Rukia Kuchiki vs. Sode no Shirayuki

 is the first major fight between a member of the Gotei 13 and their Zanpakutō during the Zanpakutō Rebellion. The battle between the two combatants began in Soul Society, moved briefly to the Human World, where Ichigo Kurosaki shortly joined the fight, and later continued and concluded in the Seireitei.

Prelude
Yoruichi Shihōin shows up at the Urahara Shop, where Rukia is recovering after her experiences during the initial stages of the Zanpakutō Rebellion. Following Yoruichi's update on the current situation, she confirms 6th Division Captain Byakuya Kuchiki is among the captains who are accounted for and is currently missing. When Rukia worries over this, Ichigo reminds her Byakuya is one of the most talented fighters they know and cannot be dead.

Despite these words, Rukia is still uneasy, and later this night, Noba teleports the other Mod Souls to Ichigo's house as he rests on his bed, where they inform him Rukia has disappeared. At the Urahara Shop, Kisuke Urahara surmises Rukia has likely returned to Soul Society. Despite Urahara's warnings, Ichigo demands Urahara open a Senkaimon so he can follow her to ensure she does not get hurt. Yoruichi agrees with Ichigo, giving Urahara little choice but to do as they ask.

In the Seireitei, Rukia rushes through the Sixth Division barracks towards Byakuya's office to see if he has returned. When she finds 6th Division Lieutenant Renji Abarai instead, her old friend enthusiastically greets her, unaware of her injuries, which results in an enraged Rukia punching him.

Renji informs her the search squad he sent out has yet to find Byakuya, but reassures her they would not have been able to defeat his captain, which makes Rukia smile. Despite this, she continues to reflect on the situation before she encounters the spirit of Sode no Shirayuki attacking Shinigami not far from her. Rushing onto the scene, Rukia demands her Zanpakutō stop attacking innocent Shinigami, but Sode no Shirayuki states she does not take orders from her any longer.

Elsewhere, Ichigo arrives in the Seireitei with Yoruichi, who warns him not to overdo anything and to pull back if anything starts to feel wrong with Zangetsu. Meanwhile, Rukia says she understands and asks why Sode no Shirayuki is using her power to hurt others who are innocent if she is free. Stating she will do as she pleases from now on, Sode no Shirayuki proclaims she will not spare the life of anyone who gets in her way. Saying she has no desire to fight with Sode no Shirayuki, Rukia tightens her grip on her Zanpakutō and begins to explain why she will anyway, only for Sode no Shirayuki to disappear and reappear in front of her.

Battle
Generating icy wind in her hand, Sode no Shirayuki throws it at Rukia, who dodges as the ground where she was standing is covered with ice. Leaping into the air, Rukia attempts to release Sode no Shirayuki, but nothing happens. Landing, she looks at her blade and notes the reports of Shinigami being unable to perform Shikai is true. Confirming this, Sode no Shirayuki states her energizing spirit no longer lives within Rukia's sword.

As Rukia expresses surprise, Sode no Shirayuki says Rukia had the ability to harness her power as a Zanpakutō whenever she wished, and she graciously allowed Rukia to do so. When she states the Zanpakutō allowed it because they never had a choice in the matter, Rukia admits she never thought of it this way. Manifesting her released Zanpakutō, Sode no Shirayuki proclaims things will be very different from now on and says it is time to use her power for herself.

As Rukia expresses surprise, Sode no Shirayuki states Rukia thought all of her power came from within and believed all of her power came from herself. Saying she is sadly mistaken, Sode no Shirayuki proclaims Rukia cannot do anything without her. As Rukia states she never thought all of her power came from herself, Sode no Shirayuki uses Some no mai, Tsukishiro. Seeing an icy circle forming under her, Rukia leaps away as a pillar of ice is created.

As Rukia says this is impossible, for the range of Some no mai, Tsukishiro should not be so large, Sode no Shirayuki states it should only be the area between the earth and sky within range of its blade. As Rukia lands on a nearby Roof, Sode no Shirayuki asks if this is what Rukia thought and slashes at her again, forcing Rukia to dodge as another ice pillar forms on the roof. When Sode no Shirayuki appears behind her in midair, Rukia tells her she must stop.

Blowing an icy wind at her, Sode no Shirayuki sends Rukia crashing into the ground. Panting, Rukia says Sode no Shirayuki really believes Rukia cannot do anything without her. Getting to her feet, Rukia chants the incantation for and uses '''Hadō #33. Sōkatsui'''. As the blast hits Sode no Shirayuki and creates an explosion, Rukia expresses surprise when the blue energy dissipates to reveal a spike-shaped barrier of ice, which shatters to reveal an unharmed Sode no Shirayuki.

As Rukia asks how she did this, Sode no Shirayuki notes she looks shocked and asks if Rukia is surprised by her possessing so much power. Stating she will gladly display her full capabilities since Rukia continues to underestimate her, Sode no Shirayuki appears behind Rukia and slashes at her. Blocking, Rukia is knocked back as Sode no Shirayuki appears above her and sends a wave of ice shards at her. As Rukia dodges, Sode no Shirayuki generates more ice shards.

Continuing to dodge the ice shards, Rukia thinks about Sode no Shirayuki and notes she is one of the most beautiful beings in all of Soul Society, yet is filled with hatred. Thinking about how Sode no Shirayuki wishes to destroy life and has nothing but venom for her, Rukia wonders if they have not always existed as one. As she wonders if they have not done so peacefully, in the past, Rukia holds up her newly-achieved Shikai while Kaien Shiba smiles and claps.

When Rukia uses Some no mai, Tsukishiro for the first time, Kaien smiles broadly. When Rukia uses Tsugi no mai, Hakuren and encases a nearby tree in ice, Kaien ruffles her hair and grins happily, causing Rukia to blush and smile. In the present, Rukia wonders if she has monopolized Sode no Shirayuki's power and caused her to suffer. When Sode no Shirayuki disappears, Rukia skids to a halt and looks around as Sode no Shirayuki says Rukia leaves herself open for an attack whenever she reflects on the past.

As Rukia notices Sode no Shirayuki standing behind her, the two slash at each other, creating an explosion of ice and snow. As Sode no Shirayuki leaps onto the roof of a nearby building, a panting Rukia stands in the middle of an icy platform before falling to her knees. As Rukia continues to pant, Sode no Shirayuki uses Tsugi no mai, Hakuren and sends an avalanche of cold air towards Rukia. As a large amount of ice is created by the attack, Sode no Shirayuki expresses surprise.

As black-red Reiatsu crackles in the center of the ice, two Bankai-enhanced Getsuga Tenshōs hurtle towards Sode no Shirayuki, who moves away as they crash into the building she was standing on. As the dust clears, Ichigo stands in front of Rukia in his Bankai, Tensa Zangetsu. Asking why Ichigo is here, Rukia states it is too dangerous to be here when they still do not know enough about why the Zanpakutō are turning against them.

Telling her to shut up, Ichigo asks if Rukia thinks he could simply sit back and wait. As Rukia expresses surprise, Ichigo looks over his shoulder and tells her to not worry, for even though they may not know the reason yet, they will definitely find the answer. As Rukia smiles and says she hopes so, Sode no Shirayuki lands in front of them and greets Ichigo. When Rukia states Sode no Shirayuki is strong and tells Ichigo to be careful, Ichigo says he knows this.

Raising his sword, Ichigo states Sode no Shirayuki is Rukia's Zanpakutō, so it is not surprising, and moves to Sode no Shirayuki, who fires ice shards at him. Dodging with Shunpo, Ichigo lands on a roof behind Sode no Shirayuki, who fires a crescent-shaped blast of ice at him. As the blast crashes into the roof, Ichigo moves to the ground behind Sode no Shirayuki. As the two stare at each other, Sode no Shirayuki asks Ichigo why he is holding back.

When Ichigo does not answer, a smirking Sode no Shirayuki says Ichigo is doing so because she is Rukia's Zanpakutō, so Ichigo has decided to go easy on her. Stating this is a poor choice, Sode no Shirayuki manifests her Zanpakutō once more and proclaims she will make Ichigo regret this. Moving back, Sode no Shirayuki uses Some no mai, Tsukishiro. As Ichigo expresses surprise at the icy circle underneath him, Rukia tells him to get away from there.

When ice begins to cover his left leg, Ichigo breaks it with his fist and leaps away as a column of ice forms. As he appears in the air next to the column, Sode no Shirayuki appears behind him and attacks, forcing him to block. As she smiles, ice begins to form on the blade of Tensa Zangetsu and covers Ichigo's hand. Leaping back, Ichigo breaks the ice once more, only for Sode no Shirayuki to appear in front of him and blow an icy wind at him.

As Ichigo is sent crashing into the ground, Rukia expresses concern for him before looking at Sode no Shirayuki, who looks over her shoulder and smiles, prompting Rukia to express surprise. As the dust clears, Ichigo stands with fragments of ice on his arm and a chunks of ice covering the right side of his face and his right shoulder. Asking if the ice hurts, Sode no Shirayuki says Ichigo has come to Soul Society to protect Rukia, prompting Ichigo to ask why this matters to her.

When Sode no Shirayuki states he is a fool, Ichigo asks if she thinks so and breaks the ice covering his face. As blood drips down the right side of his face, Ichigo grabs his wrist with his left hand and prepares a Getsuga Tenshō. When Sode no Shirayuki says it is hard to imagine what Ichigo can do with a frozen left arm, for he is still hesitant about killing her, Ichigo tells her to shut up. Smiling, Sode no Shirayuki states she shall teach him how such indecisiveness results in death.

As several currents of icy wind emanate from a glowing Sode no Shirayuki, Ichigo expresses surprise upon seeing Rukia attacking her from behind. As Ichigo expresses concern for her, Rukia slashes at Sode no Shirayuki, only for the latter to nonchalantly block the attack without looking. As they look at each other, Sode no Shirayuki pushes Rukia away. Landing in front of Ichigo, who calls out to her, Rukia looks over her shoulder and tells him to stay out of this.

As Ichigo expresses surprise, the Getsuga Tenshō in his blade dissipates as Sode no Shirayuki asks why Rukia has interfered. When Rukia tells Sode no Shirayuki to direct her hatred towards her if she has any, Sode no Shirayuki says Rukia is correct and proclaims she hates Rukia, which is why Ichigo must die. When Ichigo expresses surprise and prepares to move forward, Rukia stops him as Sode no Shirayuki states killing Ichigo is the best way to make Rukia truly suffer.

Proclaiming she will take away everything Rukia holds dear - her friends, her family, and her pride as a Shinigami - Sode no Shirayuki says Rukia will only be able to watch as this happens. Stating she understands, Rukia says Sode no Shirayuki truly is her Zanpakutō, for she can hurt Rukia deeper than anyone else can because she knows her so well. Telling Sode no Shirayuki she is beautiful, Rukia states this always filled her with pride.

When Rukia says having such a beautiful Zanpakutō for her sword made her smile, an angered Sode no Shirayuki proclaims she is not one of Rukia's belongings. Stating she is right, Rukia says she is now free, prompting Sode no Shirayuki to express surprise. As Ichigo expresses concern for her, Rukia proclaims she now releases Sode no Shirayuki, who expresses shock. Telling her it is time to put away her anger, Rukia looks up and thanks Sode no Shirayuki for the time they have shared.

As Rukia states the time they spent as one was great, Sode no Shirayuki asks if Rukia is saying she will continue without her. When Rukia confirms this, Sode no Shirayuki lands on the ground as Rukia states she will do so even if going on without Sode no Shirayuki causes her to lose everything and be forced to return to Rukongai. Walking forward, Rukia begins to chants the incantation for '''Hadō #73. Sōren Sōkatsui''' as Sode no Shirayuki asks if she truly intends to destroy her.

As Rukia begins to chant the incantation for '''Bakudō #61. Rikujōkōrō''', a surprised Sode no Shirayuki asks if Rukia really believes she can live and survive without Sode no Shirayuki being here. When Rukia continues to chant the first incantation, a shocked Sode no Shirayuki surrounds herself with an orb of icy wind. Walking into the orb, Rukia uses '''Bakudō #61. Rikujōkōrō''', which binds herself and Sode no Shirayuki together.

As Sode no Shirayuki expresses surprise, Rukia says she cannot forgive anyone who attempts to destroy what she must protect. As ice begins to encase her body, Rukia states she is not afraid to lose and let go of anything. As Sode no Shirayuki asks if she is willing to do this, Rukia says she shall let go of her anger, hatred, and sadness, for she and Sode no Shirayuki are separate. As Sode no Shirayuki tells her to not do this, Rukia states she releases her to be free.

Putting her hand on Sode no Shirayuki's chest, Rukia says she lets go of Sode no Shirayuki's beauty, the power she gave Rukia as a Shinigami, the memories of what they achieved together, and everything in their past, for all of what they shared has become a burden to her and to Sode no Shirayuki. As Sode no Shirayuki tells her she must stop, Rukia generates blue energy between her hand. As Sode no Shirayuki expresses terror, Rukia tells her she is now free forever and uses Hadō #73 Sōkatsui.

Aftermath
Sode no Shirayuki expresses surprise at her former master going to such lengths, while Rukia states Shinigami care about their Zanpakutō just as much as they care about their own lives, bidding farewell to the spirit of Sode no Shirayuki as she loses consciousness. At the last minute, Sode no Shirayuki tries to reach out for Rukia, but Muramasa appears and catches her hand before she can do so. Ichigo rushes to Rukia's side, but Muramasa comes up behind him and introduces himself. Ichigo demands to know more, and Muramasa reveals he is another Zanpakutō Spirit.