Keiko watched from his dimension as the fight went on, his original plan was to kill of all people while taking in few who looked interesting for experiments but as he watched the fight he observed a peculiar situation occur Yhwach from time to time-powered up and then suddenly lost everything the moment Aizen attacked him.
Changing his EMS to Rinnegan he observed the link between Yhwach and his people which seemingly transfer Reiatsu from one person to another with a single chain going into space which seemed different then the entire circuit network. Keiko smiled as he looked at the entire picture. His Vasto Lorde either killed or sealed people which were deemed worth and completed their mission in the Human world meanwhile Arrancar which were sent off to completely swept the world of Hollows, sealing all higher form of Hollows and Quincy which were left behind. Aizen on instruction from Yhwach didn't leave any forces for backup or such purpose thus making it easier for Keiko's forces.
With both forces done with their world, Keiko brought them all in his dimension while also releasing his Bounts army which was specialized in sucking out the soul force of different species. Thus those which were deemed to have potential will be sealed or taken prisoner while the rest will be turned into Liquid energy to become an energy fuel seal for Hogyoku's which Keiko had created.
With everything in place, Keiko watched as the real Yhwach jumped into the battle and sealed Ichibe's Bankai while sucking energy from Aizen.
Yamamoto who after Keiko's training fought with minimizing his power outlet thus managed to suppress the seal Yhwach used.
Seeing this as a right opportunity to jump into the fight, with a wave of his hand Keiko opens the dimensional gap. 7 Vasto Lorde jumped out of the gap and attacked the nearby fighting Shinigami and Quincy people luring them away from the Aizen and others fighting area while 10 Arrancar Jumped onto Gerard Valkyrie the heart of the soul king and Pernida Parnkgjas the left hand of Soul king, both of which worked under Yhwach.
With the assurance of his future precious experiments secure, Keiko jumped into the battle himself while the remaining 10 Arrancar and 43 Vasto Lorde's watched the battle from the tear, Keiko at fight arrived near the weakened Aizen and using 5 of the most powerful Hyogyoku he had in his possession to erase the Consciousness within Aizen's Hyogyoku which was embedded into his body. With this he placed the last piece of his plan in place, using his Hyogyoku Keiko slowly started taking over the Aizen as a whole, erasing his and Yhwach's presence from with his Body and soul-making them under his control.
Keiko was interested in the power of Aizen's Bankai, he from his memories remembered that Aizen could at the final moments was even able to affect the senses of Yhwach after the lateral has already absorbed Soul King.
With Aizen under control, Keiko arrived behind Yhwach slowly releasing his power to 2 God tree little more than what Yhwach had.
Keiko standing behind Yhwach slowly said: Are you ready to dance?
All-purpose to fight Yhwach out in the open was to lure out parts of the soul king which were hidden into the world he had used his EMS to make soul king make the part come to him but didn't get any response thus concluded that the parts must have formed their consciousness somehow with utter loyalty toward Soul king.
Yhwach turned back and found the person which he found to be most threatening. Keiko for Yhwach was an entity which was outside the realm of his understanding, from his origin to powers, Yhwach even with the memories of Soul King and his lower gods knowledge wasn't able to understand Keiko's entity. Thus after thinking a lot, Yhwach made many different plans on how to deal with Keiko.
Keiko seeing Yhwach simple standing there looked around and found the 7 Vasto Lorde which were sent to lure people away had done their job smiled and waved his hands. Within the Space came all 10 remaining Arrancars and 47 Vasto Lorde, without wasting time, Arrancars jumped into Yhwach while Vasto Lorde went after Yamamoto and Ichibe who were both delighted to see Keiko.
Without caring much about the surprise reactions of Yamamoto and Ichibe. Keiko controlling Aizen created an illusion around the entire battlefield making it seems like Keiko is supporting Yamamoto and Ichibe.
Yamamoto after ignoring the first surprise attack from an Arrancar looked at Keiko and screamed: Keiko, why are you just standing their help us?
Keiko didn't say anything but only kept looking with his ever glowing smile.
Ichibe who under the direction of Soul King kept an eye on Keiko immediately understood what is going on and screamed: Bastard I treated you as my son, are you going to betray me.
Keiko ignoring the cries turned his head and looked at Yhwach who was fighting the Arrancar.
Yamamoto who was surrounded by 10 people understanding the situation and understood that he and Yhwach will die in this battle thus immediately decided to bring down everyone here along with him, screamed in anger and shouted: Bankai: Zanka no Tachi
A burst of energy released in the air before a huge pressure falls from the sky and a pillar of fire rose in the sky. All forces regardless of Shinigami, Hollows or Quincy stopped fighting and looked at it from a distance.
Keiko seeing this smiled and raised both his hands and released a beam of power into an unknown space and said: Seal.
Immediately afterward the energy overflowing out of Yamamoto's Bankai stopped. It turned into nothing more than an ordinary sword. Seeing this everyone got stunt.
Keiko smiled and looked at Yamamoto and Ichibe and started explaining: Do you both remember my trip with Oetsu to meet the Zanpakuto spirits? Why do you think I wanted to visit them? Let me explain this to you. Do you remember the Zanpakuto rebellion? While most of the soul society was running around playing as they please. I was observing the situation very closely. Where you all chaos I saw an opportunity. Zanpakuto funny little things, Let me explain how Zanpakuto's are formed. Each time when someone dies in any world regardless of their race human, soul or Hollows their soul during the process of being reborn in another world like let's say A human soul transmitting into the Soul society cleanses itself. During this said Cleansing the soul not takes a person's memories but also their soul identity thus when the process is done the little identical soul is standing there growing while being connected to your real soul. This identical soul is almost identical to your personality and slowly while absorbing energy present in the world which they exist in which is Soul Society the Home of Soul King himself. Then as the energy absorbed at denser and denser within that identical soul, the identical soul turns into what we can call a spirit after being trapped into a Zanpakuto which Oetsu did after finding them turns into Zanpakuto Spirits. Now you must be thinking if every characteristic of a Zanpakuto is copied from a person's soul then why do spirits have such different personalities right? Well, the answer is very simple actually and something which I learned from a very good friend of mine - Because they don't like being trapped. You trap them within your Zanpakuto and slowly start merging within your soul making their soul power your own. But now you must be thinking that there are many Zanpakuto which are very old and are used by many different Shinigami thus how can they be made out of single identical souls? Or like why do some Zanpakuto don't give much trouble to their wielder and helps them. Well the answer, in this case, is also quite simple. Everyone believes they are different but in the end, people are not that different sure your souls are unique but when it comes down to it many people are somewhat similar thus when they die they release the same time of energy wave which acc.u.mulates into a singular entity like for example Hyorinmaru. The ice entity became what it is today after absorbing the energy of more than 1000 soul energy or like your own Zanpakuto spirit Yamamoto Ryujin Jakka with the energy of who knows how many souls. Each spirit after absorbing each energy change, some became arrogant and all might while some remain modest and outgoing thus making each spirit unique in itself and the power it wields. So what I did here was quite simple. I after visiting each Zanpakuto in their Habitat made them absorb some of my energy, thus corrupting them with my power. Unlike the normal process when the soul loses it's power when it is cleaned my soul was within its perfect form thus making each and every Spirit which live in their inner world subdue to my energy. In a simple world, you can say each and every Zanpakuto there are in the world, all of them belong to me.
Ichibe and Yamamoto's face turned Ashed as they understood the meaning behind this, they have lost everything. All their weapons have been turned useless. Keiko taught them, Kido, thus he knew everything they could do and now their Zanpakuto which was their partner is every fight they had ever been had turned into an enemy's weapon.
Seeing this, Keiko waved his hands turned his Vasto Lorde thus signaling them to fight.
Seeing the signal, one by one like wolfs jumping onto defenseless Sheep attacked Yamamoto and Ichibe.
Keiko done with them turned to Yhwach who was bearly able to stand with only a right hand and a very injured stomach. Keiko seeing this smiled and decided to join in on the fight.
Black mass slowly started leaking from Keiko's hand turning into the shape of a simple Shundao sword with
Using Kamui Keiko appeared behind Yhwach and took out the remaining hand completely ignoring the Blue veins which Yhwach had for protection. Yhwach using his powers started reattaching the arms using energy veins which restarted healing the arm. Seeing this Keiko moved his sword back once more and said in a low voice: Bankai: Zanka no Tachi Higashi: Kyokujitsujin. A huge burst of fire quickly spread onto the Black blade. Yhwach who was into the process of healing his arm seeing this knew about Yamamoto's Zanpakuto's powers to eradicate whatever it touches into nothing. Seeing this Yhwach decide to abandon his hand, and moved away.
Escaping the attack, Yhwach decided to use the hidden card which he had hidden away to stop Yamamoto's Bankai in case the fight drags out. Using his power to bring forth a specially modified Arrancar which Aizen on his instructions using the data he had gathered on experimentation with Shinigami and Hollows created to trap Yamamoto.
Keiko seeing this smiled and whispered: Scatter: Senbonzakura, making millions of cherry bloom cutting the Arrancar which Yhwach bought out into meat slump.
Seeing his hidden card fail, Yhwach turned to seek help from his companion and saw no one was around with all the connections with his people either destroyed or with other party energy almost drained. Realizing this, Yhwach turned to Yamamoto and Ichibe and show both of them being nailed to a wooden block with their arms ripped out.
Yhwach finally panicked and moved his head back to the monster he was fighting. But before he could completely turn his head something grabbed it and forcefully moved it near Keiko. Keiko still having is all-natural heavenly smile said: Rinnegan: Human Path soul absorption.
Yhwach started screaming, slowly painfully his soul ripped out of his body, and Keiko absorbed it. Keiko closed his eyes and started watching the memories of Yhwach and found the memories of Soul King within them during his God-hood days.
Seeing them, Keiko smiled and turned his attention to one of the Arrancar under him, The name of the Arrancar was Kojito given to him by Keiko, Kojito who was standing among other Arrancar moved forward and came in front of Yhwach and took a piece of hair from his head and ate it, and slowly started changing turning into Yhwach himself.
Keiko waved his hand and open the space in which 2 Arrancar took the now dead body of Yhwach and disappeared. Aizen who till now was acting along with Keiko, changed his illusion making it so that both Yamamoto and Ichibe had died after a brutal battle meanwhile Keiko is also gravely injured.
With this, the now fake Yhwach moved into space and entered Royal Palace along with 7 remaining Arrancar following him.
Keiko re-entered his dimension and started observing the game once again.
Slowly, the fake Yhwach and the Arrancar forces moved into the deeper and deeper into the Soul Palace with the map, Keiko had provided them with. Leaving behind dead and deeply wounded in their path. Tenjiro with deep scars on his body with almost no energy left, Kirio with alone her upper half left behind, Senjumaru too deeply wounded and finally, Oetsu whose arms and legs were cut off and was placed on the broken sword to bleed out.
Keiko just kept on watching from the shadows to catch the bigger fish. Slowly the Arrancar with the fake Yhwach left to go around Royal Palace to find for anything which can be deemed useful.
While Fake Yhwach went forth and entered the Royal Hall were sealed Soul King was placed. Fake Yhwach arrived in front of it and raised his hand to cut the soul king when a dark matter from the shadows attacked Fake Yhwach, seeing the fish finally taking his bait, Keiko quickly jumped in and planted various seals around the Mimihagi the only part of soul king which was still loyal to him using Ichibe's bankai which specialized in it. Done with trapping it, Keiko didn't waste any time and used the device which he specially crafted for this, a huge pot, using his 3 god trees powers, Keiko slowly transferred all the black mass of Mimihagi into the pot thus crossing final goal from this world. With the battle over, Keiko informed all his troupes to return to the human world and resume there Human body collection activity.
Keiko reabsorbed the black matter in which he formed the sword into his body and went out of the Royal Palace. Firstly he met Kirio to who he explained that using all the powers he had resealed Yhwach into a space vortex thus ending the war and also how Yhwach had destroyed both the world of the hollows and the humans thus, breaking the world cycle. Explaining to her that the space vortex which took Yhwach away lead to another world in which Yhwach will continue to gain power and destroy more worlds and finally, the concept of world seeds and how he is planning to enter space vortex himself to save and protect other worlds from whoever tries to harm it and lastly asking if she would like to join him or rest now that she is about to die. Like every being out their who clunches to life, Kirio seeing the opportunity to do good decisions to enter the world seed. Similarly, Oetsu, Tenjiro and finally Senjumaru all entered the world seed in which Keiko presented them with various subject thus expanding their knowledge sphere.
With the Royal guards done, Keiko moved toward the Shinigami society explaining to them the destruction of both the Hollow and Human society. before finally explaining that Soul king has assigned a new mission to him. The mission to protect other realms from an entity like Yhwach, which has already destroyed this world's order.
Keiko left them with the choice to either join him or remain here with the Soul people with the only place Hell being open to them.
Seeing their choices of being under Keiko or in Hell almost everyone chose to enter the world seed and work for Keiko. While some had their reservation. Watching the situation from the sidelines Keiko throws another bombshell among them, stating that if Shinigami wants they can have the normal Soul Society residents enter the world seed too but only with free consent and anyone who wants to enter and look around is also available if anyone holds any reservation. Soon after worlds, both Shinigami and Soul Society residents entered the world seeds.
Done with everything Keiko moved back into the Human worlds were slowly all the Human bodies were placed into a Hibernation chamber and kept inside Keiko's dimension.
Collecting everything, Keiko entered the world of Hell, with all 13 Hogyoku with him. Keiko using his full speed passed layer by layer arrived at the Lowermost Level. And started absorbing the Souls which were trapped into Hogyoku making them more power, releasing all his 5 god tree powers, Keiko suppressed the guards and kept on collecting the soul cleaning out the hell. After being done from top to bottom, using the Quincy powers, Keiko started absorbing Hell's essence itself thus gaining control over the Hell guards and the connection between them.
With Hell as a personal live dimension under his control, Keiko moved to the soul society and started exploring it, absorbing the creatures such as Dragons.
With his huge experience with both Dragons from Harry potter world and energy research into Reiatsu, Keiko being deeply interested in them started researching. Dragon mainly found within western Londer leaving as protector of the people from Hollows while in the shadows. Keiko started understanding that the so-called Dragon was a mass of energy which had enhanced formes which looked like dragons, which changed shape after absorbing a particular kind of energy like, if they absorbed negative energy they turned into what people referred as Dark dragon but in reality was such a mixer of Dark element from emotions mixed with concentrated energy.
Seeing them form energy of their own gave Keiko a new idea regarding the energy in general. With his experiment done Keiko absorbed all the so-called dragons into Hogyoku and left to meet Ichibe and Yamamoto both of whom were tied from the pole and left behind after the fight.
Keiko walked into their cells and removed their shackles and brought them down from their Poles. Yamamoto and Ichibe both were heavily injured with heavy blood loss after being Tied up for the past two weeks when Keiko was playing around with dragons and other things.
Keiko slowly lifted one of them and placed them in White Bone Hell the invention made by Tenjiro but was later modified by Keiko in his image, the Hot spring water not only cleans any damaged Reiatsu but also slowly commends the Reiatsu network out of which Shinigami's body parts are connected with. Thus fastening their Healing powers.
After cleaning them of the damage and recovering their body loss using Blood Pond Hell, Keiko started using his own invented Kido art and started healing them.
Both Yamamoto and Ichibe after the Blood Pond Hell gained consciousness but both chose to be completely silent and kept their eyes closed.
Keiko slowly healed them completely. Slowly making them about to stand on their own then walk. No one said a single word.
After several days Keiko placed Tea for both of them and seat down before them. As all of them enjoyed the Tea in silence, Keiko broke the month's silence: I'm planning to move from this world. I want both of you to retire and stay comfortable. I have already taken care of everything.
Ichibe slowly placed his cup down and asked: Why?
Keiko: They took someone from me.
Ichibe: Who are they?
Keiko: Someone Soul King is working under.
Ichibe: Then they must be powerful? Why don't you just quit? Retire with us. Stay here.
Keiko instead of replying only smiled and took a long tea sip.
Ichibe: How sure are you?
Keiko: About 5% after absorbing Yhwach.
Yamamoto who was only listening with his eyes closed opened his eyes a little and looked at Keiko who was giving off his heavenly smile.
Ichibe: Do you need our help?
Keiko: No I just want to make sure you're Okay when it begins. Have you ever seen me do something I'm unsure about?
The silence befalls on the room they were drinking tea once again.