Misaka Mikoto/Chronology (Toaru Kagaku no Railgun)

Toaru Kagaku no Railgun
Mikoto, Uiharu Kazari, Saten Ruiko, and Shirai Kuroko were going to a game center, but along the way, the girls get sidetracked to a crepe stand so that Mikoto can collect the figure being given away. The situation suddenly turns bad when a nearby bank gets robbed. In response, Kuroko and Uiharu go to the scene as members of Judgement, and Kuroko asks Mikoto not to get involved. While Kuroko is fighting the robbers, one of them manages to get away from her and tries to kidnap a little boy. Saten manages to grab the boy, but one the robbers kicks her. Seeing this angers Mikoto, deciding to use her railgun ability on the robbers' car, throwing it into the air and wrecking it. When Anti-Skill shows up to arrest the man, Saten gets thanked by the boys mother, and even Mikoto compliments her.



In a flashback, one night Mikoto is shown being hit on by delinquents, when a certain boy named Kamijou Touma tries to save her from them - even though she doesn't need any help. After unintentionally insulting Mikoto while trying to convince the delinquents to stop bothering her, she discharges a powerful electrical attack on them out of rage. Believing that she has defeated them all, she goes to leave, but to her surprise she sees Touma is unharmed. Because of this initial encounter, Mikoto constantly tries to make the reluctant Touma fight her whenever they meet. This is due to him being the first person to not only walk away from her attack unscathed, but to also negate it completely.

Level Upper Arc
Uiharu gets a cold and cannot go to school, so Ruiko, Mikoto and Kuroko pay her a visit. Kuroko becomes curious as to how Hatsuya, a Level 2 esper, had powers equivalent to a Level 4's. Mikoto brings up the Level Upper urban legend Ruiko had mentioned, and Kuroko points out this is not the first time a user's power and the user's level have been vastly different. After discovering where they can get information on the Level Upper, Mikoto goes to a restaurant and pretends to be an interested customer to a group of teenagers who may have information about Level Upper. Mikoto eventually gives up the act when they won't tell her what she wants and soon faces their leader, a girl with the ability to manipulate asphalt. Mikoto wins the fight, but damages a nearby generator causing a city-wide blackout. The next day, Kuroko and Mikoto discover that Hatsuya, along with several others who have shown abnormally strong powers, have all fallen into comas. Meanwhile, Ruiko discovers the Level Upper on the internet by chance.

Mikoto and Kuroko talk with Harumi Kiyama, the AIM specialist Mikoto had previously met, about the Level Upper. They are later joined by Kazari and Ruiko, the latter of which has the Level Upper, but decides to keep it to herself when Kuroko mentions its related to criminal activities. Mikoto later catches up with Ruiko, noticing she's a bit down, and gives her some advice that levels aren't that important, though this secretly irritates Ruiko. The next day, Ruiko stumbles upon someone being conned by three thugs over Level Upper and can't bring herself to just run away, so she confronts them. Kuruko coincidentally arrives before Ruiko gets hurt and subdues two of the thugs, but has trouble using her teleportation powers against their boss, due to his ability to distort light affecting her teleportation. He chases Kuroko throughout an abandoned building, but is defeated when Kuroko teleports the windows to cut through the building's supports, bringing the place down. Having barely just survived, the thug surrenders his Level Upper to Kuroko. Ruiko feels even more conflicted about what to do with the Level Upper, but an encounter with some of her friends leads her to tell them that she has it.

Ruiko uses the Level Upper on herself and her friends and is happy to have an ability. Meanwhile, Kuroko takes care of more Level Upper offenders and gains more injuries in the process, keeping them a secret from Mikoto. Remembering when they ate shaved ice, Mikoto and Kuroko come to the conclusion that the Level Upper is using synesthesia to manipulate brainwaves. Kazari soon hears from Ruiko that her friends have fallen unconscious due to the Level Upper, and later finds her unconscious too. After admitting Ruiko to the hospital, Mikoto feels responsible for hurting her feelings with her advice and wants to help. They later learn from a frog-faced doctor (Heaven Canceler) that the Level Upper victims seem to share a brainwave pattern with someone. With the help of Mii, they theorize that Level Upper actually connects ability users like a network and learns the culprit is, to their surprise, Harumi. Kazari, who had visited Harumi earlier and discovered her notes on synesthesia, is taken hostage by her. Noticing Kuroko's injuries, Mikoto decides to rescue Kazari and stop Harumi by herself.

Harumi explains to Kazari that she used the Level Upper Network as an alternative supercomputer as she wasn't allowed to use the Tree Diagram supercomputer. She assures Kazari that she will release everyone once she's done, giving her a cure program. When she is roadblocked by the AntiSkill, she uses the Level Upper's Administrator power; Multi-Skill, to utilize the abilities of the victims to defeat them. Mikoto arrives and battles Harumi who blocks her every attack until she lets her guard down, during which Mikoto gets close enough to shock her. In the process, Mikoto experiences flashes of Harumi’s memories. In the past, Harumi was assigned by her boss, Gensei Kihara, to be a teacher to a group of Child Errors to prepare them for an experiment, growing fond of them in the process. However, the experiments went horribly wrong and the children ended up in comas, with Kihara deciding to cover it up. Harumi explains she wanted to find a cure to save her students by using Tree Diagram, but was denied every time which led to her creating the Level Upper Network. Her anger soon causes her to lose control of the network and fall unconscious, and a strange fetus-like creature emerges from her head.

Mikoto and the AntiSkill fight back against the creature but it only causes it to regenerate its wounds and grow bigger as it heads towards a nuclear power plant. With the network out of control, the comatose Level Upper users starts screaming in pain. Realizing what has happen, Harumi explains the creature, called AIM Burst, is the result of the 10,000 Level Upper user's AIM fields and their negative thoughts. With the help of AntiSkill members Aiho Yomikawa and Tsuzuri Tessō, Kazari manages to upload the cure Harumi gave her, a song file, which is played all over the city, calming the Level Upper users and weakening AIM Burst. Despite losing its regenerative ability, AIM Burst is still able to use the Level Upper user's powers and emits their negative thoughts to Mikoto and Harumi. Mikoto battles AIM Burst again and apologizes to the users for not understanding their feelings and tells them not to give up on their dreams before shooting a railgun to destroy the creature's core. As sunset arrives, a mysterious woman and her team inspect the damages at the power plant while Harumi is arrested by the AntiSkill, still hoping to find a way to cure her students. Kazari later meets up with Ruiko who, having recovered from her coma and lost her powers, apologizes to her for forgetting what was truly important.

Big Spider Arc
Mikoto becomes involved with Judgment's investigations with the rise of Skill-Out attacks by Big Spider on espers, on Kurozuma Wataru's orders (actually Hebitani Tsuguo). She later meets Kurozuma Wataru the true leader of Big Spider, looking upon dreamily upon the moribund Strange. Much later, Mikoto and Kuroko discover Tsuguo's base and decide to take them all in, however, they are depowered by the use of Capacity Down. They are later saved by Wataru, who reveals that he has returned, prompting Tsuguo and his group to flee. Konori Mii, later appears before Wataru before he leaves, and calls him her senpai. Confused, Mikoto and company later visit her apartment to talk to her, and meet her roommate who reveals that Mii was a member of Big Spider. Mikoto remains confused on why Mii seems to hesitate in choosing the present over the past, and later confronts her in an old Big Spider, and ask her if she is going to tip-off Wataru regarding the Anti-Skill on the Strange. Wataru later appears before them, hither, Mikoto bears witness to Wataru urging Mii to move on.

Mii decides to choose the present, and Mikoto and Kuroko give her red jacket to wear as rememberance to her past. Mikoto later joins Kuroko, Mii and Wataru on the final assault on the Big Spider. She later destroys Capacity Down, and with Kuroko, see Mii and Wataru finally disband Big Spider. Mikoto later witnesses Kurozuma's arrest by Mii.

Poltergeist Arc
Kazari gets a new roommate, a transfer student named Erii Haruue. As Mikoto and Ruiko hang out with Erii, Kazari, Kuroko and Mii attend a joint AntiSkill/Judgment meeting held by Therestina of the Multi Active Rescue(MAR) Squad concerning earthquake-like "Poltergeist incidents" caused by multiple espers suffering from RSPK syndrome as a result of temporarily losing control of their abilities simultaneously. While Judgment are ordered to only debunk the rumors, Mii decides to do some investigating. Meanwhile the girls decide to celebrate Erii's arrival by attending the local Hanabi festival. As Erii starts to reminisce about her past with her new friends, she suddenly goes into a trance and wanders off on the hill their on. Kuroko soon gets a call from Mii who reveals these Poltergeists are not natural but were created on purpose. At that moment, another Poltergeist event occurs over where the girls are. Kazari tries to protect Erii from a falling lamppost but both are saved by Therestina in a powered armor. As the girls come to grip on what has happen, below the hill, a familiar woman is seen in the crowd.

Sisters Arc
The Railgun manga greatly expands upon Mikoto's actions during the Sister's arc. The first clone she meets is Misaka 9982, and she forms somewhat of a bond with the clone. After she witnesses Accelerator kill Misaka 9982, Mikoto attempt to avenge her death, but she fails. Mikoto attempts to stop the project by destroying the research facilities, and even has a confrontation with ITEM during her quest. Despite the destruction, the project continues. As in the Light Novels, Touma helps put an end to the project.

There is also an extended epilogue to this arc in the manga, where she recruits Saten's help to make cookies for Touma, but she is ultimately unable to.

Silent Party Arc
The arc serves a vehicle to force Mikoto into a situation where she is powerless just like in the Sisters Arc despite her power. However, it is used as a way to show her humbled attitude towards the dark side of Academy City, the limits of her powers despite being a level 5, and a way to involve her friends in helping her, similar to the Poltergeist Arc.

This is through Febrie, a Chemicaloid, an artificial human. When first introduced, she is suspicious of Mikoto, to which she is forced to try to gain her favor. This occurs after she saves her from the Security robots that were controlled by Diffusion Ghost by STUDY, the antagonistic organization in the arc. Febrie's circumstances are not unlike that of her clones, and her efforts to act sisterly towards her is commented upon by other characters like Mii, Ruiko, and Kazari while they were in the public bath.

When Mikoto realizes that Febrie's circumstances goes deep into the dark side of Academy City, a world she is acquainted with. She initially tries to go out alone, with Kuroko supporting her once again knowing that she will once again do something on her own. It is not until she contemplates Kongou Mitsuko's words regarding friends, that she is forced to acquiesced to ask for help, where everyone jumps at the call despite Mikoto saying that she has no guarantee she can protect all of them. She later meets up with Therestina Kihara Lifeline again. Ever a difficult person to deal with, Therestina constantly mocks and belittles Mikoto, and even moreso when she hears her asking for her help as she is familiar with the dark side. Therestina asks if she despises the city after discovering the truth within it, to which Mikoto says she doesn't because she has met good people in the city as well, which annoys Therestina. After much whining from Mikoto, Therestina finally acquiesces to Mikoto asking about artificial humans, telling her of Chemicaloids she used to hear of. She then says that those who have created the Chemicaloids are planning to show it to the city in an upcoming event, which Mikoto discovers is the Academy City Research Exhibition Assembly. Therestina, however, warns her that even though she can easily use the fact that she is a Level 5, a valuable guinea pig to the City, she knows not how deep the darkness of those who are not even considered guinea pigs.

After the girls discover one factory owned by STUDY, Mikoto goes there on her own, and has Kuroko on stand-by, to search for the neutralizer that would keep Febrie alive. While going there, she notices the bridge where she and Touma had often meet, and where she confronted and attacked him. Here she recalls on how Touma was being forceful in having his dream of achieving a happy ending where nobody is dead, though she keeps it mind. She later meets Shinobu there, who gives her the recipe for the neutralizer, as well as Aritomi Haruki, leader of STUDY. Here, he reveals that the data now in Mikoto's hands is a dummy, a part of his additional safety measures to keep vital information from leaking out. Now that Haruki has discovered that Shinobu is a traitor, he forces her to make a painful decision — to help detain Mikoto so that she can guarantee the safety of the recipe for the neutralizing agent she needs to keep Febrie alive. Although Shinobu is hesitant to do it, Mikoto tells her to push on for Febri's sake. Shinobu stabs Mikoto with the injector as she requested, despite having the strength and numbers to overpower Haruki, and thus Mikoto instantly collapses due to the effects of the drug. However, much to the shock of the two girls, Haruki destroys the precious data in front of them.

With Mikoto no longer a threat to Haruki, he decides to talk to Shinobu and Mikoto about his actions. Haruki clarifies that Febrie's well-being is not important as she was just a spare for the greatest invention of STUDY Corporation, which they call "Janie". Haruki also relates to Mikoto his life story, recalling his achievements in the Academic Assembly and his frustrations as a scientist whose efforts are dwarfed by those of the espers of Academy City, both of which motivated him to initiate the Chemicaloid Project. Eventually, Mikoto succumbs to the drug injected into her by Shinobu and passes out. Haruki later has her and Shinobu transferred to an office space somewhere nearby. Here, Shinobu tells Mikoto on how she ended up with STUDY. Here, Mikoto thanks Shinobu for helping her Sisters and tells her as well of the despair that she had felt during the Sisters Arc that only was alleviated because of her friends, whom she has now come to rely on. As her friends arrive to bust Mikoto out, Shinobu opts to stay behind as so that she can keep a look out on Janie and finally asks Mikoto to save them.

Back in the office, Mikoto relates vital information regarding finding Janie, in which Febrie can track her own sister if she uses her powers, like when it takes control of the Powered Suits used by STUDY. They later discover that not only Anti-Skill unable to help, they are up against 20,000 and more Powered Suits by STUDY. Seemingly hopeless, Mikoto recalls Touma's speech to her, which gives motivates her. Mikoto is later with Febrie at the crack of dawn and the beginning of STUDY's Silent Party. Using Febrie, she narrows down STUDY's location. She defeats countless Powered Suits, and but STUDY tries to sic mobile weapons equipped with a gun that mimics Mugino Shizuri's Meltdowner to stop her. However, she is later aided unintentionall by Shizuri herself and ITEM, wanting revenge on STUDY.

Haruki is soon confronted by Mikoto and Febrie as they reach his main console room. With his plans in the Academic Assembly falling apart, Haruki decides to resort to drastic measures, shutting down Janie's link with the many Powered Suits outside to turn Janie into an unstable entity and then ending his life. But, Mikoto was able to stop Haruki from committing suicide, although Haruki later admits that his "last resort" was irreversible. Haruki's colleague, Sakurai Jun, explains to her that they are in a grave situation, as Haruki's last resort involves releasing thousands of filaments from a missile fired 35,000 kilometers above the Earth, and the rampaging Diffusion Ghost will cause widespread AIM diffusion field interference that will affect each and every esper in Academy City. With the AIM bomb coming, Mikoto makes a conference with her friends to try and find a way to stop the bomb. She entrusts Febrie to Shinobu's care, now determined not to stand idly by and do nothing. The Sisters later contact her and offer their assistance. They are the ones who calculate on what to do in order for the Ekaterina II S mecha that was brought into the battlefield. As Mitsuko and Awatsuki Maaya prepare the mecha, Mikoto and Kuroko are in the cockpit. Here, Mikoto apologizes to Kuroko for involving her, to which she replies that she doesn't mind for she is finally fighting side by side with Mikoto. With that, they are launched into space by Mitsuko's Aero Hand. Kuroko becomes visibly sicked upon arriving in the upper atmosphere, but manages to teleport away as Mikoto begins to do her part. Mikoto then uses her power to make the mecha as the ammunition for her Railgun, the force of which was enough to destroy the AIM bomb. Kuroko teleports an exhausted Mikoto back to earth after she destroyed the AIM bomb. As the Academic Assembly begins in earnest, Mikoto sleeps at the assembly grounds, alongside Kuroko, Kazari, Ruiko, Mitsuko, Kinuho, and Maaya.

As Janie and Febrie are in a Kongou Airlines runway, preparing to leave to the outside for body readjusments, Mikoto talks to Shinobu once again, expressing her shame on how she had to leave so soon just as they've become friends. Here, Shinobu notes on how the digital records for what had transpired in the Silent Party was altered to give them a positive look, as well as the fact that some of the authorities have suspiciously seem to have their memories altered. Here, Mikoto flounders about, seemingly confirming that despite her distaste for Misaki and her powers, she lays down her pride (among other things) and ask Misaki for help. And thus, the fellowship, though bound by friendship and love, part ways.

Daihasei Festival Arc (Railgun)
Follows Misaka's encounters during Daihaseisai. Competing in pair race with Kongou Mitsuki, observing her clone in the ball knockout. She meets Touma and he buys drinks for them when Misaki interupts and Touma and Misaki share a joke about how she is always being "biri-biri" or "piri-piri" towards them. She later comes to save Saten when she is caught looking for Shadow Metal, and mistakenly attacks the groundskeepers.