Onmitsukidō

"If you see your allies losing, that's your chance. Don't step between them. Take the enemy down from behind. And if the enemy is so strong you can't even do that, then just watch your ally be killed. That's what it means to be Onmitsukidō." - Soifon

The, also called the Secret Mobile Unit/Corps, Special Forces or Covert Ops, is the second largest organization that Shinigami join, and one of the three main branches of military in Soul Society.

Overview
The Onmitsukidō is one of the three forces under the direct supervision of the Central 46 Chambers. If the Gotei 13 operate openly, the Onmitsukidō patrols and conducts surveillance in enemy territory and carries out top-secret operations, such as assassinations and the execution of Shinigami who have broken the law. If the Gotei 13 are considered an exterior guard, then the Onmitsukidō is an interior, covert guard.

Originally a separate branch of Soul Society's army, the Onmitsukidō was traditionally tied to the Shihōin family. When the Commander-in-Chief would gain a title within the Gotei 13, the Onmitsukidō would become attached to that division as well. The Special Forces is generally commanded by a member of the noble family Shihōin, though the last member to hold this position was Yoruichi Shihōin before she departed Soul Society around 100 years before the main story line. Since that time, the Special Forces seem to be highly merged with the Gotei 13's 2nd Division.

Onmitsukidō Ranks
The head of the Onmitsukidō is called. The leaders of each of the divisions are ranked as. Given that the Onmitsukidō is currently tied with the Gotei 13's 2nd Division, each Corps Commander also holds a Seated Officer position in said division. The Commander-in-chief of the Special Forces generally also commands top division of the Special Forces, which is the Executive Militia and it is known that the 3rd Seated Officer is the Corps Commander of the Detention Unit. It may be said that the order of the five divisions also goes in order of the top five officers of the 2nd Division. (Unlike the Gotei 13 Captains, the Commander-in-chief has several bodyguards, though its current Commander-in-chief Soifon has never been seen with any).

Current

 * Soifon - Soifon inherited both the title of Commander-in-chief of the Onmitsukidō and that of the Captain of the 2nd Division after the departure of Yoruichi.

Former

 * Yoruichi Shihōin - As the 22nd head of the Shihōin family, one of the four noble families, she was the first female to hold that position as well as being the first female to be the head of the Onmitsukidō. Because she was Commander-in-Chief of the Onmitsukidō prior to gaining the position of Captain of the 2nd Division, she was also the one responsible for having brought together the 2nd Division and the Onmitsukidō.

Special Forces Divisions
There are five divisions within the Onmitsukidō, for which the first has the most authority, and the fifth has the least. The five divisions in order of authority are:

1. Executive Militia

 * The first branch of the Onmitsukidō. It is ranked the highest of the five branches in the division. The Executive Militia carries out missions that involve combat. They specialize in the unarmed combat technique known as Hakuda and is able to operate silently and in secrecy. Their responsibilities including punishment and assassination of ex-comrades who break the law and acting as scouts during battle against Hollows. Its members are dressed all in black and are known for their cold-bloodedness. It is normally headed by the the Commander-in-chief of the Onmitsukidō.

Current
Corps Commander
 * Soifon - Soifon is the current Corps Commander for the Executive Militia.

Former

 * Yoruichi Shihōin - Yoruichi was the Corps Commander for the Executive Militia 100 years prior to the main story line.

2. Patrol Corps

 * The second branch of the Onmitsukidō. The Patrol Corps is assigned mainly to the Seireitei area and gathers data on uprisings. In the event of those under house arrest escaping they also are tasked with finding and apprehending them. Externally they patrol the various lands and dimensions to combat dangerous Hollows and other enemies of Soul Society.

Current
Corps Commander
 * Marechiyo Ōmaeda - Marechiyo is the current Corps Commander of the Patrol Corps in the Onmitsukidō. He is also the lieutenant of the 2nd Division under Soifon.

Unit members
 * Eikichirō Saidō - Eikichirō is a Shinigami who was sent to investigate Rukia Kuchiki when she disappeared in the Human World. (anime only)

Former
Unit members
 * Shūsuke Amagai - It was stated that prior to his promotion to Captain of the 3rd Division Amagai served in the Patrol Corps; however, it was not stated whether he was part of the 2nd Division. (anime only)
 * Makoto Kibune - Makoto served on the same patrol unit as Amagai before becoming the 3rd Seat of the 3rd Division. (anime only)

3. Detention Unit
Detention Unit: The third branch of the Onmitsukidō. The Detention Unit is responsible for the imprisonment and supervision of all criminals within the Seireitei. They also have another duty known as Special Detention, which concerns those who joined the Gotei 13 but were judged to be a danger to their fellow Shinigami. They investigate, apprehend, and keep these individuals sealed away from the rest of Soul Society within the Special Underground Detention Facility, aka. the Nest of Maggots. It should be noted that those few who are kept in the Maggots' Nest have not actually committed any crime but have been identified by the laws of Soul Society as "Dangerous Elements". This unit acts somewhat similar to a prison and mental rehabilitation center. The activities of this division are shrouded in mystery and remains virtually unknown to the majority of the public as well as most Gotei 13 members up to the level of Lieutenant.

Former
Corps Commander
 * Kisuke Urahara - Urahara was in charge of maintaining the Nest of Maggots until his promotion to the rank of captain of the Twelfth Division.

4. Un-named
The fourth unit's name and function are unknown. The activities of this division are shrouded in mystery and remains virtually unknown to the majority of the public as well as most Gotei 13 members up to the level of Lieutenant.

5. Reversal Counter Force

 * The fifth branch of the Onmitsukidō. The Reversal Counter Force serves as the communication link for division members. A special ops unit that is mobilized whenever a mission is urgent and requires secrecy. Many of its members are masters of Shunpo.

General Attire
Although the general Onmitsukidō uniform appears to be the standard Shinigami uniform, the Executive Militia uniform is different from the Gotei 13. Overall, it resembles a ninja uniform. It has no visible white undergarments and the sash is dark as opposed to white. A headpiece covers the bottom part of the face and sometimes the top, but not the eyes; they wear no sandals, but long jika-tabi, and tight bands are on the legs and arms to keep the clothes from moving too much, which both are presumably for silence of movement. Members of the Executive Militia also wear their head covering on the top, not just the bottom and wear a black sash instead of a white one.

Executive Attire
Battle dress approved solely for the Corps Commander of the Executive Militia. Its backless and sleeveless design is unique. This is to prevent the fabric from being ripped away by the high-density kidō produced by the fighting style, an advanced technique that combines hand to hand combat and kidō, causing high spiritual pressure to accumulate at the shoulders and back, blasting away the fabric at said places.

Correctional Attire
The Correctional Force uniform is radically different. The soldiers wear a white uniform, a long piece of headgear, and a backpack.