Sōsuke Aizen

"The gaze into the sun." - Tite Kubo

is the former captain of the 5th Division in the Gotei 13; he later leaves Soul Society with his followers, Gin Ichimaru and Kaname Tōsen. His lieutenant was Momo Hinamori. He is the main antagonist of the series.

Appearance
In Hueco Mundo, Aizen is first seen wearing Arrancar clothes over his Shihakusho. Afterwards, but before his transformation, Aizen wore full clothing similar in style to the Arrancar.

Prior to his departure from Soul Society, he appeared as a mild-featured man with brown scholarly hair enhanced by square glasses. He wears the standard Shinigami uniform with a captain's haori. However, during his ascent to Hueco Mundo, he removed his glasses and swept a hand through his hair, revealing menacing eyes and a very different hairstyle (swept back hair, with a strand hanging in his face). As he had previously revealed to Renji Abarai, the Aizen they all knew never existed and this would seem to be a visual representation of that claim.

Personality
Despite his current villainous status and former position of authority, Aizen is a surprisingly polite, soft-spoken intellectual, often addressing his subordinates by their given names. He rarely shows any sign of alarm or distress and often has entire situations planned out well in advance. Whenever confronted, Aizen is casual and uncaring, attempting to draw out a conversation and make small talk, which often infuriates the one he is talking to.

Aizen initially appeared to be a very kind, well-respected captain and was looked up to by many, especially his Lieutenant Momo Hinamori. However, this was just a mask to disguise his manipulative and very dangerous nature. In truth, he cares very little for his underlings (both past and present), and is willing to use almost everyone around him as pawns in his twisted game of chess. In his own words, Aizen claims to be unaffected by any form of morals or ethics as he views them as mere restriction on his potential. He is, therefore, willing to stop at nothing to further his selfish ambitions, including manipulating or killing anyone if he deems it to be necessary. He is fond of long, complicated, and somewhat convoluted plots, many of which do not have any real reason until he reveals them, and frequently appears to toy with his underlings for amusement. Unlike most of the other Shinigami who appear to have some kind of honor and kindness, including some Espada, Aizen lacks genuine compassion and honor.

During his time as a captain, he was known to like tofu, but he disliked boiled eggs. In his free time, he often read and he also gave a special lecture of calligraphy at the Shinigami Academy, given that he excelled in this branch of arts. This optional course was immensely popular among the Shinigami students, and many of them felt great sorrow at Aizen's sudden departure.

As the commander of his army of Arrancar, Aizen controls his new minions either through acquired respect or fear. Ulquiorra Cifer, one of his noticeably loyal subordinates, revealed in a conversation with Orihime Inoue that they are all here to further Aizen's ambitions. For more rowdy individuals like Grimmjow Jaegerjaquez, he keeps them in line through intimidation and mind games. The Arrancar Iceringer also claims that they follow Aizen because he has no fear, something which beings born from fear and despair find inspiring. Other Arrancar occasionally follow Aizen for reasons unique to themselves, such as Szayel Aporro Granz, who follows Aizen with the hopes that he will eradicate the world of all non-Hollows.

To date, the equally manipulative Gin Ichimaru is the only person who seems to be able to see through Aizen's manipulation. Ichimaru has also shown that he has some sense of Aizen's emotions and feelings, correctly identifying that Aizen was enjoying the invasion of Ichigo and his friends and their successes within Las Noches, as well as picking-up on the fact that Aizen had registered the arrival of Hinamori in battle of Fake Karakura Town and was surprised by it. By contrast, Kaname Tōsen has shown no such understanding and has fallen victim to one of Aizen's more minor mind games when Aizen off-handedly manipulated him into punishing Grimmjow for him while Aizen himself kept up his appearance of benevolence.

Aizen's true objective is to overthrow the king of the Soul Society. As he and his fellow traitor captains were departing from the Soul Society, he told Jūshirō Ukitake that "no one has stood on the top of the world", not even the gods, but he aspires to "stand in the heavens and end the unbearable vacancy on the world's throne". To do this, he needs the, a tri-pronged golden key that opens a portal to the dimension in which the Spirit King resides. While the location of the key is known only to Captain-Commander Yamamoto, Aizen knows how the original was created and how to manufacture another. To do this, 100,000 souls need to be gathered together (which will kill all the entities used) and vaporize a significant portion of the area used in its forging. His sights are therefore set on Karakura Town, which has an unusually large concentration of spirit particles.

According to Kisuke Urahara, since mastering the Hōgyoku, Aizen has become less cautious in battle; noting that before he subdued the device Aizen would not have allowed him to use level 90 Kidō. And Aizen admits that his new powers allow him to let his guard down. Also due to this newfound power, he has gotten more of a seemingly arrogant attitude, often not even thinking his attacks or defense through anymore like he used to.

History
At an unknown point in the past, Aizen is standing in a clearing with three other Shinigami who are kneeling before him. Gin Ichimaru spots him at a distance and recognizes Aizen as the leader. One of the Shinigami hands Aizen the Hōgyoku. Aizen puts the object in a glass and then hands it back to the Shinigami. As Gin spots Rangiku Matsumoto unconscious a short distance away, Aizen and his subordinates leave.

Approximately 110 years ago Aizen was seen making his way to the 5th Division living quarters of his captain, Shinji Hirako. He and Shinji had a discussion about style and trends before they made their way to the promotion ceremony being held at the 1st Division headquarters. As they got there, Aizen witnesses Hiyori Sarugaki attack his captain and the two got into a childish argument. He followed behind while the other captains congregate and have a brief discussion on the status of the Gotei 13. Overhearing Shunsui Kyōraku mention that the previous captain of the Squad 12 was promoted, Aizen interrupted and asked what Kyōraku meant by it. Aizen initially conjectures that the promotion was to Central 46. However, Shunsui explains that it had nothing to do with the Central 46 and that the previous Squad captain Hikifune had been accepted into the Zero Division also known as the Royal Guard. Aizen was left surprised at the revelation.

The following night, after Kisuke Urahara's appointment as the new captain of the 12th Division, Shinji had a short talk with him about his new role. While leaving Shinji asks, "How long do you plan on watching us from over there?" Using his hand, Shinji revealed Aizen concealed behind some form of camouflage. Aizen complimented his captain and asks him when he sensed him there, to which Shinji replies ever since he was in his mother's womb, and orders Aizen to follow. Aizen noted that won't do at all. Aizen then comments on how scary a person Shinji was, to which Shinji replies that Aizen was the scary one.

The very next night, Aizen saw Gin Ichimaru killing the 3rd seat of their division, and informs him that he was impressed by his skill. Aizen then asked him how he found the fight, to which Gin stated he found it pathetic.

9 years later, Shinji and Aizen were walking around the Seireitei when they came across Urahara, Hiyori and 3rd Seat Mayuri Kurotsuchi. While Shinji once again engaged in a childish fight and argument with Hiyori, Aizen asks Urahara if he had heard the news to which Urahara tells him he hasn't. Shinji proceeded to take up the tale and tells Urahara about the series of strange deaths that had taken place in Rukongai. Shinji also informed him that the 9th Division had been sent to handle the investigation.

With the disappearance of the 9th Division, captain-commander Yamamoto called an emergency meeting and assembled a team to investigate. After coming into contact with Hollowfied 9th Division members the investigation team was dispatched by an unseen assailant. Aizen was seen wandering around at night by captain Shunsui Kyōraku and some other Shinigami on guard, while the investigation team was still out searching.

It was later revealed that 9th Division 5th seat, Kaname Tōsen, was behind the betrayal of the 9th Division, having stabbed Kensei Muguruma in the back and killed Kasaki, Shinobu Eishima and Todō Gizaeimon, who had accompanied Kensei. He subsequently subdued the team sent to locate the missing 9th Division members using his Bankai. When captain Shinji Hirako of the 5th Division, asked him why he betrayed his captain, he was surprised to be answered by his own lieutenant Aizen, who stated that Tōsen didn't betray anyone and that he is, in fact, very loyal, and he just faithfully followed his orders.

Shinji admits he was not as surprised as he seemed to be, and Aizen asked if he suspected him, stating that he had expected that much from his captain. Shinji then explains how he had known something was dangerous about Aizen and that he couldn't be trusted. It was for those reasons that Shinji chose him to be his lieutenant, so that he could keep an eye on him. Aizen told him that he was grateful, as due to his deep seated doubts he didn't suspect a thing. When Shinji states that he already made it known that he had suspected him, Aizen elaborated stating that he didn't realize that for the whole past month, it wasn't him walking behind him. Aizen proceeded to explain the power of his Zanpakutō, Kyōka Suigetsu. Aizen informs Shinji that if he was as close to Aizen as other captains were to their lieutenants he would have been able to see through it by picking up on subtle differences between Aizen himself and Aizen's double. It was his lack of trust that kept them from getting close and as such, allowed Aizen to fool Shinji. He also explains that he could have always refused to be Shinji's lieutenant but decided against that action because his captain's suspiciousness made the position ideal to carry out his plans. Aizen thus laid the blame for Shinji and his comrades' current predicament at the feet of Shinji. Provoked by this, Shinji's anger triggered a speed-up in the Hollowfication process. Aizen thanked him for being so easily provoked and makes a note of the observed connection between Hollowfication and agitated emotions.

As he got ready to kill Shinji and the others, Kisuke Urahara and Tessai Tsukabishi arrived to stop Aizen from dispatching his captain. Aizen and Urahara had a brief discussion about what was transpiring, with Aizen acting innocent at first until Urahara notes that the investigation team doesn't have simple injuries, but were in fact going through Hollowfication. Aizen commended Urahara on his deduction and reveals himself to be behind the disappearances in the Rukongai. As Aizen had been engaging in early experiments on Shinigami/Hollow hybrids, which involved using an unknown device to cause spirits to transform into Hollows, he was responsible for turning his former captain and seven other Shinigami into Vizard, though Aizen refuses to go into any of those details.

Aizen proceeded to leave the scene of the crime with his henchmen, stating that "there's nothing more to do there". To stop them from retreating, Tessai performed Hadō #88. "Hiryugekizokushintenraiho" spell against them, only to be countered by Aizen using Bakudō #81. "Danku", allowing them to escape.

Some point after the Hollowfication incident, Aizen became Captain of the 5th Division and made Gin his lieutenant. Aizen continued to experiment on Hollows and while testing out a new breed of Menos Hollows capable of concealing their reiatsu, Aizen’s interest was piqued by the then first years Momo Hinamori, Izuru Kira, and Renji Abarai. Realizing their potential, Aizen took them all into his division. While the obedient and loyal Kira and Hinamori became the lieutenants of the 3rd and 5th Divisions under Gin and Aizen, respectively, Renji proved to be too rebellious and was transferred to the 11th Division (later transferring to the 6th to become that squad's lieutenant).

Gin and Tōsen later became captains of the 3rd and 9th Divisions, respectively, but remained loyal only to Aizen. According to Aizen, even when Hinamori was his lieutenant, he always thought of Gin as his subordinate.

At some point during their captaincy Aizen, Gin and Tōsen, secretly visit Baraggan Luisenbarn, King of Hueco Mundo and Lord of Los Noches. He and Baraggan engaged in a light conversation and he asked Baraggan to look at his Zanpakutō, he then asked Baraggan if he was happy in his position and if he would join him in a new world where he will be granted more power. Baraggan dismissed this notion stating that there was no power higher than his. Aizen then releases his Shikai and showed Baraggan the decimation of his army and subjugating him in turn. Baraggan promises to seek Aizen's destruction for all eternity.

About fifteen years ago, Aizen had become aware of the birth of Ichigo Kurosaki. Understanding the significance of his birth, he had decided to aid his development for his plans. To this end, he had Rukia Kuchiki stationed in Karakura Town. He also put into place obstacles that would force Ichigo to grow stronger, including the Hollow that attacked his family and the Menos Grande that appeared when Uryū Ishida used the Hollow bait.

Soul Society arc
When Rukia Kuchiki is brought back to Soul Society with the Hōgyoku concealed within her body, Aizen quickly manipulates everyone into an elaborate conspiracy. Aizen first kills all the members of the Central 46 Chambers and begins moving Rukia's execution date up. He then begins to plant suspicion within Soul Society, initially speaking of the possibility of a conspiracy with Renji Abarai (without explicitly saying he was behind it) and tries to use Gin's intrusion in repelling Ichigo Kurosaki and the Ryoka to orchestrate suspicion among the gathered captains, particularly Tōshirō Hitsugaya, who witnessed the conversation personally. He later uses his Zanpakutō's ability to trick everyone into believing that he has been killed and has Gin leading everyone to believe Gin himself is the murderer.

He also sets up his lieutenant, Hinamori, to believe that he was likely killed by Hitsugaya, her childhood friend, to get her out of the way. Because of the nature of Rukia's sentence and execution method, the Gotei 13 splits into factions and the captains begin to fight amongst themselves. During the turmoil, Gin executes the overt aspects of the plan, which begins to be revealed when 4th Division Captain Retsu Unohana begins to suspect that there is something wrong with Aizen's supposedly dead body.

Aizen reveals himself by nearly killing his lieutenant and defeating Hitsugaya. He is however suddenly stopped by Unohana who has figured out something was wrong with his corpse doll, only for Aizen to reveal his corpse doll and disclose to Unohana and her lieutenant Isane Kotetsu the true abilities of his Zanpakutō. This leaves Unohana to deduce the ritual for being affected by the hypnosis, after which Aizen reveals that because of this Kaname Tōsen has always been his subordinate. Aizen then has Gin bring the two of them to Sōkyoku Hill where Tōsen had brought Renji and Rukia to him.

There he gently orders Renji to put Rukia down. As Renji refuses, he comments on Renji's stubbornness, and says that, in deference to Renji's feelings, it is acceptable if he wants to hold on to her but that he'll have to just leave the arms he's holding her with behind. Aizen then draws his sword and attacks Renji, but Renji is able to draw his sword in time to dodge Aizen's attack leaving only his right arm damaged. Aizen applauds his ability to dodge and expresses happiness with the improvements in his skill since he was one of Aizen's subordinates. Aizen tells Renji that he doesn't want things to be harder, because he finds it difficult to hold back his strength. He states that as Renji's former superior officer that he finds it unbearable for a subordinate to die. As Renji challenges the assertion, and asks Aizen why he killed Hinamori. Aizen explains that it was an act of compassion, seeing as he'd trained Momo so that she could not live without him. Renji says that Aizen is not the captain he knew, and Aizen states that he was the same man, but that neither Renji nor anyone else had realized what he was. As Renji attacks with his Shikai, Aizen blocks it with his bare hand and easily cuts the segments of the blade apart while also cutting up Renji. Since Renji still refuses to give up Rukia, Aizen prepares to kill him, only to be stopped by Ichigo.

Ichigo teams up with Renji, but even after using Renji's strongest attack with his Shikai to create an opening for Ichigo the attack fails. Aizen displays his prowess by effortlessly disposing of them, first by blocking Ichigo's blade with a single finger and nearly cutting him in half. He then begins to drag Rukia off, while explaining his plans to the critically injured but still conscious Ichigo. He critically injures the 7th Division Captain Sajin Komamura with a level 90 Kidō spell as Komamura attacks him. Afterward, Aizen removes the Hōgyoku from Rukia's body by using information from research by Kisuke Urahara hidden in the chambers of Central 46.

Surprised that the procedure didn't kill her, and having no further use for her, he orders Gin to kill Rukia as he prepares to leave. However Byakuya Kuchiki saves Rukia by taking the blow. Aizen turns around and is about to draw his Zanpakutō in order to finish her himself, but is suddenly blocked by Yoruichi Shihōin. He is threatened with death from Soifon's Zanpakutō if he so much as moves. He calls Yoruichi a nostalgic face but he still appears confident. Aizen then notes how not even Yoruichi and Soifon will be able to come after him while fighting them. Kūkaku Shiba and Jidanbō arrive to assist. Gin is suddenly restrained by Rangiku Matsumoto, prompting him to apologize for being unable to help Aizen. They are suddenly all surrounded by every captain and lieutenant of the Gotei 13 still capable of moving. However Aizen just smiles and says that it is time. Realizing something is wrong Yoruichi yells for Soifon to get away, and runs away herself just in time. Aizen is suddenly bathed in light along with Gin and Tōsen and Genryūsai Shigekuni Yamamoto calls the others off. He explains that Aizen, Tōsen, and Gin were completely untouchable the moment they were covered in that light, called a Negación, a separate world created by Menos Grande when rescuing one of their own, to transport them to Hueco Mundo.

While leaving, Aizen removes his glasses and change his hair style by combing a hand through it. His glasses evaporate into dust. He then proceeds to announce his goal to stand atop of the world in the heavens and take the place of the absent gods, something no one has ever done before. Before finally ascending into the portal created by the menos arrival, he bids farewell to all of the shinigami present and then tells Ichigo that he was very interesting for a human.

Arrancar arc
From there, Aizen changes his clothing style to resemble that of the Arrancar, and begins to create several Arrancar. At some point he also finds Coyote Starrk and Lilynette Gingerback and is impressed with the Arrancar. He asks if the mountains of Hollows were killed by him and Starrk tells him that they just died. He then makes an offer to Starrk to join him as an ally. Starrk believes Aizen to be strong and agrees to join him. He eventually sends Grand Fisher and two other strong-leveled Hollows to the living world. Grand Fisher is killed by Isshin Kurosaki and the other two are killed by Ryūken Ishida. Isshin and Urahara contemplate that Aizen sent these pseudo-Arrancar to Earth to look for information on Ichigo.

Later, he sends Ulquiorra Cifer and Yammy Riyalgo to find Ichigo and report on his progress. They almost kill Tatsuki, Chad, and Orihime, and Yammy manages to kill a square radius of people in the park. After the mission is completed, Ulquiorra and Yammy head to a meeting consisting of Aizen and 20 other Arrancar (including fellow Espada members Grimmjow Jaegerjaquez and Tia Harribel). Ulquiorra, who can crush his left eye, uses the dust from it to show what he has seen himself to the others and Aizen. Grimmjow, Shawlong, and Di Roy question Ulquiorra and Yammy on why they just did not kill them as ordered, though Ulquiorra claims that Ichigo does not pose much of a threat to Aizen or the Espada. Grimmjow and his Fracción (Shawlong, Edrad, Nakeem, Yylfordt, and Di Roy) later invade Karakura Town without orders, causing Kaname Tōsen to travel there and bring back Grimmjow (his Fracción were killed during their unauthorized mission) and punishes Grimmjow himself, when Aizen refuses to take action.

Later, after examining Orihime Inoue's powers, Aizen decides to initiate another invasion on Karakura Town, letting Ulquiorra hand-pick the invasion force; though Aizen personally sends Grimmjow as well. Ulquiorra, Grimmjow, Yammy, Luppi, and Wonderweiss Margera go to invade Karakura Town to capture Orihime. . Ulquiorra succeeds in forcing Orihime to join Aizen's side and brings her to Las Noches, where he has her display her power by restoring Grimmjow's amputated left arm, explaining to the Arrancar present that Orihime's powers are rejection, meaning she is able to "reject" anything that has happened. Orihime also restores Grimmjow's Espada tattoo (at Grimmjow's request). Grimmjow immediately kills his replacement, Luppi, with his newly restored arm.

Hueco Mundo arc
Aizen calls the Espada to a meeting and invites them to have some tea. As they are having their tea, Aizen reveals to them the presence of Ichigo, Ishida and Chad. When the Esapda start to dismiss them off-hand, he warns them not to underestimate the trio, revealing to them their exploits in Soul Society and identifying Orihime as the missing the member of their little group, whom the others have come to rescue. At this point, Grimmjow begins to leaves, stating that he is going to go eradicate the threat in Aizen's name. However, Aizen stops him and resorts to intimidating Grimmjow with his Reiatsu pressure when the latter hesitates to back down, bringing Grimmjow to his knees. He then tells the other Espada to return to their palaces and wait patiently. Telling them not to be overconfident but not to be afraid either because as long as they are with him, no one can defeat them.

At some point, Aizen has Orihime brought to his room by Loly Aivirrne and Menoly Mallia. After sending the two Arrancar away, Aizen shows Orihime the Hōgyoku. He asks her to interpret him showing her the Hōgyoku as a sign of his trust in her and asks her to use her power of event rejection to undo some minor damage that has occurred to the Hōgyoku from being repeatedly reawakened.

Following the arrival of Ichigo and company to Las Noches itself, Aizen is brought the news of Dordonii Alessandro Del Socacchio demise by a messenger. Aizen is unsurprised by Dordonii's demise but expresses surprise that Ichigo struggled against him. He then corners the messenger by catching him a lie of omission and demands to know from the messenger, who sent the Exequias after Dordonii. The messenger does not answer but Szayel Aporro Granz intervenes and reveals that it was him. Szayel begs Aizen's forgiveness, which Aizen grants him but as Szayel turns to leave, tells him to make his reports more through next time. This shocks Szayel, as Aizen goes on to ask him if the Reiatsu record he obtained from Dordonii will aid in his research. Szayel replies in the affirmative and leaves. Following his departure Ichimaru, who had been present in with Aizen the entire time, asks Aizen if he is enjoying himself even though his subordinates are losing. Aizen confesses that the emotion he is feeling at the moment is akin to enjoyment.

After the Espada no. 9 through to no. 5 are defeated by Ichigo, his friends and the invading Shinigami Captains, Aizen has Starrk bring Orihime to him. He tells Orihime to smile and tells her to wait where she is while they go and destroy Karakura Town. He orders Tōsen to cast the Tenteikūra spell and using that he reveals to all his true motivation behind the capture of Orihime. By kidnapping her, he inspires Ichigo and his friends to attempt a rescue, thereby depriving Soul Society of a valuable military asset. Furthermore, when four captains assist in her rescue, adding to the three that have already defected, Soul Society is left at half its regular strength. Thus, he and his forces are now ready to mount their challenge and he leaves with Gin, Tōsen and Espada no. 3 through to no. 1 to invade Karakura Town, leaving Las Noches in the hands of Ulquiorra.

Fake Karakura Town arc
As he leaves to destroy Karakura Town, he seals the portals the intruders used to access Hueco Mundo, effectively stranding them there until his return and leaves Ulquiorra in charge of Las Noches. Though Soul Society is able to substitute the town for an abandoned facsimile, Aizen only muses that he will have to travel to Soul Society to destroy the real town after he and his forces (Ichimaru, Tōsen, the top three Espada and their Fracción) defeat the remaining captains. Before his group is able to take action, Aizen is trapped in Yamamoto's fire prison with Ichimaru and Tōsen and is unable to fight. Nevertheless, he claims that such action will be unnecessary, for that the power of his Espada alone will be enough to defeat the Gotei 13.

When Hinamori arrives in the Fake Karakura Town to assist Matsumoto, he has a somewhat intrigued look in his eyes upon sensing that his former lieutenant, whom he assumed he killed, was alive. When Gin asks him if anything is wrong, Aizen calmly states that Hinamori's presence won't make any difference.

Fūrā arrives in the Fake Karakura Town alongside Wonderweiss Margera and blows out the fire prison where Yamamoto had encased Aizen, Gin and Tōsen in. Aizen comments that the smell of death is splendid as he walks free with his two comrades, believing the smell fits the occasion. Everyone is alerted to his presence, which noticeably scares Izuru Kira, who fears that Soul Society may have lost. However, the Vizard arrive and after a short battle against a group of Gillians, Shinji Hirako confronts Aizen. Shinji attempts to slash at Aizen, but is then stopped by Kaname Tōsen as Aizen looks on.

As the battle continues and as Baraggan comes close to his death, he launches his blade at Aizen in a desperate attempt to kill the person responsible for him losing his position as King of Hueco Mundo. But his own Respira destroys the axe before it can even reach Aizen, who simply looks away. Both Stark and Harribel notice this, and the former even comments on the fact that Aizen has nothing to say at the Segunda's passing.

Aizen observes Starrk's defeat as the Primera Espada falls to the ground and subsequently takes notice of the fight between Tia Harribel and Hiyori Sarugaki, Lisa Yadōmaru and Tōshirō Hitsugaya. He stops the fight between Gin and Shinji, telling Gin that was enough and states that it is time to end this fight. Using Shunpo, he appears near Harribel's battle, surprising her. He slashes her straight across her torso with his Zanpakutō, dealing her a serious wound. Her face shows surprise as he tells her that it appears that she is not strong enough to fight for him. After this, he tells Gin and Kaname that it's time to go.

Aizen laments to Harribel that after all the trouble he went through gathering the Espada, that he alone would be more powerful than all of them. Harribel looks at him with rage and stabs her sword into his chest, impaling him. Aizen's expression does not change as he says dealing with her is such a pain, surprising Harribel. She then realizes she attacked an illusion and that she has been stabbed in her back in her left shoulder by Aizen. He then tells her he will never let her raise her sword to him again, to which he withdraws his sword as she falls to the city below. Aizen then tells everyone to come at him, calling out the Gotei 13 and the Vizards.

As Shinji warns the Vizard, especially Hiyori, to not approach Aizen carelessly, Aizen begins to taunt them, telling them that it doesn't matter if they approach him cautiously or not at all as the outcome would be the same. He also tells them that they have nothing to fear because they have already died that night 100 years ago. This taunt sends Hiyori over the edge and she charges him, only to be bifurcated by Gin Ichimaru. Shinji goes to her side and stares down Aizen in anger. Aizen comments that he likes the look in Shinji's eyes, as he looks like he has finally awakened after 100 years sleep. Aizen then taunts him and tells him to face him, as he will unsheathe his sword especially for him. Shinji, after calling to Hachi to take care of Hiyori or at least keep her safe until Ichigo returns, approaches his former lieutenant to engage him in battle. Aizen asks why he would put his faith in that boy. Shinji simply tells him that he doesn't expect him to understand as he doesn't even trust his own followers. Aizen then explains that trusting someone means relying on them and only the weak do that, therefore it is not something that they need. Shinji questions how he can say that with all the followers he has, as he is sure that Aizen has asked them to trust him.

Aizen corrects him stating that he is wrong as he never asked them to trust him at all. He told them to come with him, but he has never told them to trust him. In fact, Aizen has always told them not to trust anyone including him, though he sadly laments that there are not many strong enough to do that. Aizen further explains that "All creatures want to believe in something bigger them themselves. They cannot live without blind obedience. And to escape the pressure of that trust, those in whom faith is placed in turn look for someone higher them themselves. And then those people in turn look for someone even stronger. That is how all kings are born. That is how all Gods are born. But make no mistake. They all still abide to me. Because from this point onward, you will witness firsthand the power of the god they foolishly placed their faith in. I will become that god they have no choice but to believe in." Shinji comments on Aizen drawing his blade, somewhat surprised that he would do so at all. He then asks Aizen if he is scared, but Aizen remains silent. Shinji then states that there is no point in ignoring him, as no matter how strong he is that he still has to be uneasy. He then quotes Aizen's own words from 100 years ago, about how Shinji had never opened up to him, never told him anything or even tried to get to know him. He then tells Aizen that because of that he doesn't have a clue what kind of powers his Zanpakutō has. Shinji states to Aizen that if he thought that his Kyōka Suigetsu was the only Zanpakutō with the ability to absolutely control other people's senses, he was dead wrong. He then releases his Zanpakutō.

The release of Shinji's Shikai prompts Aizen to comment that it's an interesting shape for a katana. Shinji responds that it is great, but he will not lend it to him. Aizen then states that he finds it strange that it does not give off any particular kind of aura. So he questions if he has heard wrong about it being able to control the five senses. Shinji tells him to take another look as it is already changing, as he casually asks if it has a nice scent. Aizen realizes that something has transpired but Shinji tells him it is too late and welcomes him to the inverted world. Much to Aizen's surprise, he now appears as though he is standing upside down in mid air, Aizen notices the possible change in directions. Shinji explains that Aizen's senses have been inverted and moves to attack him while Aizen comments that the ability is interesting, as it causes everything to be opposite. Shinji appears to be surprised when Aizen figures out that forward and backward are opposites as well as he turns around to block Shinji's attack, asking his former captain if he really thought that it would fool him. But Aizen is again surprised as his left arm is cut, Shinji explains that even his eyesight and where he gets cut is reversed as well.

He then states that no matter how powerful he is or what Aizen tries, his body will always fight by reflex and fall to Sakanade's ability. Shinji goes to attack Aizen again but misses, while Aizen states that he was trying to figure out what it was and now he sees it is nothing more than an optical illusion. Shinji then realizes he has been cut across his back as he passed by Aizen, which surprises him. Aizen then states that by controlling all five senses Shinji cannot even begin to compare to his powers. He then notes once one gets used to it, there is no problem as he taunts Shinji, telling him that it was mere child's play. Moments later, he looks down as Sajin Komamura yells up at him. Suddenly, the sky begins to crack and Ichigo Kurosaki breaks through, battle ready, right behind Aizen. Ichigo tries to strike at the back of Aizen's neck with Getsuga Tenshō, but it hits a barrier. As the explosion of power clears, Aizen greets Ichigo, telling him that while it was a good slash, the spot he picked was not good. He states that it would be ludicrous to think he would enter battle without putting some sort of defense behind the neck, which he says is the biggest blind spot for all living creatures. While Ichigo ponders what he should have done, Aizen guesses Ichigo's thoughts that he should have used his Hollowfication and mocks him. He invites the substitute Shinigami to try again and come at him Hollowfied and that he will show Ichigo how conceited those thoughts are.

Ichigo uses Hollowfication and releases another Getsuga Tenshō, but Aizen evades it and appears behind Ichigo. Ichigo quickly moves away from Aizen again, causing Aizen to ask why Ichigo is keeping his distance. Aizen tells him that distance only has meaning in a battle between equals, but that between him and Ichigo, distance is meaningless and that he can always touch Ichigo's heart. As he says this, he flash steps right in front of Ichigo and lays his fingers on his chest. A highly surprised Ichigo attempts to attack again, but Aizen evades. Aizen questions why he is fighting him, and whether or not Ichigo hates him. Aizen tells Ichigo that by just by looking at his face, he can tell that Orihime Inoue and Ichigo's other friends have not died, giving him no real reason for Ichigo to hate Aizen and therefore lacks the necessary drive to defeat him. Aizen explains that he is just brandishing his sword out of a sense of responsibility to the other Shinigami. However, Aizen tells him that that is not enough and that a fighting spirit without hatred is an eagle without wings. Aizen goes on to tell Ichigo that powerless comrades cannot be anything but weights that break your legs. Ichigo begins to waiver, but Komamura appears beside him and tells Ichigo not to be disheartened and that provoking his opponents is Aizen's forte. He and the other Shinigami and Vizard prepare to help Ichigo fight Aizen while avoiding becoming influenced by his Shikai

As Hitsugaya starts the attack, Aizen mocks him for being impatient, to which the young captain responds that someone has to start the fight. Shunsui then launches a second attack, but hits another of Aizen's barriers instead. Hitsugaya states that Aizen's earlier comment that one who strikes without anger does not belong in the battlefield is wrong. He states that one who strikes solely out of anger is not a true warrior; that a captain's only true reason for combat should be for duty. Tōshirō says that it is clear that Aizen never deserved to be called a captain, to which Aizen merely smirks. He then counter's Hitsugaya's statement by pointing out that Hitsugaya still holds anger at Aizen for what he did to Hinamori. This prompts Hitsugaya to admit he is also motivated by anger and releases his Bankai. Upon releasing his Bankai, Hitsugaya declares his unyielding hate towards him and proclaims he would gladly relinquish his seat as a captain if he could just kill him. As he is engaged by Hitsugaya, Aizen effortlessly dodges every attack made upon him by the young captain.

As he prepares to counterattack, Kommamura attacks his front as Love attacks his back. A barrier breaks Kommamura’s blade and Aizen releases his spiritual pressure to teach him a lesson. Komamura then releases his Bankai and attempts another attack, but fails as Aizen casually slashes through his Bankai, cutting off its hand and Komamura's in the process. Kommamura fails again as Rose tries to attack Aizen only to be pulled towards him and slashed, sending him to the ground. Aizen wraps Rose's Kinshara around Love, pulling him closer and slashes him as well. Lisa then attacks but only manages to get her blade broken. Aizen then asks that if he can have Arrancar obeying him, how do they, as what he calls "pseudo-Arrancar", expect to stand against them.

Soifon then Flash Steps in front of Aizen. He states that she is mad and wonders what the captain-commander must be thinking, sending in the Onmitsukidō. He recites a mantra learned at the Shinō Academy about striking from behind. Soifon smiles and asks how a traitor such as him can speak of such things and tells him that it makes her laugh. Aizen points out he was a teacher, to which Soifon states that the Central 46 must have been joking to make him a teacher, and that it is no wonder he had them fooled. Aizen tells her not to speak ill of the dead and notes that he had them all fooled as well. Soifon remarks that she is shocked if he actually thinks he can fool her. She then makes several clones of herself using Shunpo, which impresses Aizen. Soifon states that she will take that as a compliment as they do not get much praise in the Onmitsukidō, and she thanks him. Then all her clones move to finish Aizen off.

Aizen moves to take out his Zanpakutō, but his sword and arm are immediately encased in ice much to his surprise. Before he can react, Soifon stabs him the in the chest with her Nigeki Kessatsu technique. Aizen notes that it is an interesting technique but it cannot harm him. Surprising Soifon, he explains that a battle between Shinigami is a battle of Reiatsu, and that his reiatsu will crush her attacks and powers. Aizen is then surprised as he is attacked from the back by a shadow. Shunsui reveals himself having used his Kageoni technique, stating Aizen was careless by not taking into consideration that there was a shadow on the ice. As Aizen curses the 8th division captain under his breath, Hitsugaya tells Aizen it's over. Aizen glances at him as Hitsugaya rushes at him, noting to himself that because Hitsugaya is so young, he attacks at the first opening without planning ahead, calling it his biggest failing. Just then he notices Shinji holding ‘’’Sakanade’’’ and realizes it is too late to react since he is in the inverted world.

However, the Aizen before the captains' eyes is only an illusion. He had used Kyōka Suigetsu to cast his illusion on the others and switched places with his former lieutenant, Hinamori. The real Aizen was lying down next to Kira and Iba. Ichigo, being the only one who has not yet seen Aizen's Shikai, sees through the hypnosis and shouts at the captains, causing them to realize the deception. After his illusion is revealed, he walks up from the ground. Kira and Iba, believing that it is Hinamori walking away, try to follow him but are cut down with a simple slash. Shinji, angered at the deception, yells at Aizen, asking him when he cast the illusion. Aizen simply asks when they started thinking he was not using Kyōka Suigetsu, also stating that Kyōka Suigetsu can create an illusion out of any situation. Hitsugaya, overcome with anger at being fooled by Aizen into attacking Hinamori, bellows in rage and charges at Aizen, even with Kyōraku warning him to wait. Aizen tells them that they are all completely open and dispatches the four captains with ease.

As he acknowledges the fallen warriors' strength to survive such a blow, he decides to let them live to see the end. After the last combatants are defeated by Aizen, Yamamoto makes his presence known by drawing Aizen's attention with a huge pillar of fire. Aizen states that although he has finally shown himself he is too late, as of now he is the only one left to be counted as manpower. Aizen notes that if he falls, the Gotei 13 will crumble. He explains that waiting on the sidelines, Yamamoto has lost his chance. Yamamoto asks Aizen if he really thinks he can cut him down with that much power. Aizen responds that he doesn't have to cut him down, as he already has. Yamamoto becomes enraged and before he can react Aizen appears behind as the captain-commander turns to face him, Aizen stabs him through his stomach with his Zanpakutō. Yamamoto grabs Aizen's arm pulling him in closer and exclaims that he has caught him. When Aizen tries to trick him into questioning whether or not he has caught the real Aizen, the captain-commander calls his bluff and says he can sense the Reiatsu coming from the blade in his stomach.

Yamamoto then reveals that he has laid a trap for Aizen, and initiates his Ennetsu Jigoku technique, saying that everything was a trap so that he could die in the flames with Aizen. He then screams to Ichigo to get back as he is not of the Gotei 13 and he should not have to endure their fate. When Aizen asks if he would really risk killing the other combatants to try and destroy him. Yamamoto states they are all prepared to die to destroy evil and that is the true spirit of the Gotei 13. A released Wonderweiss Margera then appears behind Yamamoto, and sends him crashing to the ground below. Aizen explains that he knows full well that Ryūjin Jakka is the strongest Zanpakutō and that in a one on one battle Yamamoto's strength far outweighs his own. He reveals that Wonderweiss is the only modified Arrancar in existence and that his Resurrección, Extinguir, is built solely for the purpose of stopping his Ryūjin Jakka. Despite this action, Yamamoto remains unfazed, quickly switching to hand-to-hand combat, effortlessly pushing Wonderweiss away and through a building.

Yamamoto reminds Aizen that he has been the Captain-Commander for over a thousand years because of his unrivaled might. He then attempts to punch Aizen in the face, only to have Wonderweiss with a gaping hole in his stomach, pull him away. Aizen then calmly watches as Wonderweiss engages the old captain. When Yamamoto effortlessly destroys Wonderweiss with a single double-fist attack, he turns his attention to Aizen, mocking him for modifying Wonderweiss. Aizen counters by saying that he merely gave purpose to one who only exists to feed on souls and reminds Yamamoto that Wonderweiss was made to seal away the power of Ryūjin Jakka, including the flames that were produced before Wonderweiss began attacking the captain-commander. Realizing what Aizen was talking about, Yamamoto acts quickly to shield Karakura Town with his body from the explosion of flames released from Wonderweiss's remains. As Aizen approaches a battered Yamamoto, he commends the old captain for realizing the truth and acting in time, taking out his blade to finish off Yamamoto. The captain-commander, however, calls Aizen naive and, grabbing his ankle, and uses Hadō #96, Ittō Kasō.

Aizen notices that Yamamoto's burnt arm is cracked and recognizes the Kidō as Ittō Kasō, a sacrificial spell. Aizen admits to himself that he underestimated the captain-commander. He escapes from the flames with slight burns, only to be surprised when he realizes that a Hollowfied Ichigo is pouncing on him. Ichigo launches a Getsuga Tenshō at him, sending him crashing through a building and wounding his shoulder. As Ichigo continues his attack, Aizen blocks his blade and tells him that he has missed his chance to kill him, as he will not present any more openings. Ichigo points out that he has injured Aizen, but the wound closes up. Aizen reveals that he has placed thHōgyoku in his chest which instinctively heals its master. Aizen compliments Ichigo's Reiatsu, saying that he has grown, just as he had planned, surprising Ichigo. He then lists various important occurrences in Ichigo’s development and claims they all happened as he desired.

When Ichigo angrily asks what he means by this, Aizen tells him not to raise his voice and questions why the substitute Shinigami is so surprised. Aizen explains that he helped him grow because he believed that Ichigo would be the perfect subject for his research. Aizen then asks Ichigo if he thought certain events to only be coincidences, prompting Ichigo to attack Aizen again. The renegade captain, however, blocks the attack and then grabs Tensa Zangetsu with his hand as Ichigo swings again. Ichigo says he does not believe Aizen due to what he said when they first met. Aizen claims he did not tell the truth during his defection. Aizen goes on to list a few more happenings that he had planned. When Aizen questions the belief that he did not know the location of the Hōgyoku for the past hundred years, Ichigo asks him when he came to the conclusion that he would be the perfect subject for his research. Aizen replies that he has known about Ichigo from the day he was born. Before he can elaborate on this, he is interrupted by Isshin Kurosaki, who appears on the battlefield between his son and Aizen, stating that Aizen "said too much". Isshin immediately sends Ichigo off in the distance and Aizen comments that that was a smart move. Aizen asks Gin how long he has been watching to which Gin responds he did not see an opportunity to help. Isshin then attacks Aizen and sends Aizen crashing through multiple buildings. Their battle continues as Isshin begins to notice Aizen tiring, to which Aizen responds that he has reached the limit of his Shinigami self and that the Hōgyoku has begun to understand his desires. He then goes on to say that the Hōgyoku possesses a will of its own and that he only became aware of this after becoming its master. He explains that the true power of the Hōgyoku is not the removal of the boundaries between Shinigami and Hollow, but to capture and materialize the hearts around it. He claims that it has brought about the "miracles" surrounding Ichigo, Rukia and Kisuke Urahara. He continues to explain that Kisuke misunderstood the nature of the Hōgyoku because the breakdown of the barrier between Shinigami and Hollow was his own desire, which the Hōgyoku made real. He claims that Ichigo, Sado and Orihime all got their power from the Hōgyoku and that the Shinji and the others were an experiment in Hollowfication and a test of the Hōgyoku’s power. Then, with a theory on how the Hōgyoku worked, he sent Rukia to Ichigo's side. He then explains the limits of the Hōgyoku before being interrupted by Gin knocking Ichigo into a nearby building. As Ichigo talks to Isshin, Gin asks Aizen if he interrupted his speech. Aizen replied that he had reached the end of his speech and his body is enveloped by the Hōgyoku. As he says the Hōgyoku deserves its name, Aizen is interrupted as he is shot from behind by Kisuke Urahara, whom he welcomes onto the battlefield.

Urahara mentions that it has been a long time since last they met and takes note of the extraordinary form Aizen has taken. Aizen states that its nothing as midway through "evolution" is always ugly. Urahara clarifies that no one has said he is ugly and notes that Aizen has fused with the Hōgyoku. Aizen explains that it is not fusion, saying that he subjugated the Hōgyoku, which Urahara had failed to master. Urahara glares down at Aizen and remarks that it is true he was unable to master it in the past. Aizen questions his statement, saying that he must be unable to admit defeat. He then retracts the question making note that it shouldn't be the question. He then uses and impales what he believes to be Urahara. Aizen then tells him that he has already forever lost the chance to command the Hōgyoku. Urahara's body then bursts like a balloon as Urahara appears behind Aizen and places his palm against his back as he uses Bakudō #61. Rikujōkōrō. Aizen notes that he has seen the use of the portable Gigai decoy tactic in Yammy's report. He admits he let his guard down as he never thought Urahara would use such a petty trick. He then enquires what Urahara will do now that he has been constricted with "this meager Bakudō". Urahara then asks how much it will take before it is not meager and follows up in quick secession with several other Bakudō. Urahara then begins an incantation with Aizen asking whether he really thinks he will let him use that Kidō spell, but Urahara tells him it is too late as he initiates '''Hadō #91. Senjū Kōten Taihō'''. After the smoke explosion dissipates Urahara remarks that Aizen has truly let down his guard because of his new found power Aizen deals Urahara a few blows and notes that the Hōgyoku has made him invincible and has no need to dodge. Urahara then states that he was not talking about dodging the Kidō, what he meant was that in the past Aizen would never have come into physical contact with him twice without a plan. Aizen is suddenly trapped by spiritual energy cuffs at his wrists. He stares in shock as Urahara explains that it is a seal, which blocks off the reiatsu vents located in the wrists of all Shinigami. He tells Aizen that he will be incinerated by his own reiatsu from the inside out, as Aizen is enveloped in a column of light.

Aizen notes that that seal would have worked had it been on anyone else. He then corrects himself stating had he not implanted the Hōgyoku in his body and subdued it the battle would have been over. He then reaches in through the covering of his wrist and pulls out a bracelet, stating that unfortunately for Urahara, the Hōgyoku he created was beyond his comprehension. Therefore, the technique Urahara most likely created solely for the battle with him was also incapable of reaching him. Urahara unsheathes his Zanpakutō prompting Aizen to ask him if since his techniques did not work, he now intends to use power against him. Isshin comes up from behind and Aizen attempts to attack them both at once but he is quickly blocked as they both simultaneously entangle his sword hand and one of his ankles and stretching him into an awkward position. Aizen demands to know what is going on as Yoruichi Shihōin, wearing armor on her arms and legs, attacks him from above. She smashes into his back with such force that it destroys the surrounding area and then she lands a direct punch with even more force, causing damage to an entire block. Urahara then yells for Yoruichi to move away. Aizen quickly recovers and before Yoruichi can fully dodge his counterattack he destroys the armor on Yoruichi's left leg. As Aizen emerges from the rubble with his new form severely cracked, his right wrist merging with his Zanpakutō, he asks them if this all they have. Stating that they better hurry up and make the next move as he plans on crushing them all one by one into tiny fragments down to the very last remnant. Challenging his opponents to attack him, Aizen gives Ichigo a cold stare to deter him from entering the fight. He then points out that there must have been something special about the armor Yoruichi is wearing for it to have allowed her to survive his attack without injury, stating that if that is the case, then he only need attack her three more times to destroy that "specialness". Aizen then suddenly appears next to Yoruichi and attacks, causing a large amount of destruction to the surrounding area.

Having shattered more of her armour, Aizen watches on as Yoruichi and Kisuke bicker again. When Kisuke asks why he is staring at him, Aizen explains that he was wondering if Kisuke was expressing concern for Yoruichi as part of a plan. When Kisuke retorts that Aizen was showing concern for the battle again, Aizen reveals that while he is now much stronger, he still finds Kisuke interesting as he is the only one in Soul Society who exceeds his intellect. Unconcerned by Aizen's words, Kisuke attacks Aizen with Hadō #32, Ōkasen. Aizen easily blocks it and anticipates a sneak attack from Yoruichi. As he is about to counter her, Yoruichi activates her Shunkō and knocks Aizen to the ground. Yoruichi attempts to follow through with the attack, but is blocked by Aizen. Kisuke then intervenes, binding him with his Shibari Benihime technique and then attacking with Hiasobi Benihime Juzu Tsunagi. After Kisuke's assault seemingly fails, Isshin then attacks Aizen with Getsuga Tenshō.

Aizen emerges from Isshin's attack with a large crack down his new form's face, though he is otherwise unharmed. He states that he understood the attack, and as he raises his Zanpakutō, states that soon they would all understand his power. Soon after, a large explosion erupts behind Ichigo, which Aizen walks out of. Ichigo notices that Aizen has defeated Isshin, Kisuke, and Yoruichi. Aizen asks Gin what he was about to do to Ichigo, with Gin explaining that he was merely testing the boy's power. He then promptly orders Gin to open a Senkaimon, explaining that it would be more convenient to create the Ōken in the Soul Society. Suddenly, the cracked shell on Aizen's face falls apart, with Gin commenting that Aizen's incubation period has ended. With his new form's face exposed, Aizen tells Ichigo that they are leaving him there, and that he would eat him when they are done in the Soul Society. He and Gin then enter the Senkaimon, shutting it behind them.

As Aizen arrives at the Dangai Precipice World world with Gin, he remarks on how nostalgic it is, and asks Gin if he feels the same. He suddenly notices the Koutotsu, which rapidly approaches them from behind. Gin recommends that they move on, reminding him that an entity like the Koutotsu dwells in the realm of reason, not in the realm of Reiatsu, and is thus not something that should be messed with using Reiatsu. Despite Gin's warning, Aizen allows it to collide with him, causing it to explode on impact. Aizen asks Gin what he was afraid of, remarking that reason only exists for those that cannot live without it. As the two reach the Dangai's exit, Aizen declares that they would go on to the edge of reason. Arriving at the Soul Society, Aizen sees that they are not in Karakura Town, and remarks that they were off by a little. Gin tells him not to blame him, explaining that Aizen had caused the axis to slip by destroying the Koutotsu. Aizen admits that this is true, and apologizes for his actions, before inviting Gin to walk the rest of the way. Shortly after, they arrive at Karakura Town. After Aizen remarks that this is inappropriate scenery for Soul Society, he notes that it is likely to be the last time they both see Karakura Town and Soul Society. While in the real Karakura Town, Aizen and Gin encounter a citizen that has woken up confused and turns to them for help. Aizen warns him not to come any closer. The result is that half of the man's spiritual body collapses and fades due to Aizen's spiritual pressure. Aizen states that Humans lack the ability to sense Reiatsu and thus cannot feel his power, but their spiritual bodies are unable to withstand it. Gin then spots Tatsuki Arisawa helping to move her friends and Aizen identifies her as Ichigo's ally from the knowledge of Ulquiorra Cifer's first visit to Karakura Town. As they approach Ichigo's friends, Aizen compliments them on being able to continue existing despite being so close to him. He explains that Ichigo will inevitably arrive there with a new power and states that he wishes to push that power closer to perfection. He says that their deaths will most likely further that goal. When Keigo runs away from them, Aizen tells Gin that there is no need to follow him and that they will start with Tatsuki.

Don Kanonji hits him with a blast of energy, but Aizen emerges from the smoke unscathed and asks the Human who he is. As Kanonji and Tatsuki argue, Kanonji is hit with the overwhelming reiatsu of Aizen. With his Super Spirit Stick in hand, Kanonji charges at Aizen, who causally tells him that if he were to touch him, he would cease to exist. Before Kanonji's attack reaches Aizen, he is stopped by Rangiku Matsumoto, who says that she has made it in time. After Kanonji escapes with Tatsuki and Michiru, Aizen asks Rangiku what she meant and tells her that she is incorrect. Seeing her reaction, Aizen asks if she does not like talking to him. Gin apologizes for her interruption and offers to take her away. Aizen tells him that it is alright as they have ample time. Gin asks if it will be a nuisance, but Aizen claims it will not be. After Gin carries Rangiku away, Aizen says that he is an interesting child, as he has always been. Aizen catches up with the Humans in an alleyway and asks if they expected him to say "I found you" before telling them that he simply stopped pretending to search for them. Mizuiro Kojima throws a bottle at him, but it disintegrates before reaching him. Mizuiro then throws a small gas canister at him and ignites it with a lighter. Unscathed, Aizen follows the group but is attacked by Zennosuke Kurumadani, who uses his Shikai's special ability to trap Aizen under rubble. Aizen, however, easily breaks free. As the Humans run away, Gin returns, prompting Aizen to ask him what happened to Matsumoto to which Gin simply states he killed her. Aizen admits he is surprised as he thought Gin had feelings for her. Gin states he has nothing like feelings. He then reminds Aizen that he told him long ago that he is a snake, and further explains his mannerisms are akin to that of a snake.

He then casually walks by Aizen as the Ichigo's friends run off, prompting Aizen to state that he is tired of playing cat and mouse. Gin then asks what he intends to do with them, to which Aizen states that after killing them he will hang their corpses in a visible location outside of town and then they shall begin creating the Royal Key. Gin tells him it sounds good as he will be the one to kill them all, he then places his hand on Aizen's Zanpakutō blade. Gin then throws up his sleeve and releases Kamishini no Yari from under his arm impaling a surprised Aizen through the chest. Gin looks back at Aizen and states the sole way to escape Kyōka Suigetsu's ability is to be touching the blade itself before "Complete Hypnosis" is activated. He ponders about how many decades it took for him to realize this. He then states that despite not a single being in the Gotei 13 knowing that fact, they all intended to kill Aizen nonetheless. As Gin retracts his Zanpakutō he admits that watching them try kill him put him in suspense, since the only one who can kill Aizen is him. As blood flows out his chest Aizen grabs his wound and tells Gin that he knew all along and he brought him with him to see how he would go about trying to end his life, but he mentions how unfortunate if he that attack would do it. Gin interrupts stating that he never imagined that it would. He then has Aizen take note of a nick in the blade of his Zanpakutō. He then points to Aizen and states he put that little missing piece inside him. Aizen is confused as Gin explains he told him about his Bankai ability a long while back, he then mentions that he lied. Gin admits it doesn't extend as long as he said and doesn't move as fast, either. It simply turns to dust for one moment while extending and contracting. While in the interior of the blades a deadly poison capable of breaking down cells is secreted. Aizen is surprised at the revelation as Gin senses he now understands that during the time between striking his heart and pulling his sword back, he left a tiny sliver of that dust right in his heart. Aizen attempts to say something but Gin simply tells him if he intends to speak he should do so soon, but then again no matter how quickly he tries to talk he is going to die either way. Gin then places his hand up to Aizen's chest and activates his technique Kill, Kamishini no Yari. Aizen curses him as Gin simply smiles and states that Aizen will die with a hole in his chest and asks him isn't that his long cherished ambition. Gin then watches as Aizen chest begins to dissolve from the inside out leaving a gaping hole with the Hōgyoku floating in the middle.

Aizen's body continues to erode from Gin's attack as his assailant watches on. Gin then reaches out to grasp the Hōgyoku in the midst of Aizen's dissolving body, only to have Aizen slap his hand out of the way. Gin manages to retreat nearby, holding the Hōgyoku in his injured hand, while Aizen falls to the ground, after uttering Gin's name. He then screams in rage as energy bursts from his body, erupting into a pillar of light, while Gin watches on in shock. The orb in his hand then disappears, rejoining Aizen's body, which has evolved into an angelic new form. Aizen gives a menacing smile, stating that the victory is his, telling Gin that the Hōgyoku is under his control whether it is in his body or not. He appears quickly behind Gin, and as he turns to face his former captain, Aizen cuts him deeply with one swipe of his sword.

Powers & Abilities
High Intellect: Arguably, the most fearsome trait of Aizen is his tremendous intellect. He is well-versed in the history, strategy, tactics of the Soul Society, and is privy to knowledge previously unknown to many, such as the knowledge of the existence of the ōken, as well as the obscure method in which to make one. He has also created several Hollows and Arrancar while being able to avoid arousing any suspicion from the majority of his fellow Shinigami, most likely due to his Zanpakutō's illusionary abilities. He also, for over 110 years, had been engaging in experiments that involved unique and highly dangerous manipulations of spirit energy and spirit particles. His most startling experiment involves the Hollowfication of Shinigami, something unseen before and still unknown to have ever taken place again. He has an innate knowledge of the Hōgyoku, rivaling that of its creator, Kisuke Urahara, even the extent required for him to destroy it. He is able to figure out Shinji Hirako's Shikai ability's true nature and then deduce that it produces an optical illusion, allowing him to counter its effect. He effectively deduces the true power of the Hōgyoku via trial and error of situations that revolve around it.

Master Manipulator: He has shown himself to be a very crafty and cunning man since his public betrayal of the Soul Society. The most noticeable trait is his ability to deceive and manipulate others around them in multiple manners. For years, he was effectively able to convince everyone around him that he was a kind-hearted man with the best intentions for the Soul Society, while performing horrific actions. He has a great talent for analyzing and observing everything in his presence, allowing him to quickly understand a person's pattern of thinking and better manipulate them. He is also a powerful strategist, capable of formulating well-thought-out plans several steps ahead of others. These plans are incredibly involved and detailed, and are planned-out with the long term in mind, making them seem slightly convoluted. His most well known plan spans over 110 years, a great accomplishment given that it required moving people around like pieces on a chessboard, as well as making sure they played the role he had planned out for them. He is masterful when it comes to "plans within plans," such as kidnapping Orihime, allowing him to use her abilities to extend the shelf life of the Hōgyoku, and to trap the Ryoka and 4 Captains after the departure of Gin, Tōsen and himself in Hueco Mundo, making it easier for him to accomplish the ends of his first plan, to create the ōken and gain access to the Royal Dimension.

Master Tactician: He has also shown himself as a powerful and flexible tactician, capable of adjusting seamlessly to any given combat situation, if not plan out events well in advance. He understands the strengths, weaknesses and mannerisms of his enemies and creates strategies to achieve victory; this includes modifying an Arrancar for the sole purpose of defeating Yamamoto, a Shinigami whose abilities surpass his own. . Though it can be said that the majority of his tactics rely heavily on his Zanpakutō's special ability, there are few better tactics than manipulating all the senses of your opponents, making it easier for one to attack. Despite viewing his power as worlds beyond others, he is also shown to be highly cautious in battle, placing special protections on himself so as to leave no blind-spots.

Kidō Master: Aizen has a great mastery at using Kidō spells. He is skilled enough to use Kidō without the use of their incantation; he used the Black Coffin (ranked 90) spell, and even though he did not control it entirely (utilizing only a third of the spell's original strength), it was sufficient enough to disable fellow Captain Sajin Komamura. He has even used the Splitting Void (ranked 81) spell to block another Kidō attack by Tessai Tsukabishi, who was Captain of the Kidō Corps and reasonably the most proficient Kidō master in the Soul Society at the time, while Aizen himself was only a lieutenant. He can produce powerful protection spells to his person while in battle.

Immense Strength: He is powerful enough to stop Ichigo's Bankai with just one index finger (albeit Ichigo was already battle-worn from fighting Byakuya Kuchiki) and almost cut him in half with a single swing of a sword and stopped Renji's Shikai with his bare hand and broke it with one swing, injuring Renji in the process. He was also able to stop Komamura's Shikai with his bare hand, proving his strength was more than enough to combat someone of his same level. Aizen further shows his strength by being able to effortlessly cut through the sword and wrist of Komamura's Bankai.

Immense Spiritual Power: Even by captain-level standards, Aizen has shown to have tremendous spiritual energy. Marechiyo Ōmaeda commented that Aizen's very presence is monstrously overwhelming. A hint to his actual level of spirit power is given when he turns Wonderweiss Margera into an Arrancar; before activating the Hōgyoku, and states that despite its half-awakened state, it can be fully activated when temporarily fusing with someone with twice as much spiritual power as an average captain-level Shinigami (referring to himself). The force of Aizen's spiritual power is also great enough to, without any visible effort, bring the 6th Espada to his knees. He has commented that it takes a lot for him not to "crush an ant" (referring to Renji) in his path. He also claims that he is more powerful than all of the Espada. Aizen has shown that his reiatsu is powerful enough to nullify abilities, such as when he negated Soifon's Nigeki Kessatsu technique.

Master Swordsmanship Specialist: While the full extent of his prowess has yet to be known, he has demonstrated the ability to effortlessly fight back an opponent's Shikai and Bankai with his own blade still sealed. He has also demonstrated the ability to perform tremendously powerful and precise strikes, capable of cutting through very sturdy targets, such as Renji's Shikai. He was also able to easily cut down four captains (two which used their Bankai) and four Vizard (with three being former captains of Gotei 13) with ease.

Flash Steps Master: He is perceived to be so fast that one cannot discern even being attacked by him until after it has taken place. Aizen is shown to easily outmaneuver Ichigo's Bankai and Hollow mask-enhanced speed to the point he could casually lay a hand on his chest and still dodge a point-blank attack. He is capable of effortlessly dodging simultaneous attacks at close range and the evasion of Bankai level techniques. He moves so fast that opponents commonly do not know his movements until after he has made them and is skilled enough in his movements to evade at high speeds even when being attacked from behind. It's questionable if he is as fast as Yoruichi Shihōin or Soifon, especially seeing as they both caught him before he was able to unsheathe his sword to engage in battle before his escape from the Soul Society.

Master Hand-to-Hand Combatant: While preferring to finish his fights quickly with his Zanpakutō or Kidō, Aizen is a highly capable fighter unarmed as well. Repeatedly, Aizen has shown himself able to effortlessly catch his opponent's weapons barehanded. While fighting offensively, he has shown tremendous agility and dexterity, able to combine both sword and barehanded skills to simultaneously strike with his sword and kick opponents with great force.

Zanpakutō

 * In its sealed form, it resembles a normal katana. The only decoration is the tsuba, which is a hexagon instead of a rectangle. The two sides parallel to the blade are long, whereas the four sides above and below the blade are shortened, making it into almost a diamond or prism-like shape. It has a green handle.


 * Shikai: The release command is and is used to both activate and deactivate it. The name Kyōka Suigetsu hints at its illusionary properties; the moon reflected in water and a flower in a mirror are things that can be seen but not held. It is a Chinese saying for seeing and desiring something that is a dream that cannot be easily grasped in hand, teaching people about temptations.


 * Shikai Special Ability: Kyōka Suigetsu's Shikai ability is . It controls the five senses to the point that it can make the target misinterpret another person's form, shape, mass, feel and smell to be that of the enemy. The initiation condition for the hypnosis is to show the enemy the release of Kyōka Suigetsu. After seeing it just once, that person will completely succumb to the hypnosis. After that, every time it is released, that person will fall under the thrall of the hypnosis. The hypnosis is apparently long-lasting, seeing as the Vizard are still affected by Kyōka Suigetsu even though they were hypnotized at least 110 years ago. Since the spell works when you see the ritual, those who cannot see are consequently immune to the hypnosis. When he turns off the hypnosis by force of will, the image shown melts away/shatters. Kyōka Suigetsu's Complete Hypnosis is absolutely flawless; even if the target is aware that they are under the hypnosis, they cannot resist its influence. Kyōka Suigetsu's hypnotic abilities make it a highly useful tool in combat, as Aizen can quickly create simple or complex illusions to deceive opponents. For example, by creating a decoy of himself, or other illusions to distract his opponents, Aizen can hide his own movements and attack with impunity. His opponent, meanwhile, will remain focused on the illusion until it's too late to react.


 * While the illusions Kyōka Suigetsu creates are quite powerful, those with considerable power and skill themselves may be able to note slight differences in the illusions compared to the real thing, even if they are not able to determine what, precisely, is different. Captain Retsu Unohana was able to detect something was amiss with Aizen's fake corpse, even though she did not realize what until seeing Aizen alive. Kyōka Suigetsu's reiatsu gives it away to those keen enough to sense its actual presence past the illusions created by its complete hypnosis. Gin reveals that the sole way to escape Kyōka Suigetsu's ability is by touching the blade itself before complete hypnosis is activated.


 * Bankai: Not Yet Revealed.

Hōgyoku Implantation
Protective Regeneration: By embedding the Hōgyoku into his chest, it has been demonstrated to actively protect Aizen by healing his injuries almost instantly. Aizen was able to take a point-blank level 96 destruction spell and escape only suffering slight burns. Immediately following that, he took a point-blank mask-enhanced black Getsuga Tenshō and survived the attack. He can come out unfazed after being hurled into several buildings.

Strength Augmentation: Aizen's already considerable strength is further enhanced by the Hogyoku's evolution of his body. He is able to easily strike through a target's flesh with a single nonchalant sweep of his bare hands.

Durability Augmentation: Aizen's durability is further enhanced due to the Hogyoku's evolution of his body. Because of this, he can withstand a level 91 destruction spell without suffering any damage.

Transformation
First Form: After Urahara attempts to block the Reiatsu vents in his wrists with a seal, Aizen emerges from the resulting explosion unscathed as a phantom-like figure. His face is covered with a white canvas and his outfit is now a white cloak that is split in four sections near his waist. There is a cross in the middle of the cloak, showing where the Hōgyoku is embedded in him. After a short struggle with Yoruichi Shihōin, his Zanpakutō becomes fused to his arm. Also, when he is attacked, his body appears to crack and fold under damage, only actually bleeding when an attack is powerful enough. While in this stage, Isshin Kurosaki states that his reiatsu is completely unreadable and that it is likely that only someone in the same place as Aizen would be able to sense it. In this form, he has shown:


 * Enhanced Durability: His durability is great enough to block Isshin's Zanpakutō with his foot and withstand a massive punch from an armored Yoruichi. He has shown to perform as if unharmed, even while taking a lot of damage. He takes on Isshin's point-blank Getsuga Tenshō attack, and seems unfazed by the attack, despite showing a bleeding gash on his forehead.


 * Enhanced Strength: Aizen was strong enough to cause a shockwave after being knocked down by Yoruichi. This shockwave was fast enough and strong enough to catch even Yoruichi off guard and subsequently destroy the Anti-Hierro armor on her left leg.


 * Enhanced Speed: Aizen's newfound power enhances his speed to the point that even captain-level opponents cannot register his movements. His speed is so great that he is able to catch the likes of Yoruichi Shihōin off guard. He can seemingly incapacitate three captain-level opponents instantaneously.


 * Regeneration: Aizen also demonstrates a form of regeneration, as seen when he recovers from Yoruichi's first attack.

Second Form: After completing his "incubation" stage, Aizen shed his sleek phantom-like form to reveal a similar form to his original one, with the addition of long hair, and gray eyes with purple sclera. The exact difference in power between his new form and his previous form is unknown.


 * Immense Durability: Aizen's durability has been further enhanced. He willingly lets the Kōtotsu collide with him, and he remains unharmed.


 * Immense Spiritual Power: Aizen's already enormous spiritual energy is further enhanced, evident by the fact that by just being near a human soul, he causes it to collapse and fade away. By his own claim, if Don Kanonji had come into contact with Aizen, the former would cease to exist. Just touching the arm of Gin Ichimaru caused the area touched to dissolve.

Third Form: After having a hole opened up in his chest by Gin's Kamishini no Yari, spiritual energy erupts from his chest and Aizen emerges from the blast in this new form. In this form, he has a hole in the center of his chest with a cross in the middle of it. The form-fitting white robe that enveloped him in his past two forms lengthens and flares out at the ends. In this form, his irises vanish, as well as his eyebrows and the hair curl that usually hangs over his face. There appears to be diamond shape embedded in his forehead. He has also gained three sets of butterfly-like wings.

Appearances in Other Media
Aizen is an unlockable character in the Bleach video games. Being the central antagonist, most games have him as the final boss, such as in Bleach: Soul Carnival. His Black Coffin Kidō spell is one of his best attacks. He also makes use of his Zanpakutō's illusionist abilities throughout most of the games. He makes no appearance or reference in the films; though, in the second OVA, he is seen drinking coffee at the very end with Gin and Tōsen. He also has his own Bleach Beat Collection, Hanabira and Kyōka Suigetsu.

Reception
IGN.com praises the animators for how Aizen was revealed as the primary antagonist saying that "The Aizen that we first knew was the nicest guy ever, he looked it, and now this Aizen actually looks like the most evil jerk we've ever seen. It's just great how the animators haven't changed his animation much, but have managed to give his face this evil thing about it." However, they were critical of Aizen's convoluted plan, calling it "...so planned out was a bit too planned out to believe. He seemed to know that everything was going to happen exactly as planned...." Concerning his Zanpakutō, IGN described it as overpowered, calling it "the most unbalanced sword in Bleach." The site found it "far-fetched for some reason to think that nobody can tell when they're getting hypnotized, even the higher ups."

Trivia

 * Aizen's Kyōka Suigetsu came 18th in the Zanpakutō popularity poll. He himself came 23rd in the 4th, the latest, character popularity poll.

Quotes

 * (To Tōshirō Hitsugaya)"You should learn this well, Hitsugaya-kun. Admiration is the emotion furthest from understanding."


 * (To Renji Abarai)"The Sōsuke Aizen you knew...never existed to begin with."


 * (To Jūshirō Ukitake) "No one stands on the top of the world. Not you, not me, not even gods. But the unbearable vacancy of the throne in the sky is over. From now on...I will be sitting on it."


 * "The betrayal you can see is trivial. What is truly fearsome, is the betrayal that you don't see, Captain Hirako."


 * (To Tia Harribel indirectly) "I never would've imagined that the power of the Espada I so painstakingly assembled would be less than mine alone"


 * (To Shinji Hirako) "Trusting in someone is the same as depending on them. That is something the weak do. We have no use for it."


 * (To Shinji Hirako) "All living creatures place their faith in someone more powerful than them and they cannot survive unless they blindly follow that person. The recipient of that faith then seeks out someone in an even higher position in order to escape from the pressure. That person than seeks out someone even more powerful that he must put his faith in. In this way all kings are born and in this way all Gods are born. Do not believe in me yet, Hirako Shinji for now I shall slowly teach you who the God is that you will put your faith in. Believing in me comes after that."


 * (To Ichigo Kurosaki) "Why are you putting so much distance between us? If you want to make sure it hits me, then you should get close and fire. Or is it that you're afraid of letting even a part of me out of your field of vision by getting close? If that's the case, then it's a foolish thought. Distance only has meaning in a fight between equals. With you and I, distance holds no meaning at all. Watch... If I do this, my hand is almost instantly at your heart."


 * (To Sajin Komamura) "You thought you could destroy me by striking with power? How naïve. ...no perhaps we differ in our basic understandings of the word "power". I shall enlighten you. This is what is known as "power"."


 * "I will not take your lives. With the measure of power that you possess you are unlikely even to lose consciousness from those wounds. Stay there, helpless and defeated and observe carefully as this battle reaches its conclusion."


 * (To Genryūsai Shigekuni Yamamoto) "Your Ryūjin Jakka is indeed the most powerful Zanpakutō in existence. There is no doubt about that. Were I to fight against it directly, it would likely overpower even me. However, if one abandons all other abilities and focuses his strength entirely on a single specialized skill, then he can overcome even the greatest of powers."


 * (To Genryūsai Shigekuni Yamamoto) "Cruel? A soul that's become a Hollow has no purpose. It does nothing more than meaninglessly hunt down souls to prey on. What is so cruel about granting meaning to such an existence? I would say that you're the one who's cruel for smashing that soul to pieces."


 * (To Genryūsai Shigekuni Yamamoto) "To you, I will not say "I will not kill you". You who are the very history of Soul Society itself and as such, you alone will die by my sword."


 * (To Ichigo Kurosaki) "I suppose it is only to be expected. You have my pity. There is no such thing as 'truth' or 'lies' in this world; there never has been. There is only plain, hard facts. And yet, all beings who exist in this world take only those 'facts' that are convenient to them, and take them to be the 'truth'. They do so because they know no other way to live. However, for those powerless beings that make up the majority of this world it is those 'facts' that are inconvenient for their own self-affirmation that make up the real 'truth'."


 * (To Isshin Kurosaki) "...But living creatures are strange. They are made in such a way that they can actualize only what their minuscule minds wish for."


 * (To Kisuke Urahara) "Allow me to be careless, as I don't have the need not to be. I can feel the strength of the Hōgyoku in my body. My strength exceeds my older self. I'm now invincible so I don't have the need to dodge a level 90 Kidō anymore."


 * (To Gin Ichimaru) "Reason exists for those who cannot go on living without clinging to it. Now let's go... to the edge of reason."

Navigation
Sōsuke Aizen Sōsuke Aizen