Tōshirō Hitsugaya vs. Hyōrinmaru

Tōshirō Hitsugaya vs. Hyōrinmaru is the conflict between the 10th Division Captain Tōshirō Hitsugaya and his amnesia-stricken Zanpakutō spirit during the Zanpakutō Rebellion.

Prologue
As Ichigo Kurosaki presses ahead in his search for the missing captain Byakuya Kuchiki, he stops for a moment. He senses the reiatsu of someone familiar. He runs over to a nearby rock formation, in order to get a better look of the surroundings. The rock he is standing on turns to ice, as he is attacked by several ice spears. Ichigo easily disposes of the attacks. While he stares out of the vast landscape, four ice dragons emerge and forces Ichigo on the defensive once again. Ichigo then sights his attacker. He asks who the Zanpakutō spirit is. However, the figure simply asks if he is Ichigo Kurosaki. Ichigo confirms this and asks why does the Zanpakutō spirit know his name. The spirit then notes that Ichigo seems quite strong. Ichigo asks the mysterious spirit to go on, to which he reveals that Muramasa instructed the Zanpakutō spirits to not fight Ichigo. Ichigo finds this interesting and wonders why Muramasa would say that. The spirit's response is that he would like to know why as well. He then surrounds Ichigo with four ice dragons. The dragons circle him before trapping Ichigo in a single pillar of ice. As the figure moves to walk away, Ichigo breaks free with his Bankai release. The Zanpakutō spirit is intrigued that Ichigo used Bankai. Ichigo confirms it as he is asked if his blade is a Zanpakutō. Ichigo confirms once again, which the Zanpakutō spirit asks for the name of Ichigo's Zanpakutō. Ichigo asks why does he care, as the Zanpakutō spirit looks down in contemplation. Ichigo wonder what is the spirit thinking, as the Zanpakutō spirit asks if Ichigo is his master. Ichigo is confused by the Zanpakutō spirit's question.

The figure proceeds to walk away again, stating that he has no business with Ichigo if he is not his master. Ichigo then asks him if he does not know who his master is, to which the man responds that he does not know the name of his master, nor his own. As Ichigo protests, he activates Sennen Hyōrō, surrounding Ichigo with ice pillars. Captain Tōshirō Hitsugaya then emerges, confirming that he is indeed Hyōrinmaru, which causes the Zanpakutō to turn around promptly. Hitsugaya states that he is his Zanpakutō. Hyōrinmaru quickly refutes this claim, stating that a mere child cannot wield his immense power. He is surprised by Hyōrinmaru's judgment, asking whether Muramasa had something to do with his memory loss. Hyōrinmaru explains that he merely lost all of his memories once freed from his master, and that his true goal is to find his master. The Zanpakutō spirit continues, stating that Hitsugaya will have to prove his worth, in order to be considered his master.

Battle
Hyōrinmaru uses his enhanced speed, deftly appearing behind Hitsugaya as their blades clash. Hitsugaya then backs off as Hyōrinmaru charges at him, kicking a cloud of dust into the air. Hyōrinmaru throws Hitsugaya into a nearby rock wall. He charges once more before being thrust into the air by the strength of Hyōrinmaru's strikes. However, he retaliates by binding Hyōrinmaru with Bakudō # 63: Sajo Sabaku.

Hyōrinmaru looks in wonder at Hitsugaya for several moments before telling him that his attempts to subdue him are fruitless. He proceeds to freeze the Kidō, shattering it into nothing as Hyōrinmaru's reiatsu causes dark clouds to loom over the surrounding area. Hyōrinmaru summons an ice dragon from behind him as Hitsugaya stands ready for the next attack. Ichigo calls out to Hitsugaya, only for the ice prison of Sennen Hyōrō spiral around before eventually closing on him. Hitsugaya shouts to his Zanpakutō spirit to stop, telling him that he is his opponent.

Hitsugaya releases Hado # 31, Shakkahō, which Hyōrinmaru catches effortlessly and freezes it within his palm. Hitsugaya then leaps forward to attack as Hyōrinmaru repeats his statement. The ice dragon behind Hyōrinmaru then attacks Hitsugaya in mid-air, forcing him into the ground in a flurry of ice. However, Hitsugaya emerges unperturbed, asking Hyōrinmaru what his instincts tell him to do. Hyōrinmaru divulges that he seeks a place in which he belongs, causing Hitsugaya to reminisce about his past with his Grandmother and enabling him to summon the willpower to release his Shikai. As Hitsugaya releases Hyōrinmaru's Shikai, thunder crackles from the sky, as an ice dragon forms before them. Hyōrinmaru is surprised at this, as Hitsugaya tells him that he will make him remember everything. He momentarily ponders over using the technique in Shikai, but charges at Hyōrinmaru nonetheless. He then utilizes Ryūsenka and encases both himself and his Zanpakutō spirit within it. Meanwhile, Ichigo uses Getsuga Tenshō to break free from Hyōrinmaru's prison.

As he escapes, he calls out to Hitsugaya. Inside the ice, Hitsugaya implores Hyōrinmaru to try to get him to remember the one who heard his voice. He shouts out the name of his Zanpakutō, which causes Hyōrinmaru to remember who his master is. As Ichigo looks on, the Ryūsenka encasing both Hitsugaya and Hyōrinmaru shatters and his Zanpakutō gently carries his master to the ground below.

Aftermath
Ichigo Kurosaki continues his search for Byakuya Kuchiki after encountering Hyōrinmaru. Tōshirō Hitsugaya is able to get his Zanpakutō spirit to return to him. Hyōrinmaru recalls his memories of his Shinigami master after Hitsugaya battled against him. During this event, Muramasa is panting heavily in what appears to be a forest area in Hueco Mundo. He stands before a weakened Hollow, stating that his time is running out. He walks over to it and firmly grasps its head. Purple reiatsu flows forth into Muramasa's body as the Hollow groans in pain.