In Hueco Mundo
Orihime, Chad and Calavera were sitting in some abandoned ruins.
Chad: Are you two tired out? We can call it a day.
Calavera: I can keep going. What about you Orihime?
Orihime: No, I'm fine. I was thinking how peaceful it was.
Chad: Peaceful? The enemy may come attacking at any moment, you know?
Orihime: That's true, but for us humans to be able to spend time in Hueco Mundo, help the Arrancars, and training hard to save the Shinigamis... It just feels kind of nice. I wish that this could last as long as possible. To continue helping one another and respecting each other's worlds so that we can all say there was no battle to start with.
Calavera: I guess I can see where you're coming from.
Just then, the three had their conversation interrupted by Apacci, who came alongside her other two members.
Apacci: What are you three doing lazing about? We got more training to do!
Sung-Sun: I'm sure they just want to catch their breath. No need to be impatient.
Mila-Rose: I think they're improving at a good pace. They deserve it.
Apacci: Fine... But once you guys rest up we're training even harder than before. Got it?
Chad, Orihime and Calavera all had a determined look on their faces.
All three: Right!
(Meanwhile) In the Royal Palace
(Y/N) and Byakuya had just finished a sparring match with each other with training swords. The two collapsed to the floor as they caught their breaths.
(Y/N): Phew... Fighting Captains are still as difficult as they were when I first encountered them...
Byakuya: You say that, but I'd say you're in a league of your own (L/N).
(Y/N): You think so? I may have the raw strength to go up against you guys but the gap in experience is the issue.
Byakuya: Don't sell yourself short. The experience you've gained in these last two years are vast.
(Y/N): I'm not trying to get down on myself or anything, I'm just pointing out the obvious. I do feel a massive improvement in my fighting skills. I just wonder how many years it'll take to close the gap in experience.
Byakuya: With the rate you're improving at, you'll be there in no time.
Just then, Rukia walked up to (Y/N) and Byakuya, although it seemed like she needed to speak to (Y/N) in particular.
Byakuya: Rukia, is something the matter?
Rukia: I'm sorry to interrupt your conversation but I wanted to ask for assistance...
(Y/N): What is it?
Rukia: Well, you two are... well the smartest among our group in a lack of better terms, so I wanted to ask for help for a certain matter.
Byakuya: And what might that be?
Rukia: Well... upon training, I've come to the discovery of the true power of Sode no Shirayuki.
Byakuya: I see. Can you give us the details?
Rukia: Well Sode no Shirayuki's true ability is to lower the body temperature of its user. But I'm unsure what I should do with that information nor how to properly utilize it.
Byakuya and (Y/N) looked at each other before giving their own input.
Byakuya: The sword is a simple extension of your reach. If your zanpakuto gives you such a power then it's safe to say that simply making contact with an enemy would provide the same effect.
(Y/N): I agree. However, that also comes with some obvious downsides.
Rukia: Such as potentially freezing myself, correct?
(Y/N): Yeah, but that doesn't mean you can't use that to your advantage either.
Rukia: But how would I possibly do that?
(Y/N): The colder the body gets, the harder it is to perform a bodily function. You can freeze blood or even vital organs. But that'll require you to do the same to your body before you can transfer that body temperature to someone else. I believe it's something you should practice before using it in real battle. If you're not careful you could very well kill yourself before you do anything to the opponent.
Rukia: Then what do you suggest I do?
Byakuya: We can take careful steps into seeing how much your body can take before negative effects start to show themselves.
(Y/N): And you're lucky enough to have someone here who can revive himself as the perfect test dummy if things get rough.
Rukia: Thank you. Both of you.
(Y/N): No problem. Say... Where is Renji anyway?
Rukia: Oh, he went to speak with Mr. Hyosube.
(Y/N): Huh... Wonder what that could be about...
(Meanwhile) In Soul Society.
Omaeda stood in front of where his family mansion used to be. Whatever the Quincies did to invade this time around forced his home out of existence.
Omaeda: What's going on? What happened? Why did the mansion disappear?!
Omaeda was taken out of his thoughts when he heard his little sister call out to him.
Mareyo: Big Brother... Please do not go. I'm scared. Please stay here with me.
Omaeda: No. I have to go.
Mareyo: Big Brother...
Omaeda: Mareyo, you're a smart girl, Mareyo, so I know you understand. Your big brother is not leaving you because I want to scare you. I am leaving so I can protect you, Saburo, Big Sister, Father and Mother, our neighbors Gondawara and Kanemitsu, and most of all,the Seireitei. That is why I have to go. You understand, don't you? Because your big brother is a member of the Court Guard Squads.
Omaeda's speech surprisingly made his little sister cry.
Omaeda: Come on, don't cry like that. I will come back safely.
Disaster struck as a newcomer landed right behind the siblings. Omaeda was able to detect who the opponent was immediately.
Omaeda: You're... The guy who stole Captain Soi Fon's Bankai!
The enemy, known as BG9, attacked Omaeda, piercing him in the shoulder.
Mareyo: Big Brother!
Omaeda: Mareyo! Y-Your big brother will be fine... Go and hide!
Mareyo ran off as BG9 continued to question Omaeda.
BG9: Where is your squad's captain?
Omaeda: Are you stupid or something? I really don't know where she is! Even if you did find out, my captain isn't going to lose to someone like you! So there's no reason to hide her!
BG9: You've refused to answer. I'll ask you another way.
BG9's robotic appendage stretched out, piercing a building and in the process impaled something.
Omaeda: The hell are you doing all of a-
Omaeda was cut off as he saw that his sister became a victim of BG9's impalement.
BG9: This is a relative of yours, correct? I do not require verbal confirmation. Though the visual conformity between yourselves is extremely low, the reiatsu conformity exceeds levels of 50%. Furthermore, I detect three other individuals with reiatsu conformity exceeding 50% with your own within a 30 meter radius of this location. If you refuse to answer again I will eliminate all of these targets immediately.
Omaeda didn't take BG9's threat well as he attacked the robotic quincy with his shikai out of sheer anger.
Omaeda: Get your hands off of Mareyo!
BG9 simply brushed off the attack and continued talking.
BG9: I have two queries. Firstly, should I take your response as a refusal to answer?
BG9 pierced Omaeda in the shoulder again.
BG9: And secondly, If I release this individual now, large quantities of bodily fluid will be expelled from the wound, resulting in death. Is this acceptable to you?
Omaeda didn't stop trying to attack BG9 despite his futile efforts. BG9 simply retaliated by impaling Omaeda again.
BG9: There's a possibility that your linguistic faculties have ceased to correctly function due to shock. I will grant you 15 seconds. I await your answer.
Omaeda struggled to get up but didn't give up.
Omaeda: You're not going to get away with this... You hear me!
BG9: 15 seconds have expired.
The arm of the quincy transformed into a gatling gun.
BG9: How unfortunate.
Omaeda: You bastard!
BG9 let off a barrage of bullets aimed directly at Omaeda. However...
The Quincy found his gatling gun to be broken. From a distance a voice could be heard.
"I was under the impression that Quincy used bow and arrows."
"It seems you are a little more advanced than I gave you credit for."
Soi-Fon arrived on the scene just in time to save Omaeda. Every single bullet that was fired at the lieutenant was stopped by his captain. Even BG9 was surprised.
BG9: There was no reading on my sensors.
Soi-Fon: Did you think the Captain of the Stealth Force couldn't hide her own Spiritual Pressure?
BG9: 9th Head of the Fon Clan,Captain of Squad, and Supreme Commander of the Stealth Force, Soi Fon... What is that appearance?
Soi-Fon: "What is this," you ask? With all that information on me, you ask what this is? It's Shunko.
BG9: That, I know. Shunko is the ultimate Hakuda fighting style, achieved by enrobing the back and shoulders with Kido. But yours was not perfected the last time we fought.
Soi-Fon: And you thought I'd leave it that way forever? After my battle with Yoruichi and helping (Y/N) discover how to use Shunko, I honed my Shunko as best as I could. And since then, I have pushed my ability to the limit, taking the technique further still.
The wind surrounding Soi-Fon increased in ferocity.
Soi-Fon: My Shunko is "wind". I have perfected a method of causing the reiatsu I release to flow like a vortex around my body indefinitely. As such, once I have activated my Shunko, I am now able to maintain it for as long as it proves necessary. You have my thanks. If you had not stolen my Bankai, I may never have honed my Shunko to this level of mastery.
In an instant, Soi-Fon closed the distance between herself and BG9.
Soi-Fon: Mukyu Shunko.
With a fierce gale of wind, Soi-Fon attacked BG9 causing a massive explosion in the area. BG9 was sent hurling into multiple buildings and defeating the robot for good.
Soi-Fon: I can't stay stagnant. (Y/N) is out there getting stronger for our sake. It's about time we get serious about the safety of the Soul Society and stop relying on his help.
(Meanwhile) In Hueco Mundo.
Urahara and Wiz were completing the final touches on something they've been working on to help the Captains who lost their Bankai to regain them.
Urahara: That's one issue down. We've successfully completed the Shin'eiyaku.
Wiz: Now all that's left is to deliver them to the Soul Society.
Urahara: Will you be coming?
Wiz: There's still a few things I need to secure while I'm here in Hueco Mundo, but I'll be sure to come as soon as I can with the rest of the group.
Urahara: I see. For now, I'll get in contact with Captain Kurotsuchi and inform him of our creation. He'll be able to get the Shin'eiyaku to all the captains as fast as possible.
Wiz: I'll leave you to it then.
As Wiz went off to do her own thing, Urahara began to contact Mayuri as he opened a Senkaimon.
*ring*
*ring*
Urahara: Hello? Oh, I got through! Hi there. It's me, Urahara. I've completed the method to reclaim Bankai.
To be continued.
Am I biased for having Soi-Fon defeat BG9 before she got her Bankai back? Yeah...
Do I think she should've been able to do this in canon? Also yes...
I'll admit that the timeline between the invasion and when Rukia and Renji (and later Ichigo) arrives is a bit weird so bare with me on the weird timeline of events that lead up to their eventual landing on the battlefield