Reiatsu, or Spiritual Pressure, serves as the foundational basis of most of the techniques practiced by the Shinigami, Quincy, and Arrancar in Bleach. In contrast to Reiryoku, which translates as Spiritual Power, Reiatsu is the actual force exerted by an individual's Reiryoku when it is released. Those with high levels of Reiryoku generally tend to have more intense Reiatsu and by extension, scale higher in the hierarchy of power among the main cast of Bleach.

Individuals can hone and develop their Reiatsu through training, which increases their reserves and improves their control. Essentially, Shinigami battles are a contest of Reiatsu, with strategy only serving to turn the tide in critical moments. Additionally, the Gotei 13, Soul Society's military branch, has its own method of classifying an individual's Reiatsu on a scale that ranges from 1 to 20. Lieutenants in the organization generally fall into the ranks of 4 or 5, whereas Captain-level Shinigami generally rank in the 3, 2, or 1 brackets. Quite a few characters in the series possess exceptionally potent Reiatsu, but who among them had the most powerful Spiritual Pressure in the series?

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10 Kenpachi Zaraki

While some might argue that he should be higher on this list, Zaraki does lack some degree of control over his Reiatsu, as he did not receive training like most Shinigami. In fact, when released, Zaraki's golden yellow Reiatsu can cause immense shock and confusion while destroying the surrounding area. In combat, it can act like armor and prevent weaker opponents from wounding him.

For the most part, Zaraki has to use a Reiatsu draining eyepatch to keep it at a level that he can manage. There is no doubt that he possesses the best growth rate and potential for any Captain in the Gotei 13, but ranking higher would necessitate him gaining more control over his powers.

9 Jushiro Ukitake

The Captain of the 13th Division, who also hosted the right arm of the Soul King Mimihagi for most of his life, Jushiro Ukitake possessed very high reserves of Reiatsu. However, due to the debilitating illness, he suffered from since birth, he required a considerable deal of energy just to remain alive and functional. Despite this, he is easily one of the most powerful Gotei 13 Captains in history, having been trained by Yamamoto himself, with Reiatsu that only his comrade and close friend Shunsui Kyoraku, can equal among the Gotei 13.

8 Shunsui Kyoraku

Another one of Yamomoto's former students, Shunsui Kyoraku, also possesses Reiatsu, which is far beyond the limits of any other Captain in the Gotei 13. The fact that he was easily able to stand in Yamamoto's presence when the Captain-Commander unleashed his Reiatsu and remain unfazed is a testament to his own reserves, as most would be overwhelmed by Ryujin Jakka's power.

Furthermore, he was able to take on and defeat the 1st Espada, Coyote Starrk, with only his Shikai, indicating that his full power is something even more fearsome than what Aizen's subordinates could muster at their best.

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7 Gerard Valkyrie

The heart of the Soul King and one of the most powerful among Yhwach's Sternritter, Gerard Valkyrie possesses immeasurable reserves of spiritual power, in no small part due to the unique powers he wields. For starters, "The Miracle" permits him to expand his speed, power, and size infinitely against overwhelming odds, to a degree where his Reiatsu was so potent that he could no longer sense the other Gotei 13 Captains. Even Kenpachi Zaraki was forced to remove his eyepatch before facing him, which highlights his incredible Reiatsu reserves.

6 Genryusai Shigekuni Yamamoto

The Captain-Commander of the Gotei 13 and one of the longest-serving Shinigami in history, Yamamoto possesses near immeasurable reserves of potent red Reiatsu, which can incapacitate all around him when unleashed. That being said, he can also control it masterfully, having honed his skills for centuries.

There has been no Shinigami stronger than him since the inception of the Gotei 13, and he was considered irreplaceable even in old age. Both Aizen and Yhwach avoided fighting him one on one as they were not confident in their ability to defeat him, attesting to his overwhelming strength.

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5 Ichibe Hyosube

Ichibe Hyosube is the Leader of Squad 0, also known as the Royal Guard, and another one of the longest-serving Shinigami in history, perhaps even longer than Yamamoto himself. Over the millennia, he has refined his skills; he has reached a level of Reiatsu control that virtually no other Shinigami in history could even fathom. Able to fight on even terms with Yhwach using only his Shikai, Ichibe is in a class of his own and was counted among Soul Society's 5 Special War Powers by the Wandenreich, with the full extent of his power still yet to be depicted.

4 Sosuke Aizen

Boasting colossal Reiatsu that is colored violet, Sosuke Aizen was chosen as one of the 5 Special War Powers by the Wandenreich purely based on this quality. Even for a Captain-level Shinigami, Aizen had a level of Reiatsu that was truly fearsome, which increased exponentially once he fused with the Hogyoku. His sheer presence could incapacitate weaker opponents even prior to his evolution.

Despite his defeat and imprisonment in the Muken, Aizen managed to surpass even his Hogyoku forms, with his Reiatsu becoming so monstrous that he had to be restrained in a chair that suppressed it. He was able to effortlessly vanquish multiple Captain-level Shinigami without taking damage and can even condense his Reiatsu into a shield to protect against attacks.

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3 Ichigo Kurosaki

Ichigo's mixed heritage, coupled with his ridiculous growth rate, was the reason behind his classification as one of the 5 Special War Powers, with the Wandenreich choosing to invade Soul Society only after he was imprisoned. He was able to match a Hogyoku-enhanced Aizen after training in the Dangai, attaining a level of power that even he could not comprehend.

Additionally, Ichigo also went toe-to-toe with Yhwach, the father of all Quincy and a divine being. Plot armor or not, he is Bleach's protagonist, and as such, he is easily one of the most powerful characters in the series with monstrous reserves of Reiatsu.

2 Yhwach

The son of the Soul King and father of all Quincy, Yhwach is a divine being with almost infinite reserves of Reiatsu, possessing the power to obliterate virtually any opponent that stands before him. He also possesses the unique ability to extract and redistribute power from the Quincy to himself and vice versa, making his strength all the more intimidating.

Yhwach also possesses an especially powerful ability known as The Almighty, with which he can see into the far future and rewrite things as he wishes. In his first confrontation with Ichigo, Yhwach easily overpowered him and remained unfazed even when fighting against his Bankai.

1 Soul King

A godlike entity who is responsible for protecting the balance of souls coming in and out of Soul Society, the Soul King is an omniscient being who has been restrained for the purpose of maintaining this balance. His right arm, left arm, and heart were all severed from him at one point, having gone on to become powerful entities themselves.

Considering the sheer extent of his responsibilities and the power he wields to maintain the balance between realms, it is no surprise that the Soul King is the being who possesses the most Reiatsu in Bleach, with the true depth of his power escaping the limits of human comprehension.

BLEACH: Thousand-Year Blood War Part 2 – The Separation is available to stream on Hulu and Disney+.

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