Sode no Shirayuki vs. Rukia! Delusion of the Heart

Amid a Seireitei ravaged by the Zanpakutō uprising, Rukia finds her own spirit, Sode no Shirayuki, freezing Shinigami solid and declaring she will no longer answer to her wielder. Cut off from her Shikai, Rukia is battered by the spirit's ice dances, all while reflecting on whether she ever truly appreciated the power she took for granted. Ichigo arrives in his Bankai to help, but Sode no Shirayuki turns her fury toward him, vowing to kill him so that Rukia will suffer.

Rukia intervenes, redirecting the spirit's hatred onto herself and offering a painful answer. Acknowledging how deeply her beautiful sword can wound her precisely because it knows her, Rukia chooses to release Sode no Shirayuki entirely, binding them together with Kidō and striking with Sōkatsui to sever the bond and set the spirit free. As the battle ends, a mysterious figure catches the falling spirit and introduces himself to Ichigo as Muramasa, revealing that he too is a Zanpakutō spirit.

Rukia battles her rebellious Zanpakutō Spirit, Sode no Shirayuki, and discovers she can no longer use her Shikai. Ichigo arrives in Bankai to assist but is targeted by the spirit. Rukia chooses to release Sode no Shirayuki, binding them with Rikujōkōrō and defeating her with Sōren Sōkatsui to set her free. Muramasa appears, catches Sode no Shirayuki, and reveals to Ichigo that he is a Zanpakutō spirit.

An anime-only episode of the Zanpakutō Unknown Tales arc, adapting no chapters. In place of the usual short, Ichigo reluctantly hosts the Arrancar Encyclopedia while Gin steps aside, struggling to get Starrk, Baraggan, and Harribel to cooperate. Featured techniques include Some no mai Tsukishiro, Tsugi no mai Hakuren, Getsuga Tenshō, and the Kidō spells Sōkatsui and Sōren Sōkatsui.