1 Million years ago

Hades arrived in the world of Bleach. The world was a dark and gloomy place to be in, locked in a cycle of decline and destruction. All of existence was a single, chaotic, primordial world overrun by Hollows that preyed upon the world's denizens.

They were drawn to negative emotions, fears, and spiritual energy, which were in abundant supply during these tumultuous times. Nothing was truly alive or dead. Everything followed the circle of Reishi. 

Souls and Hollows just existed constantly circulating through the motions one transforming into the other. 

There was only one thing that existed in this period. And that was 'the Underworld' or 'Hell dimension. In the future, after the separation of the three realms, if a spirit has committed heinous crimes as a Human or has not escaped to Hueco Mundo, it will be sent to the Underworld instead of Soul Society.

But since there were no humans yet, and the concept of life and death were not yet introduced, it was mostly empty. The Underworld did serve an important purpose though. 

The Underworld's integrity was, similar to the balance of Souls between the Human World and Soul Society, maintained by a balance of Reiatsu between it and the combined realms of the Human World and Soul Society. This was at that time simply everything else.

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What did this mean? 

This meant that there was a constant cycle of Reishi between the Underworld and the rest of the world. This was what essentially held everything together. 

A soul that was formed from Reishi would essentially grow up and then be devoured by a Hollow. This was part of the cycle of Reishi. After that, it was a matter of whether the Hollow could consume enough 'souls' or Reishi to sustain itself. 

If it couldn't it would return to Reishi. This malevolent Reishi would then flow into the Underworld to be 'cleansed' and then return to the Overworld. 

That was the cycle of Reishi and the rules on which everything functioned. This of course was not efficient. There was no progress only chaos. Everything went by chance and nothing was achieved. 

The world was in decline. But it was a slow-going progress. It might take 1 million to hundreds of million years until the cycle of Reishi would no longer be able to sustain itself, due to the Hollows just having a very big advantage. 

The amount of Reishi was diminishing as the Hollows consumed and grew stronger. 

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Hades arrived in the world and felt the energy this world functioned with. Reishi or Spirit Energy. It was the energy that your soul produced and Hades could feel the positive effects it had on him.

Since he was born as Hades, he had never trained his soul. It grew naturally but this would be a good opportunity for him to increase his soul's strength. 

It was also the perfect chance for him to combine all the energies that he had access to and make them one. 

He could feel a connection to the Underworld in this world as soon as he arrived here. He understood the reason and went there. He could feel the malicious energies trying to corrupt the intruder and push his spirit energy out of him. It was trying to dry his soul out of energy.

He of course didn't allow this to happen and pushed back. It was at that moment that he unlocked his own Reiryoku/Reiatsu. It was a cool and refreshing feeling for him as the energy flowed through his soul and out of it. 

He could feel the power it had and the potential it represented. He was glad that he was inside the Underworld dimension as the pressure and intensity of his Reiatsu might have caused widespread destruction and the world could not use this right now.

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Hades got to work, he used the chance this gave him to cleanse himself and strengthen his soul. 

He took control and ownership of the Underworld but he had no plans with it for now. He wanted to get his growth first. 

Hades meditated, something he hadn't done in years and tried to separate his soul from his physical body. This should not be hard for him as a god had a true form that should act as his soul. 

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As Hades meditated and managed to get his soul out of his physical body, he began the long and arduous process of cleansing his soul and fixing it. All the different energies he had acquired had caused some damage to his soul.

Hades was born with divinity and mana. After going to the Wizarding World he got a different type of magic energy. This might be confusing but it is like different flavoured drinks. They all have water in them (or most) but they are still different.

Next was Cursed Energy from Jujutsu Kaisen. This was something completely different and not something that you could just accept and use like Hades did. And of course, there is positive energy as well. 

The man in the world of Solo Leveling came after. This is closer to his original mana from the DC universe he got when he was born. 

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So what did this do to Hades? 

Well, the reason he was able to deal with those things was because he is a god and the god of boundaries. But he never got negatively affected by this because of his second wish. But the damage was still there and while it didn't negatively affect him, it would help him massively if he healed it.

So that is what he did. He circulated his spirit energy through his soul over and over again. This process took long. And the reason it took long was that, with every rotation, his soul would expel a tiny amount of waste, like some cultivation novel.

He was cleansing himself and after the process was over, Hades would then be able to form something of a mystical 'core' so to speak. He would then use this core to combine all the energies he had into one. 

The Spirit Energy acted as the matrix in between that held everything together and in the end allowed him to make the Omni energy. An energy that could accept new energy and allow Hades to use it with no problems.

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The years flowed by and the Underworld had changed somewhat. Around Hades, there was now a black gooey wasteland of waste, lol. 

His soul was shining as Hades was in the process of fusing all energies into one and completing what he came here to do. It was a massive success for Hades and he had grown, not stronger physically, but spiritually.

His soul was now much stronger and he had probably gained some form of minor divinity of energy or something. But he would have to see that later. For now, he had been in the Underworld long enough and he felt a powerful presence in the Overworld. 

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Hades was still in his soul state. He had dropped his physical body in the 'Gates of Hades' as he called it. It was a replica of the gates of Babylon that Hades had created. He turned the Inventory Curse into this by removing the limits and barriers.

He made his way out of the Underworld and followed the powerful presence he felt. 

When he arrived on what looked like a battlefield, if the dead Hollows were anything to go by, Hades stood before a ... young man. The man had a rather small and thin build. He wore pants that looked like those from a Shihakushō, leaving his chest bare. He had a coat that covered most parts of his upper body. 

What stood out most though were his eyes. They looked like he had yellow crosses inside, but when you looked closer you saw that it was actually four pupils in each eye. 

In his hand, he held a normal-looking katana that leaked energy from the blade. 

The man looked at Hades and studied him just as Hades did the man. Hades knew who this was but he wanted to make sure. 

"Did you kill all these Hollows?"

"I did.", the man said. His voice was a gentle and harmonious quality that was easy on the ears, conveying a sense of calm and comfort while still being perfectly clear. 

"I see. What's your name?", Hades asked. 

"I have no name."

"No name. Where did you come from?"

"I don't know. I just ... appeared here."

"So you appeared here and then decided to kill the Hollows. Why?"

"I- ... I'm not certain. It was ..."

"Instinct?", Hades tried to help him.

"Yes. Instinct. It pushed me to kill these Hollows and save the souls..."

Hades smiled at him. 

"What about you?", the man asked Hades.

"What about me?"

"Do you have a name?"

"Of course. My name is Hades. I am the ruler of the Underworld."

"Ah, the long night..."

"Long night?"

"Yes, that is the place where Reishi goes to sleep and then comes back cleaner."

"I see. Yes, it indeed does that."

"So you are ... Eimin."

"Eimin?"

"Yes, Eimin. The eternal sleep.."

"Ah ... a fitting name indeed. Well if you give me a name, I shall give you one as well.", Hades said.

Hades thought about it and since he wasn't very good at it, he decided to go with the original. No reason to complicate things. 

"How about Hatsuhinode, or Ray for short? The first rays of the sun, are called Hatsuhinode. So I think it fits."

"Hatsuhinode ... Ray ... I like it!", he said and smiled at Hades. 

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The two spent more time together and began to talk about the world as a whole and what seemed to be the problem. 

"I believe you were created by the world itself. I think you bring hope to the world. It was declining and with someone killing the Hollows, I believe that more souls could be created by the Reishi.", Hades told Rey.

"You are correct. The longer I am 'alive' the better I understand things. This chaos is not good for the world and it couldn't go on like this. I have to do something."

"Well killing the Hollows might help but you can't ever kill all of them as they spawn and without them, the cycle or Reishi can't go on. But that might be the solution to more Reishi."

"True. More souls means more Spirit energy released and that means more Reishi. It would help in the short term."

"Tell me Rey, what are those eyes of yours?", Hades asked Rey.

"Oh, these. They allow me to see the future."

"Is that so? But they do more than that don't they?", Hades asked with a smirk.

"Hm?"

"Haha, don't play dumb with me Rey. Do you think I will take them from you?"

"You couldn't. They are truly special."

"Oh? Hahaha. You are special in your own way. The amount of powers you have is ridiculous and you were just born too. But don't worry I won't take them."

Rey looked to be down there. He didn't have his smile anymore.

"Oi Rey, I really won't take them."

"It's not that. I know you won't. It's just ... the future I'm thinking about. Killing Hollows is only short term."

"I know, and if you want I can deal with the shortage of Reishi no problem. I-"

"No. I believe there might be another way that would be better."

"Better than just produceing more Reishi? Now I'm interested."

"... the world is so ... chaotic. I feel the need to change this. To change the way things work right now.", Rey said. He was deep in thought. 

"It seems you know something that you're not telling me."

"..."

"Haa, look Rey. You can tell me if it bothers you. We're friends now and that is something that friends do. So don't let it bother you and tell me when you feel like it, OK?"

"Thank you, Eimin.", Rey said with a smile on his face. It seemed the 'Almighty' was working fine and he had seen what he would become of him. 

But I would stop him if I could. I liked Rey and I didn't want to see him sealed and mutilated.