Appearing as a cylindrical piece of stone, she was originally a girl that was transformed by Marian Slingeneyer to represent the Throwing Hammer of Thor in Norse mythology. She is the first actual member of GREMLIN to be introduced in the story. She is a magician who has her body optimized into various forms of the hammer.
Despite being called "The Hammer," Mjölnir has various shapes but her first and most prominent appearance is that of a cylinder made of heavy stone with a diameter of 55 cm and a height of about a meter. The other forms were a sphere, a cube and finally a flat plane in the shape of a cross into a hammer. Mjölnir appears to communicate and recite spells by having countless sets of human lips both large and small appeared on its surface.
The magician apparently gathered up a lot of power for an unknown reason only to have lost it in the shift of power during WWIII. With the reason to obtain strength gone, Mjölnir continued to gain power and go on a destructive path. Marian Slingeneyer, another member of GREMLIN, is responsible for her current form as a cylinder. 
Shinyaku Toaru Majutsu no IndexEdit
- Main article: Homecoming Arc
Mjölnir appears on-board the Radiosonde Castle as its guard and controller for dropping onto Academy City. Due to Mjölnir's inability to cope with failure, one-third of the Castle was destroyed when the technique of "throwing hammer" was unleashed. She was later thrown off the structure when Kanzaki Kaori used an anti-flight spell on her.
Hawaii Invasion ArcEdit
- Main article: Hawaii Invasion Arc
Her next appearance is in the aftermath of GREMLIN's invasion of Hawaii, where she is summoned shortly after Marian Slingeneyer uses her new cellphone, from there on she is seen accompanying Marian Slingeneyer while she converses with Othinus. Here, she is used against Cendrillon, who despite her speed, is quickly defeated by Mjölnir's long range attacks.
Apparently here, she was used to take in the and control the volcanic energy from Kilauea, to be used as a furnace for the creation of Gungnir.
Ichihanaran Festival ArcEdit
- Main article: Ichihanaran Festival Arc
Eve of the FestivalEdit
In the eve of the festival, Mjölnir appears alongside Marian and Thor in Academy City, in order to collect Fräulein Kreutune for Othinus. Here, while Marian is completely listless after the death of Bersi back in Baggage City, Mjölnir clatters and shakes, expressing her worry towards Marian's attitude, and her dismissal of Thor's instruction on not making pre-emptive attacks.
After Fräulein escapes the Windowless Building due to Touma and Thor's efforts, Marian still remains in the bench she was resting on, but notices that the Anti-Skill are on high alert. Marian ponders for a moment and asks Mjölnir what they should do, before ultimately disregarding it as too much of a hassle for her.
Marian finally takes action after receiving a lot of information regarding the disturbance in Academy City being related to Fräulein. She asks Thor to handle as she is unsure if she nor Mjölnir can handle her, much to the latter's chagrin. Thor tells Marian to meet up with him in a plaza in front of the District 7 station in order to have more firepower in capturing Fräulein. As Marian tries to search for Thor, she discovers a poster of a bulletin board declaring her to be a dangerous person involved in Baggage City, and that she should be reported to Anti-Skill. In truth, this was a gambit that Touma formulated, by making GREMLIN think that Academy City and Ollerus are attacking them, and Ollerus think that Academy City and GREMLIN are attacking his group. And to finish charade, Thor transforms into Marian for Touma use his picture to post in a public bulletin board, which Thor will direct Marian to. Marian tells Thor that they will have to move to a different hideout in order to take the time to analyze the situation, and she is forced to search for an abandoned building as her posters are up everywhere in the hotels, with Mjölnir following close behind.
Mjölnir is apparently unaware that Touma was following Marian in order to draw out the scout, and activate the second phase of his trap.
During the FestivalEdit
Mjölnir is present when Thor and Marian notice the shock waves of the battle between the reformed Kakine Teitoku and Accelerator. Marian becomes genuinely curious of the events happening, wanting to investigate the goings-on in the city. Marian orders Thor and Mjölnir to make a scene as so she can start gathering people as materials. Seeing as he is the only one who could stop her, Thor first asks Marian who she thinks is causing all the ruckus, to which she replies that she doesn't know and simply gives out some logical assertions. Thor tries to convince Marian to wait and then attack when they expose themselves, he tries to convince her that it may not be involved with them, and at last, tries to convince her through telling her that she might reveal her location. But Marian would not yield to Thor's reasoning's, telling him to stand down and find a new hideout as he has yet to be known by their enemies compared to her. Thor gives up in convincing her, and just kicks her, making her unconscious. After felling Marian, Mjölnir is angered and prepares to attack Thor. Thor however states that Mjölnir attacking would put Marian in danger, one of the key components in Othinus' plans, which would fall into ruin upon her death. This is a fact that Thor specifically mentions to Thor would be beneficial for Ollerus, who would then find no need to kill Fräulein Kreutune, and convinces her not to let Marian out. With that Mjölnir's wrath is slain. Thor says that he will look into how much information Ollerus' group has and what kind of traps they have in store, and states that Mjölnir should prepare so that Marian can escape. As a final measure, Thor tells Mjölnir that if there is something dangerous, she can throw Ollerus' group off by roasting an entire city block. With that, Thor leaves Mjölnir.
As she is of course represents the weapon of Thor of Norse mythology, she is later used by Thor himself. Mjölnir is used remotely by Thor. She connects to Thor and gives him a supply of energy, significantly increasing his power. He first uses Mjölnir in his battle against Silvia, and later, in his battle with Touma.
After the failure of capturing Fräulein Kreutune, Mjölnir joins Marian to leave Japan in Tokyo Bay, clattering about and supporting Marian's arguments. Here, they witness the punishment of Thor (actually Ollerus secretly in disguise) at the hands of Othinus, after giving her the organs of the original Kakine Teitoku to compensate for their failure.
Magic God Othinus ArcEdit
- Main article: Magic God Othinus Arc
She is assigned by Othinus to assist Marian while producing the lance. As such, Thor (Ollerus in disguise) cannot use her and instead he is instructed by Othinus to head out as Almighty Thor and guard the perimeter while they are completing the lance.
GREMLIN invasion of TokyoEdit
- Main article: GREMLIN invasion of Tokyo
While battles are going on, Othinus, Marian and Mjölnir stand at the side of a large pool filled with a thick transparent liquid which is actually pure gold that lost its chemical properties and meaning. Othinus then wonders that the sight before her is what it’s like when beginning the production of the lance. Marian then explains it to her and assures Othinus that all they have to do is to wait once the process starts, to which Othinus that she won't let her guard down until it passes a certain stage. She then mentions that what they are doing is essentially a magic ceremony but cannot be completed solely with magic since the automatic work will stall somewhere. To accurately throw in the holistic esper and continue the ceremony with the proper timing, it needs to be switched over manually. Here, the volcanic energy Mjölnir gathered from Hawaii is used to ignite the pool, the furnace needed to create Gungnir.
When Ollerus finally reveals himself, a great roar exploded out, which came from Mjölnir who is connected to Thor. At that time, Mjölnir is assisting Marian in completing the lance. Ollerus doubts it himself that the explosion is not enough to kill them, though he is later proved true.
Shifting and Fluctuating WorldEdit
In the final recreation of the world by Othinus created specifically to break Touma's spirit, known as the Version_Omega world in-text, where several characters from the original world have been "saved" or have not experienced great tragedy, people from the magic side like nuns are allowed to enter Academy City, and seemingly have no complex against science. Notable here is that Mjölnir still retains being a cylinder block. Thor, Marian, and Mjölnir are first seen by Touma right after believing that looking at all the people that he is familiar with in the "perfect world" would get rid of his regrets as he tries to decide on how he should have himself killed. Marian is apparently in a rush for the festival that is happening, to which Thor says that the festival had just started, as such there will be tons of people. He then suggests that being late would be perfect. Marian does not reply but says that she has spotted Bersi and that he is secretly with the ringlet curl maid (Kumokawa Maria), apparently mad. Thor is awed by this, then says that it is Bersi's decision, but says that she should pay attention to Mjölnir as she is shaking in jealousy.
VS the WorldEdit
Marian and Mjölnir survive the attack by Ollerus in Sargasso and discovers that Othinus has left with Touma, betraying GREMLIN. In great anger she uses Hrímfaxi to get to Denmark, as she was a part of GREMLIN she could guess what Othinus was thinking. This action made quite a show and is noticed by the other members of GREMLIN.
At the height of the manhunt for Othinus and Kamijou Touma, they are in the city of Støvring and while they are on their way to their next destination which is Billund, the long-distance truck carrying them later stalls out. They then decide to go to a gas station nearby in order to buy a new battery rather than walking to their next destination. As they are about to leave the area after getting what they needed in the station, the gas station is suddenly split in two. They try to escape the area before it blows up but suddenly meets up an Marian Slingeneyer Mjölnir. Othinus recognizes them after Marian asks her if she still remembers them.
Mjölnir is just watching in the sidelines all throughout Marian and Touma's fight. Othinus spots her in the battlefield and asks what is she doing there. After the battle is over, Othinus notices that Mjölnir suddenly disappeared.
At the end of Touma and Marian's battle, Mjölnir realizes that despite the fact that Marian altered her body as it is, she didn't view it anything out of the ordinary and she had given her body to Marian because she was a trusted friend and that was all there is to it. As Touma sits on the snowy plain with Marian lying next to him, he calls Mjölnir and asks if she was going to fight him too. Mjölnir shakes her body as if saying no then picks up Marian. Touma then asks Mjölnir on what she is about to do now, to which Mjölnir didn’t respond. Touma then writes his cell phone number on a piece of paper and sticks it in the pocket of Marian’s overalls. He then tells Mjölnir that he is busy with Othinus right now and that if they need something they should tell him and he will stand by their side next time. They then walk towards their own separate destinations..
As Mjölnir is associated with Thor, the Norse god of not only thunder but that of agriculture, weather, and terrain. As such, her form symbolizes his power as the convenient tool that could be used for many different tasks and can be viewed as a magic wand of sorts. Mjölnir represents the vestiges of his power over agriculture and farming before he became a mere god of thunder in Norse mythology. She is not only a magician but a spiritual tool that can be used for anything. She is described as being a rare existence, that the entire magic side could easily fight over her.
- Strong enough to take a kick from Kanzaki Kaori without any relative problems.
- Movement at high speeds.
- Deployment of magical weapons of a crossbow and matchlock pistols firing projectiles at supersonic speeds just less than Kanzaki's top speed.
- The Throwing Hammer - Using the concept of swinging the hammer, the blast of concentrated energy is brought down literally disintegrating everything in her path; this technique rivals even mobile fortresses.
- Thunder and Lighting
- Hammer of Thor - Thor can borrow Mjölnir's power by making a link with her, apparently regardless of distance, significantly increasing his power.
- Absorption of volcanic energy: She can also absorb, store, and exude volcanic energy, making her of the most important components in the creation of Gungnir. It is unknown if she can absorb other forms of energy
|Cendrillon||Saronia A. Irivika|