higher the success rate of devouring them.

The second method allows Shirou to summon a 'Dark Domain,' just like the black mist exhaled by the black dragon Nidhogg. Within the 'Dark Domain,' he can summon the six venomous snakes controlled by the black dragon Nidhogg: Guin, Moin, Grabak, Grafvorud, Overnir, and Swafnir.

"'Doomsday Declaration'... Is this the divine power of Nidhogg...?"

Shirou closed his eyes slightly, sensing the divine power he received from the black dragon Nidhogg.

Then, he checked his current attribute values.

[Name: Orihara Shirou (God Killer)]

【Sex: Male】

【Height: 187cm】

[Race: Human]