Onmitsukidō Information

The Onmitsukidō, 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.

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 Onmitsukidō is generally commanded by a member of the noble family Shihōin, yet the current captain, being Mukuro, it is now commanded by a member of the noble family Sazumushi.

Mission
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.

Structure
The Onmitsukidō is made up of five components: They are split into five divisions all excelling in specific specializations.
The Onmitsukidō is led by a Commander-in-Chief (総司令官, sōshireikan), who has the statuary authority to conduct all the affairs of the Onmitsukidō; while deferring to the authority of the Central 46 Chambers in matters involving Soul Society and the Captain-Commander in all military matters.

The leaders of each of the divisions are ranked as Corps Commander (軍団長, gundanchō). 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 Onmitsukidō generally also commands top division of the Onmitsukidō, which is the Executive Militia and it is known that the lieutenant is the Corps Commander of the Patrol Corps and 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.

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:

Executive Militia
Commander - Mukuro Sazumushi
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.

Spoiler:

Patrol Corps
Commander - Currently Unknown
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.

Spoiler:

Detention Unit
Commander - Mukuro Sazumushi
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.

Spoiler:

Reversal Counter
Commander - Unknown
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.

Spoiler:

The 5th Division is currently unknown

Onmitsukidō Uniforms
Executive Militia Uniform
Overall, Executive Militia uniform 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.

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 Shunkō (瞬閧, flash cry), 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.

Reversal Counter Force Attire
The Reversal Counter Force Shinigami wear a maroon kimono over the black form-fitting legging and long sleeved tops. They also wear hats and a carry a backpack.

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

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