Ichigo Kurosaki vs. Grimmjow Jaegerjaquez: Rematch

 is a fight taking place during the Arrancar Invasion between Ichigo Kurosaki and Grimmjow Jaegerjaquez, who was previously demoted from the rank of Espada, acting as the second confrontation between the two and Ichigo's first time intentionally using his Hollow mask.

Prelude
In the Visored Study Chamber, Ichigo Kurosaki continues training to extend his Hollowfication time limit against Hiyori Sarugaki, but when their session ends for lunch, Shinji Hirako is less than impressed that Ichigo can only maintain his Hollow mask for a little over ten seconds and ruminates on how the Hōgyoku awakening at the end of December means that they have a little over two months for Ichigo's training and will thus need to increase his limits as fast as possible.

Meanwhile, in Las Noches, Grimmjow Jaegerjaquez attends the Arrancarification ceremony of Wonderweiss Margela alongside Coyote Starrk, Tier Harribel, Ulquiorra Cifer, Nnoitra Gilga, Luppi Antenor, and Yammy Llargo, where Sōsuke Aizen temporarily fully awakens the Hōgyoku by briefly fusing with it in order to create Wonderweiss. Once this is done, Aizen reminds Ulquiorra of the order they discussed a month prior and instructs him to carry it out while taking anyone he wishes along with him prior to noticing Grimmjow sitting above and inviting him to join Ulquiorra as well.

Some time later, in Karakura Town, a Garganta rips open in the sky to reveal Grimmjow, Yammy, Luppi, and Wonderweiss standing within. As Yammy notes that they picked a good spot because there are combatants with strong Reiatsu below them, Luppi notes that these are Shinigami and likely the reinforcements from Soul Society that the sixth Espada told them about, but snidely corrects himself and addresses Grimmjow as the former sixth Espada after turning to him. However, Grimmjow simply asserts that the man he wants to kill is not down there and leaps away from the Garganta, startling Yammy, who is told by Luppi to let Grimmjow go since the latter is worthless now that he has had his tattoo burned off and is no longer an Espada.

During this, in the Visored Study Chamber, Love Aikawa and Kensei Muguruma restrain Ichigo as the latter attempts to leave and respond to the Arrancar arriving. When Kensei asserts that he is not ready yet and Love suggests that he let his allies from Soul Society handle this since that is what they came here to do, Ichigo counters that he has been training for this too and needs to take the opportunity while he can. Suddenly, Shinji pulls Kensei off of Ichigo by the strap of his shirt and orders him and Love to let Ichigo go, allowing Ichigo to run up the stairs and move into the sky while Kensei continues to protest this decision. Before Ichigo can get too far, Grimmjow appears in the air before him and declares that he has been looking for Ichigo, who asserts in turn that he has been waiting for Grimmjow.

After declaring that he will show the latter how much stronger he has become, Ichigo draws his Shikai, Zangetsu, and activates his Bankai, Tensa Zangetsu, in a burst of black Reiatsu. When Grimmjow scoffs at this since Tensa Zangetsu could not stop him during their last battle, Ichigo reminds him that Tensa Zangetsu gave Grimmjow the scar across his chest, to Grimmjow's irritation, and inquires about what happened to his left arm. In response, Grimmjow claims that he threw it away because he only needs one arm to kill Ichigo, who concludes from this that he does not need to hold back. With a smirking Grimmjow promising that he will die extremely fast if he does, Ichigo mentally notes that he has exactly eleven seconds to finish Grimmjow while Hollowfied and pulls his hand down in front of his face to summon his Hollow mask in an explosion of black Reiatsu.

Battle
When a shocked Grimmjow demands to know what this is, Ichigo asserts that he does not have time to explain and rapidly moves to Grimmjow with Shunpo before attacking him with Reiatsu trailing off his blade in a powerful slash that Grimmjow barely draws his Zanpakutō in time to block. As Grimmjow struggles to hold him back, Ichigo unleashes a point-blank Getsuga Tenshō that envelops Grimmjow in a surging, crackling, and enormous blast of Reiatsu. Grimmjow emerges from the blast alive, but bleeding profusely across his body, as he realizes this was not just Shinigami power and demands to know how Ichigo accomplished this in just a month.

However, Ichigo merely fires another Getsuga Tenshō at Grimmjow, who struggles to block it with his Zanpakutō, and moves behind the latter before reiterating that he does not have time to explain and firing a third Getsuga Tenshō at Grimmjow's back, trapping him between the two blasts. Falling out of the sky with further injuries as Ichigo follows him, Grimmjow angrily fires a Cero from his palm, forcing Ichigo to block it with his sword, and reappears behind Ichigo with Sonído to attack him when Ichigo succeeds in dispersing the blast, resulting in Ichigo blocking this strike with a blade lock and asserting that it is over.

Suddenly, Ichigo's mask shatters and falls off his face, prompting a startled Grimmjow to grin manically and affirm this as he sends Ichigo flying with a slash. Cursing his Hollow mask shattering at the worst possible time, Ichigo falls through the air prior to Grimmjow moving down to him with Sonído and slashing again with his Zanpakutō, forcing Ichigo to block with the sword of Tensa Zangetsu while Grimmjow observes that he seems to have used up all of his power since he began panting the second his mask came off. Though he admits that he has been injured pretty badly, Grimmjow concludes that it is over and mocks Ichigo for being unable to beat him even with Ichigo's new power. Ichigo is slashed across the chest again by Grimmjow and crashes into the ground with enough force to crater it, where he comes to a stop after rolling across the concrete and sees Grimmjow approaching him.

When Ichigo attempts to resummon his Hollow mask, the accumulated matter around his face abruptly disperses, causing a grinning Grimmjow to kick him hard in the chest and send Ichigo hurtling down the street past several houses. Initially assuming that Ichigo's mask cannot materialize again once it is broken, Grimmjow realizes that this cannot be the case since Ichigo attempted to restore it and theorizes that Ichigo has sustained too much damage, expended too much Reiryoku, or reached a limit for the number of times he can use it. After pinning Ichigo's sword arm to the ground by stabbing his own Zanpakutō through its wrist, Grimmjow concludes that Ichigo's mask is gone now no matter what the reason is.

However, as Grimmjow prepares to fire a Cero from his palm, which he assures Ichigo will blow his head off painlessly at this range, his hand and his lower legs are swiftly encased in ice, dispersing the charging Cero, and he turns to see Rukia Kuchiki standing with her Shikai, Sode no Shirayuki, right before she performs Tsugi no mai, Hakuren, engulfing Grimmjow in a wave of icy air. In the aftermath, Rukia kneels before Ichigo next to Grimmjow, who has been encased in a large and jagged block of ice, and begins attempting to pull Grimmjow's Zanpakutō out of Ichigo's wrist, where she rebuffs Ichigo's question about when she got here by asserting that she needs to concentrate since the Zanpakutō is stuck tight in the ground.

With Rukia sarcastically pointing out how useful the power that Ichigo used must have been given his current state and Ichigo telling her to shut up, Grimmjow abruptly breaks out of the ice and grabs Rukia by the head while inquiring about whether she believed that she could defeat him by simply freezing the top layer of his skin before charging another Cero against her head, causing a terrified Ichigo to struggle to free himself from Grimmjow's Zanpakutō before Grimmjow's arm is suddenly hit with enough force to push it off of Rukia's head, causing the Cero to fire and explode several meters away instead.

While Grimmjow stares in bewilderment at this, Shinji stands on a nearby rooftop and complains about having to get involved in a Shinigami battle, though he notes that he cannot exactly ignore it when they are making a ruckus so close to him. When Grimmjow questions what Shinji is and whether he is with Ichigo and Rukia, Shinji wonders why he would be, and when Grimmjow inquires about what he is, Shinji responds by raising the question of why it matters to Grimmjow, who concedes that he does not really care because he does not need to know who Shinji is in order to kill him and pulls his Zanpakutō out of Ichigo's wrist, which spurts a large amount of blood.

Grimmjow leaps toward Shinji and furiously attacks him, which destroys part of the roof Shinji was standing on. In response, Shinji reappears in the air behind Grimmjow and criticizes him for not having any control since his dodged attacks always destroy something and make Shinji think twice about dodging them to begin with, but Grimmjow merely scoffs at Shinji's belief that he is dodging the attacks and moves in to attack him once more. However, Shinji calls him a hothead and dons his own Hollow mask, shocking Grimmjow, prior to leaping forward and clashing with Grimmjow, who infers from his mask that he is associated with Ichigo, only for an annoyed Shinji to reiterate that it does not matter who he is and send Grimmjow flying several meters back with an explosive burst of force.

Following this, Grimmjow is astonished to see Shinji charging a Cero in front of his sword hand as the latter apologizes for not holding back since Grimmjow seems strong and fires the Cero at him, engulfing Grimmjow in a powerful explosion. In the aftermath, a further wounded Grimmjow crashes into the ground below and pants heavily while Shinji lands and praises him for mitigating the damage from the Cero by countering it with his own at the last second.

Aftermath
Suddenly, an enraged Grimmjow attempts to activate his Resurrección, but is stopped after he utters its release command by Ulquiorra, who grabs his sword hand and informs a stunned Grimmjow that they are returning because their mission has been accomplished before a Negación beam engulfs them from the sky above, which Ichigo recognizes. Ulquiorra notices traces of Reiatsu from Ichigo's Hollow mask and realizes that he has acquired a new power, but dismisses it as utterly insignificant and coldly informs Ichigo that there is nothing he can do to change this outcome since the sun has already set and the day belongs to the Arrancar while the Garganta he and Grimmjow were pulled into closes behind him, leaving a panting Ichigo staring angrily at the empty air where they stood.

Later, Hachigen Ushōda holds an unconscious, bandaged Ichigo and explains that his power is closer to a regression of space than outright healing, which requires him to actively identify the subject he is regressing in order to activate it, and that the Reiatsu of both Ichigo and Grimmjow are currently mingling in Ichigo's wounds, meaning that he will need to stay far away from the Visored with their Hollow-like Reiatsu in order to make a full recovery, before telling Rukia that taking Ichigo home and putting him to bed is the best treatment he can recommend right now, which Rukia thanks him for.