54
In a matter of minutes, the pair of cultivators had left North Korea and flown across the border into China. They had to be slightly more cautious at this point since China actually was a great power, both in the mortal and supernatural worlds. Still, it was easy for them to avoid detection with the slightest bit of effort.
They flew until they found a mountain that was isolated enough for their purposes. The mountain they chose wasn't very tall. With its gradual incline and almost flat peak, it was more of a very large hill. It would work perfectly well for their experiments though.
The mountain wasn't tall enough to have snow cover and finding a small clearing they could use was simple. They gracefully touched down at the summit of the mountain, dismounting and storing their flying swords. They sat down in lotus positions, facing each other, and Onari set the warhead down between them.
"So… how do you think we should do this?" Onari asked.
Yu Wu shrugged, "We could just set it off. I'm sure we could survive a small nuclear explosion and that would be the fastest way to expose ourselves to the energy."
"... Let's make that Plan B. What if I slowly burn it, absorb the energy that burns off, filter it to you, and then you cycle it back to me? And then we just keep doing that until the energy is depleted."
"Won't that just blow it up?"
It was Onari's turn to shrug, "Maybe. Maybe not. I'm honestly just guessing here."
"What about a formation?"
"What do you mean?"
"Like, what if we put it in a special seal designed to absorb the energy and Qi, set it off, and then use the saturated seal to profit?"
"That would probably be the most efficient way to explode the thing… And we wouldn't have to absorb all the energy at once. We would even be able to carry the seal around as a sort of emergency reserve…" Onari mused, rubbing his chin.
"Can you create a formation like that?" Yu Wu asked.
Onari slowly nodded, "I'm… pretty sure I could. It'll take a bit of time though. And I'll probably need your help powering it so it can contain the explosion."
"But it's possible?"
"I believe it is, love."
Yu Wu clapped and grinned, "Can we watch it explode?"
Onari winced, "That… might be a bit harder to manage, but I'll see what I can do."
"Yay!" Yu Wu cheered, smothering Onari's face with kisses. "You're the best, hubby! I've always wanted to see a nuclear explosion!"
Onari sighed. Now he had to succeed. He pulled out his formation-crafting tools and materials. Yu Wu watched from behind him, hanging off his back with her arms around his neck. Onari took a calming breath and inked the first stroke of the formation.
Since this seal had to be strong enough to contain a literal nuke, Onari chose his best material to be the base of the formation. It was a small cube that was half ivory and half ebony. The cube had a strong relationship with Yin-Yang energy. Onari and Yu Wu had both spent years filling the cube with their respective energy type while maintaining an exact balance between the two primordial forces.
Onari coaxed his Qi to the surface, picking up his brush and dipping it in a pot of gold ink. Qi flowed from his core, down his arm, and into the brush and ink. Onari marked each face of the cube with a single stroke. The ink sparkled with hidden power.
Yu Wu watched as Onari began to draw several intricate designs. The completely white and black sides of the cube contained the formations designed to absorb the energy from the nuclear blast. The sides, where the ebony and ivory met, contained the seal that would keep everything within a pocket space.
Concentration was plastered across Onari's face as he slowly built the custom array from the ground up. The pocket space sealed within was expanded enough that the explosion wouldn't immediately burst the seal. He took the energy absorbing portion of the formation from another formation that he had made to help Kunou train in Senjutsu.
The Qi absorbing formation had greatly improved Kunou's skill and ability to train Senjutsu. With the formation, she no longer had to gather Qi naturally, which meant she had more Qi and more opportunities to train with that Qi.
Since Senjutsu was a skill-based art, Kunou's power level had improved by leaps and bounds in the last couple of years. Onari and Yu Wu could only use Senjutsu to heal and unlock their Touki, but Kunou could do that and so much more. She was basically a master with illusions, foxfire, nature magic, self-reinforcement, and tracking.
The most important aspect of the Qi absorbing formation was that it acted as a vacuum that sucked energy through a funnel and into a set storage space. For Kunou, the vacuum was aimed at the outside world and that storage space was contained within her body. For this nuclear-containment formation, the vacuum would be aimed inward, at the seal's pocket space, and the storage would be the cube of ebony and ivory itself.
An exhale from Onari breathed a breath of life into the sealing array. Lines of gold ink seemed to dance on the Qi-saturated material. There was a short, inaudible hum like the universe was satisfied with Onari's work. In an instant, two hours of work came together beautifully.
Onari let out a sigh of relief, allowing the Qi he was gripping to slowly fade back into his core. He set his brush down and hovered his hand over the cube. Even without touching it, he could feel the formation thrumming with life.
"Well… That should be good enough. Do you want to do the honors?" Onari said.
Yu Wu jumped to her feet behind him, "Yes! Let's get this nuke on the road!"
She picked up the cube and walked over to the nuclear warhead. A touch of Qi was enough for the seal to suck in the warhead. Yu Wu brought the cube back over to Onari. He would have the easiest time 'lighting the fuse' because of his affinity for fire.
Onari took the cube and reached inside the sealed pocket space with his Qi. After observing the warhead's makeup for a few moments, Onari found that igniting the mechanism was as easy as snapping his fingers. Yu Wu's hands joined Onari's on the cube.
They both started pouring Qi into the sealing formation to reinforce the matrix. Onari shared his view of the pocket space with Yu Wu through their bond. Yu Wu was basically vibrating in place with excitement.
"2… 1…" Onari counted down.
There was no sound from the nuclear explosion. Even as a force of nature unleashed its full might, the vacuum inside the seal was eerily quiet. A blinding flash of white filled their mental vision. With no air to fuel it, the explosion died out relatively quickly. It still felt like it lasted an eternity to Onari and Yu Wu's observing eyes.
Nature raged within the seal. The very building blocks of matter were split from their partners and they lashed out at the world with a vengeance. Time seemed to freeze as Onari and Yu Wu bore witness to one of the strongest mundane events in the natural universe.
Even for a cultivator, there are no words to describe a nuclear explosion. Many will try and all of them will fall short of the true mark. It is one of those unfathomably powerful events that could only be replicated by high-level cultivators or supernatural beings. And as Onari and Yu Wu watched the explosion unfold in their mind's eyes, they realized that they truly weren't that far off from being one of those unimaginable beings…
Onari felt the Qi absorbing formation kick into overdrive to try and take in the sudden surplus of energy. With the aid of Onari and Yu Wu's reinforcing Qi, the formation was just barely able to handle the energy of the initial explosion. And as the initial stress of the explosion faded, they watched as the radioactive particles created by the blast began to race to the ends of the seal and back the way they came.
Absorbing the energy within these particles would be slower and more difficult for the formation. It was still possible though. And that was why Onari created such a large area of sealed vacuum within the formation. The particles could race each other through the sealed space and be absorbed by the formation at its leisure.
Still, the amount of energy already absorbed by the formation felt like it was enough for a mortal to breakthrough into the Third Stage. Of course, a mortal wouldn't even be able to harness or contain the wild radioactive energy in the first place. Onari and Yu Wu had both surpassed ordinary mortality a long time ago though.
Onari looked at Yu Wu with a determined steely gaze. Now that she had seen the potential of nuclear material, Yu Wu was much more cautious about trying to utilize that energy for their own gain.
"I want to be stronger…" Onari said, sensing Yu Wu's discomfort through the bond. "I won't leave you behind to obtain that strength though. We can always find another way."
Seeing and feeling Onari's determination, Yu Wu took a steadying breath, "N-No… I'm ready. Let's do this…"
Onari nodded. His hand joined with Yu Wu's while they both kept one hand on the cube. The cube was brimming, almost vibrating, with energy. Slowly and carefully, Onari began to draw the tiniest strand of energy he could into his core.
He was intentionally drawing a small amount to start with. There would be time to test his limits later once they knew what they were dealing with. The energy bucked and writhed and bubbled as it settled into Onari's core.
Onari took in the energy in time with his inhale and he forced the energy to comply with his exhale. The violent nuclear energy was tamed and processed surprisingly easily. Yu Wu was right when she thought the energy would contain large hints of Death, but surprisingly it didn't contain much Decay.
The Decay within the radioactive uranium seemed to have been blown away by the explosion. Now, the energy was mostly Death and Potential. The Death of an Atom and the Potential for a new one.
As Onari cultivated the nuclear energy, a similar process was happening within Yu Wu. It quickly became apparent that Onari had a natural affinity to Death energy, most likely because of his own death and reincarnation. By the luck of the heavens, Yu Wu seemed to have an affinity for Potential. The Potential of having two cultivator parents. The Potential of bonding with Onari, one of the heavens chosen protagonists in this world. The Potential inherent in all humanity.
As Onari continued cultivating, absorbing bits of nuclear energy at a time before reaching out for more, he began to feel a change. Something was forming within him. Something that propped up his cultivation, that supported the very fabric of his immortal soul: one of his Nine Immortal Bones.