You wouldn't know by looking at it, but Sekirei have some pretty impressive feats when compared to other anime and battle manga.
That being said, it has been stated multiple times that MBI made adjustments to all sekirei which limited their abilities, which I will cover later.
Lets start with the original five plus an honorable mention. Miya Asama, Matsu, Kazehana, Karasuba, Mutsu and Yume.
Sekirei number 8 Aka the Sekirei of fate Yume. Also the discipline squad's second generation leader.
The first Sekirei I will be covering is the Original discipline squads leader Miya Asama.
If you see these eyes, you`re probably already dead.
Miya is a being that is classified as a being that is neither Sekirei nor human. She is in fact two different people.
the first being No. 1 and the very first sekirei of this generation, and she is also the original goddess of all sekirei who is known as no. 0
Miya is an unwinged Sekirei, as her husband, Takehito Asama, was not an Ashikabi. She is Sekirei #01 and the feared leader of the 'First generation', former Disciplinary Squad, although Miya claimed that she was a completely different person in the past during the time when she served MBI. The one responsible for changing Miya was Takehito, who later on became her husband. She stated that it was thanks to him that she was able to learn about the people and the world which changed her view on life. Though, after some time, Miya came to suffer as Takehito died indirectly thanks to her actions which resulted in Miya leaving MBI and maintaining the Inn that her husband built, where she would never refuse anyone who needed shelter.
In Izumo Inn, Miya is often described as a mother figure to the others, which is strongly denied by Miya, who states that everyone views her more as a big sister. She looks after everyone, trains Minato's Sekirei and was willing to go and kill Minaka if Homura would have simply asked her to. Though she cares about Minato, Miya often enjoys to make fun of him in a slightly sly and teasing manner, throwing several embarrassing remarks in the presence of his own Sekirei and stated that it has become quite lively ever since he arrived. She also has a tendency to listen secretly to other people's conversations (mostly Minato's) by passively wiretapping using a rubber duck with a speaker, which was made by Matsu.
Despite being the caring/maternal figure in Izumo Inn, there are also rules set up by Miya in which she prohibits fighting, obscenity, and illicit sexual activity in her house. When she becomes angry, annoyed, or if any person breaks the rules of the house, and when she is giving threats (such as if Minato and the others learn too much about her past she'll kick them out and leave them in the streets) a demonic visage appears behind her and is frightening enough to scare even Homura and Tsukiumi into submission. It is possible that she learned it from Takehito Asama doing it first, an act which made her smile for the first time. This small habit, coupled with her strength, is what causes others to fear her as the "Hannya of the North".
Miya has shown to be on very bad terms with Sekirei #04 Karasuba as she threatened that she wouldn't allow her to get away if she would come near Izumo Inn ever again.
She is very fond of all of Minato's sekirei, and has even said that she thinks that they are too good for him, despite Matsu's objections. Miya has even fought together with two of Minato's Sekirei, Matsu and Kazehana, when they were all in the disciplinary squad together.
She is also sync with the Sekirei spaceship Kouten and she is able to move it around in space while on earth at anytime.
Power-wise Miya is the most powerful Sekirei in existence and the only Sekirei without an Ashikabi.
Her speed is greater than her sisters being hypersonic to hypersonic+. this mean that she is high Hypersonic + to massively hypersonic.
Miya speed blitzed Karasuba and cut her down, leaving her for dead. this is all covered in Chapter 140 of the sekirei manga.
Miya and the other four Sekirei have fought in wars against tanks, submarines, machine gun, helicopters etc.
They are out running bullets from machine guns, tanks, missiles and thinks faster than supersonic speeds.
Miya's Destructive capability is pretty good as well, as her greatest feat shown is the ability to sink large battleships casually.
Miya's DC is City level as she can reduce a city to rubble (She is not on vaporizing level). Miya's durability is city level as well.
Miya's reaction time is at the least hypersonic + as she was able to react and blitz pass Karasuba who while unarmed was aiming to kill and moving at hypersonic + speeds.
Miya's striking speeds is High hypersonic+ as she was able to cut Karasuba down faster than she can react. Miya is also able to create shockwaves strong enough to sink battleships with a single casual swing.
Miya has killed hundreds of people during her time as the leader of the DS.
Next is Sekirei Number two Matsu and Minato's second sekirei.
Matsu is Minato's third winged Sekirei and serves as his personal source of information (she often refers to herself as the 'Wisdom' Sekirei). However, despite her high intellect, she is very perverse - she uses her resources to peep on people and often tries to "experiment" (implied to be sexual acts) with Minato and so most call her the 'Shameless' Sekirei. This perversion even extends to her interactions with Homura, who would usually retaliate by comically charring Matsu with pyrokinetic flames, and leaving the latter with torched and curly hair (in the anime, her hair becomes an afro after being burned). She has also expressed some sexual interest in Musubi when she accidentally kissed her. One of her more harmless hobbies is watching the mayhem that Minato and his Sekirei cause every day, which started when she was originally stalking Minato. Matsu also often shows her dislike for Minato's lack of confidence, noting that she wants him to believe in his own possibilities and stated in a private conversation with Miya, that Minato, would be the one to change their fates.
Matsu is the only member of the discipline squad that doesn't have any physical combat abilities. Instead she has the ability to access and analyze electronic devices on a telepathic level. however that being said, she isn't powerful enough to take control of them just yet, with the exception of a single satellite in space that has a particle beam she can use as her made attack.
Matsu mostly uses her ability to identify several enemy forces and assist the Discipline Squad during battle by telepathically communicate information to the other discipline squad members. Other than these abilities Matsu is the only severely limited of the first generation during the war.
Matsu doesn't have many feats outside of being a genius hacker that can crack almost any computer security system outside of MBI. That being said, Matsu has single-handedly killed dozens of people.
The Next Member of the original squad is Minato's fifth sekirei Kazehana the wind sekirei.
Normally, Kazehana displays a very relaxed personality and often becomes giddy when discussing matters of love. She's also confident in her natural sex appeal and not afraid to speak her mind as she openly admitted in front of the others that she loved MBI Director Minaka Hiroto, however she was rejected after the confession as he loved someone else.
Power-wise Matsu has stated once that even no.5 Mutsu of the original discipline squad is no match for her.
She is at least hypersonic + with the possibility of being faster. she has been shown to be faster than Tsukiumi, but she has speed blitzed and outclassed Haihane who's ability mostly revolves around her claws and speed.
Kazehana's reaction time is hypersonic + as well, as she has reacted to helicopter fire, and many other things during the war.
Kazehana has fought Uzume, Haihane, Tsukiumi, Benitsubasa, Kaie and Shi and in all of these fight, she has been proven to be too strong and fast.
Kazehana DC: City block level + to multi city block level due to the fact that her powers work best in large areas. Kazehana Durability is city block level. additional ability is using her wind powers to fly.
Now it's finally time to start talking about a Norito which is basically awaking a sekirei's powers.
Norito: Releases a massive burst of wind combined with flower petals, capable of massive damage in a specified direction.
: Winds of my pact, blow away my Ashikabi's dark clouds!
English Anime Prayer: By the Four Winds of the contract, My Ashikabi's dark clouds will be blown away
Special move: Flower whirlwind
Kazehana control over the wind increases once she uses her Norito. DC: Multi City block + Durability multi city block level. Speed is Hypersonic + to just below massively hypersonic. reaction time is still hypersonic + and her striking speed is also still hypersonic +
The Next sekirei we will be covering is no. 4 Karasuba Aka the black Sekirei
Karasuba is arguably the most dangerous entity in the series and has killed more humans and even other sekirei in the series than anyone else. Karasuba is the fourth Sekirei within the first generation and is also the only one of the 1st generation discipline squad that chose to stay and has been a member in all three generations. In the second generation there where only two members, Karasuba and sekirei number 8 Yume.
Karasuba is the third strongest in the series and is the most blood thirsty. Karasuba is the one sekirei that is shown actually killing people up close and she is also the one that isn't hesitant to actually kill other sekirei, as most sekirei tend to only injure each other to the point were the body reaches it's limit and shuts down.
when this happens it has been stated that the Sekirei in question is still alive, however when Karasuba kill a sekirei, she actually goes for the kill without any hesitation.
Karasuba: Hypersonic + able to outrun, bullets, tank fire, machine gun fire, anti aircraft rounds, etc. DC: City maybe higher. Karasuba has killed an entire army with tanks, and helicopters all singlehandedly and an Army with jets, helicopters, Submarines, tanks, etc with Miya, Kazehana, Matsu, Mutsu, and Yume.
Norito: This is the pledge of my blade, exterminate the sworn enemy of my Ashikabi! Karasuba gets an extreme boost in power and she unleashes her most powerful move.
Special move: Long blade of the underworld: Eternal Rage: The user swings their katana, which, when crossed with the blade of another, creates an explosion of highly pressurized air.
As a testament to her strength and durability, Karasuba has tanked her own Norito as well as another sekirei's when it's power was redirected back at her during her fight with Kaho.
Karasuba has tanked the power of her own attack as well as the Norito attack from Kaho at the same time and Kaho was not only faster than Karasuba was, but easily stronger.
during their fight, Kaho was dominating the fight and Karasuba could hardly keep up until Kaho cut her down, then Karasuba appeared behind her in an instant, faster than Kaho could track and pierced the girls heart. Female Kenpachi anyone.
As a side note, when this happened she was in a bloodthirsty state of mind and She was even prepared to kill her own Ashikabi just because he had asked a very inappropriate (at the time) question.
This makes Karasuba the most dangerous sekirei within the series. There seems to be no love between her and her Ashikabi Natsuo.
Now it is time to introduce the final member of the first generation. this is sekirei number 5 Mutsu
Not much is known about mutsu actual skill, however it has been shown and stated that out of all of the members excluding Matsu, that he is the weakest. That being said he is still stronger than most of the double digit sekirei and the triple digit sekirei.
Mutsu's sekirei abilities are earth base and reliant on his sword. He is a master swordsman like both Miya and Karasuba and his most destructive ability is the ability to cause earthquakes, tearing apart the ground by hitting the end of his scabbard on the ground.
Like the others Mutsu's speed and reaction time is Hypersonic as he is able to dodge tank fire machine gun fire etc. DC: City block +, Durability is City block +. striking speed is about hypersonic.
Move: Hasaiten (破砕点, Smashing point). he uses this move to cause small earthquakes.
Norito: has yet to be seen. (Update later)
He was once a member of the first generation Disciplinary Squad and participated in defending Kamikura Island, but for unknown reasons he left the Squad and vanished. Some time later he got "called" by Mikogami, reacted over distance to him, and came to the capital in search for his Ashikabi. He found Mikogami during a fight with thugs who tried to extort him. Even so he didn't want to fight in MBI's territory he defended Mikogami and became his Sekirei.
He is a composed and calm Sekirei who has been shown to be capable to judging situations carefully and act immediately based on his judgment, as seen when he instantly retreats against the will of his Ashikabi from the Homura hunt when the East appears or when Yukari wings Shiina. Miya described him as someone that was hard to keep a hold of and expressed her surprise that he has become the South's Sekirei.
And now that we have all the original squad out of the way it is time to talk about the sekirei who sacraficed herself so that the first main girl Musubi could live on and find Minato. The self-proclaimed Sekirei of fate and the most legendary being in the series. Sekirei number 8 Yume.
Yume: Birds that love. The rumored name of the Sekirei. People are said to become stronger by loving and being loved. Once again the same as Sekirei. They are little birds who will one day spread their wings and show love to the world. Therefore, I, who can't fit into this natural order, will at least protect those baby birds.
That's what it means to be the Fate Sekirei.
Yume is a sekirei who bares a striking resemblance to the Main(main) heroine Sekirei Musubi to the point where if they were standing next to each other, you would mistake them for twins. In fact personality wise they are the same with the only exception being that Yume was more mature and Musubi has a bigger bust.
Before the beginning of the main series, Yume was the leader of the second generation discipline squad alongside Karasuba. (they were the only members)
Yume was a firm believer that Sekirei exist to find their Ashikabi and fall in love. She referred to herself as the defender of love and her name Yume means Dream, in reference to her dream of freeing all of her sisters and brothers into the world so that they could find their Ashikabi.
Yume's sekirei crest is the most unique in the series as it is located on her chest.
Before the series had begun, Yume rescued Musubi, when she was a child, and saved Musubi's life by giving her "Tama" (the core which let Sekirei live and use their powers) to Musubi. Later it was revealed that along with Musubi, Yume saved Kaho who was also kidnapped in the same incident.
When Musubi lost her Sekirei crest fighting Benitsubasa, Yume's soul temporarily took control of her body, defeated the Disciplinary Squad and was able to restore Musubi's crest. In the anime she asked Minato to teach love to these little birds (a reference to Sekirei). She said that she was awakened by Minato's warm and gentle spirit.
In terms of strength speed and power Yume is in a whole other dimension then all of the other sekirei. The first time she had taken control of Musubi's body, she beat both Benitsubasa and Haihane with ease and then threw them both miles away with one hand each.
Yume arguably the strongest character in the series, she may even be stronger than Miya.
Yume speed and reaction time is Massively hypersonic+ as not only did she dodge all of Karasuba's sword swings, but she has been shown to be able to keep up with Miya casually. Not only than, Yume has also been shown to casually dodge machine gun fire without even trying.
Yume's sekirei ability is her combat prowess and her ability to fire light base energy blast from her hand.
A punch from Yume is the equivalent to a Nuke.
Because of the fact that she was holding back Yume DC is not calculated however If we base all of her strength Musubi's and on the fact that she can match Miya casually she would be around here.
DC: City , Durability is City . however this could likely be greater.
And there you have it. I have covered all of the first and second generation Discipline squad members the Next one I shall be going over is the Single numbers that came after the discipline squad.