Byakuya's Betrayal: Revealed

 is an event taking place in the Zanpakutō Rebellion, focusing upon the pivotal incident in which Captain Byakuya Kuchiki, of the 6th Division, reveals his allegiance to the Zanpakutō's cause.

Prelude
After 10th Division Lieutenant Rangiku Matsumoto and 5th Division Lieutenant Momo Hinamori defeat their Zanpakutō Spirits, Haineko and Tobiume are secured inside a carriage despite their attempts to reason with their masters. Ignoring their pleas, Rangiku and Momo tell the Shinigami operating the carriage to take Haineko and Tobiume to the 4th Division barracks as they leave the area. In their wake, another figure leaves in pursuit of the carriage. As the two Shinigami run, Momo senses 10th Division Captain Tōshirō Hitsugaya's Reiatsu weakening as they head towards it.

Muramasa's Return
When Ichigo Kurosaki crosses their path, Rangiku crashes into him. Realizing she is sitting on Ichigo, Rangiku berates him for commenting upon her weight. Later, when Rangiku asks him if Hitsugaya is alright, Ichigo relays the aftermath of the fight to her. As the three of them realize something is wrong, Muramasa stumbles out of a Garganta. Panting heavily, Muramasa notes his body is not yet accustomed to Vasto Lordes before sensing the presence of Ichigo and the others.

When Muramasa states he and Ichigo are linked to one another, Ichigo states he is going to defeat him and says this is the only business they have together. When Muramasa raises his hand, Ichigo wonders if he will try to take control of Zangetsu again. Reassuring him, Zangetsu states the same trick does not work twice. Saying not being afraid of fighting him will be a fatal mistake for Ichigo, Muramasa coughs repeatedly, prompting Momo to note his unstable Reiatsu. As the air around him distorts, Muramasa binds Ichigo, Momo, and Rangiku with his spiritual threads.

Senbonzakura's Intervention
When Muramasa enters another coughing fit, the group is freed from his threads as blood streaks from Muramasa's eyes. Taking advantage of this temporary distraction, Ichigo charges at Muramasa. Blocking Ichigo's attack with his sword, Senbonzakura pushes Ichigo back as Muramasa smiles. When Ichigo asks Senbonzakura who his master is, Senbonzakura states he will find out soon and releases his Bankai, Senbonzakura Kageyoshi, which Ichigo notes is 6th Division Captain Kuchiki's Bankai. As the rows of blades separate into blade petals, Momo uses Bakudō #39 Enkōsen to shield herself and Rangiku from the attack. As Rangiku pushes Momo out of the way, Ichigo dispels the attack with a Getsuga Tenshō.

Commenting upon Senbonzakura's strength, Ichigo correctly identifies Senbonzakura as Byakuya's Zanpakutō spirit, prompting Senbonzakura to note Ichigo remembers him. Meanwhile, as the carriage moves along, the Shinigami guards sense a massive amount of Reiatsu being released. As one of them notes it is Byakuya's Reiatsu, a mysterious figure proceeds to subdue the guards, prompting Haineko and Tobiume to ask the figure what he means by doing this. At the battlefield, Momo and an injured Rangiku move into the forest to allow Ichigo to fight Senbonzakura alone. Realizing why Senbonzakura has the same Reiatsu as Byakuya, Ichigo states Senbonzakura is the one who attacked him last night before charging at him. When Senbonzakura sends Senbonzakura Kageyoshi towards him, Ichigo moves away.

When Senbonzakura walks into the clearing, Ichigo has vanished. Intercepting Ichigo's attack from above, Senbonzakura appears behind him and asks Ichigo if he believed such an attack would prove successful against him before pushing Ichigo back. Evading all of Senbonzakura's attacks, Ichigo appears next to Senbonzakura, who intercepts his attack again, forcing Ichigo to go on the defensive. As Senbonzakura observes Ichigo's movements closely, Ichigo creates several afterimages Ichigo appears above Senbonzakura, who blocks Ichigo's attack with his petals.

Reminiscing about his fight with Byakuya, Ichigo fires a black Getsuga Tenshō. As the attack sends him hurtling him into a nearby building, Senbonzakura pants heavily and decides to trap Ichigo within Gōkei. As Senbonzakura explains the attack, the sphere of blade petals contracts slightly before exploding. As Senbonzakura states Ichigo is finished, Rangiku calls out to him as Ichigo emerges unscathed, having donned his Hollow mask, prompting Senbonzakura to commend Ichigo's abilities.

Wondering if it is correct to kill Senbonzakura, Ichigo decides he has no choice but to do so. Asking Ichigo why he is hesitating, Senbonzakura activates Senkei. When Ichigo fires a black Getsuga Tenshō, Senbonzakura sends a large amount of blade petals at it with a slash of two Senkei swords. Colliding, the two attacks create an explosion, sending a shock wave hurtling throughout the area. When Ichigo's Hollow mask dissipates, Senbonzakura claims he gathered enough Reiryoku to withstand Ichigo's attack while Ichigo was hesitating. As Ichigo asks him why he thinks so, part of Senbonzakura's mask shatters.

The Betrayal
Clutching his exposed left eye, Senbonzakura wonders what happened. Apologizing, Ichigo states Senbonzakura has no chance of defeating him without Byakuya's assistance. Preparing to attack Ichigo once more. Senbonzakura is stopped by Byakuya, who tells him to stop. As the other Shinigami express surprise at Byakuya's sudden appearance, Rangiku wonders what he is doing here. Facing Ichigo, Byakuya tells him to pull back, prompting Ichigo to ask him if he is preparing to fight Senbonzakura.

Stating this is not the case, Byakuya fires '''Hadō #33. Sōkatsui ''' at Ichigo. When Ichigo asks him why he did this, Byakuya states he will not allow him to attack Muramasa. When Ichigo asks him why he is protecting Muramasa, Byakuya says he is doing this of his own free will. Laughing, Muramasa stating Byakuya has said some interesting things and asks Byakuya what motivates Byakuya the most. Stating his desire is to uphold his self-respect, Byakuya repeats his warning and states Ichigo will die if he continues to impede Muramasa's objectives.

Treacherous Revelation
The next morning, Ichigo relays the events to 8th Division Captain Shunsui Kyōraku, 13th Division Captain Jūshirō Ukitake, and 4th Division Captain Retsu Unohana. When 6th Division Lieutenant Renji Abarai refuses to believe Byakuya has really changed sides, Shunsui tells him to calm down. When Ichigo reveals Byakuya is working with Senbonzakura, a frustrated Renji walks over to a window as the Shinigami contemplate the current situation. Noting Captain-Commander Genryūsai Shigekuni Yamamoto is currently missing and Byakuya is now a traitor, Shunsui wonders what else is going to happen.

Stating Hitsugaya being able to recover Hyōrinmaru is the only good news they have, Ukitake outlines the main problem with the Shinigami's methods in regards to fighting their Zanpakutō. When Unohana reveals a Zanpakutō spirit is likely to be permanently destroyed if someone other than its Shinigami master defeats it, the other Shinigami express surprise at this new development as Ichigo asks her what they are supposed to do in combat with other Zanpakutō if this is the case.

When Shunsui tells them the only thing they can do is hold back, 8th Division Lieutenant Nanao Ise suggests they keep the information about Byakuya's betrayal a secret to everyone but the captains. Disapproving of this idea, Shunsui says rumors will circulate and affect troop morale if they begin keeping secrets now. When Renji asks him how Rukia Kuchiki will take the news, Ukitake says he will take care of this. Stating Rukia will be fine, Ukitake says she will have to accept the truth as they have.

Later, Rukia expresses shock at the news, prompting Ukitake to confirm Byakuya joining the Zanpakutō Spirits is the truth. As Rukia sighs, Ukitake tries to reassure her and states Byakuya may have some ulterior motive to joining the Zanpakutō Spirits' cause. Staring out of the window, Rukia wonders what Byakuya hopes to achieve by allying himself with Muramasa and the Zanpakutō Spirits. Meanwhile, inside the Zanpakutō cave, the Zanpakutō Spirits are surprised when Byakuya arrives.

Appearing behind them, Senbonzakura questions Byakuya's aims behind assisting him. Assigning Byakuya a task to prove his allegiance to their cause, Senbonzakura tells Byakuya to kill Sode no Shirayuki, who expresses surprise. Expressing surprises at this suggestion, the other Zanpakutō Spirits are initially against it, but eventually admit it makes sense, for killing Sode no Shirayuki would render Rukia's existence as a Shinigami pointless. Believing Byakuya is unable to complete the task, the Zanpakutō Spirits believe they have seen through Byakuya's deception and prepare to kill him.

Aftermath
Byakuya willingly defeats Sode no Shirayuki, much to the surprise of the other Zanpakutō Spirits, Byakuya travels to the 6th Division barracks with Senbonzakura, who hands Sode no Shirayuki's broken sword to Rukia. As Senbonzakura raises his blade in an attempt to cut Rukia down, Renji intervenes and blocks Senbonzakura's attack. As Saru and Hebi appear on the scene and preparing to fight Senbonzakura, Renji faces off against Byakuya.