|Relatives|| Unnamed Father (Deceased) |
Unnamed Mother (Deceased)
Mr. Arlert (Grandfather, deceased)
|Former Affiliation||104th Trainees Squad|
|Grad Rank||Outside the top 10|
|Manga||To You, 2000 Years From Now|
|Anime||To You, 2000 Years From Now|
|Anime|| Marina Inoue (Japanese)|
Josh Grelle (English)
|Someone who can't sacrifice anything can never change anything!|
Armin Arlert (アルミン・アルレルト Arumin Arureruto?) is a childhood friend of Eren Yeager and Mikasa Ackerman, and is one of the two deuteragonists of the series. Although he appears to be the physically weakest of the 104th Trainees Squad, his high intelligence and strategic genius make him an invaluable asset, especially when paired with Hange Zoë's mind.
AppearanceArmin is rather short for his age with a small build. Armin has a round face, framed by his blond hair, with large, expressive blue-eyes and a pudgy nose.
In his childhood, Armin wore a long-sleeved single-buttoned jacket with a collared shirt, long dress-pants and dress shoes. As a member of the 104th Trainees Squad, Armin wore the standard 104th Trainees Squad uniform. After graduation into the Survey Corps, he wore the standard Survey Corps uniform. Underneath his short brown jacket, he wears a white and collared button up shirt, similar to the one he worn as an adolescent. Like his fellow comrades, Armin accompanies his attire with a large green cape when participating in the 57th Expedition outside the Walls.
Growing up, the naturally curious Armin had a deep fascination with the world beyond the Walls, and even enthused his best friend, Eren, into sharing this passion. Much of his free time was spent reading any book about the outside world he could find, but he would be branded a heretic for his unusual interest, and was frequently picked on. Too timid to defend himself, Armin would often need to rely on his friends to protect him from local bullies. This, coupled with his frail physique, was a source of much shame for Armin, leading him to have poor self-esteem and believe himself to be a burden upon others. Because of this, Armin was very eager to prove his worth, with his ambition being to one day stand on equal footing as his friends.
Armin is exceptionally loyal and selfless, constantly worrying for the safety of his friends, and ready to throw himself into dangerous situations for them; even offering to sacrifice himself for Mikasa. When he, Jean, and Reiner had to decide who would be left behind without a horse, Armin immediately offered himself without hesitation. And when Jean was injured in battle, Armin rushed to his aid, placing himself in danger as well. Armin is also very level-headed, keeping Eren and Mikasa under control when their emotions get the better of them. He has talked down a fight Eren started with a soldier, and restrained Mikasa from acting rashly during Eren's military trial.
Although initially meek and a bit cowardly, Armin acknowledged these weaknesses, letting his potential shine brighter as he gradually gains more confidence in himself. Relieving himself of doubt, Armin has shown great investment in humanity's future, always striving for and thinking on how he can change things for the betterment of mankind. However, Armin's life has also left him considerably jaded, and he has come to believe pragmatic actions and great sacrifice are necessary for change. Armin admires strong leaders such as Darius Zackly, Ian Dietrich, and Dot Pixis for their ability to sacrifice themselves in order to put humanity further. Armin's most consistent traits remain his kind heart and keen intuition, making him often concerned with the group's morality.
Before Year 845
Armin originally lived in the Shiganshina District of Wall Maria with his parents and grandfather. Armin's parents (and in the manga his grandfathers book) instilled in him a passion to travel beyond the Walls and see the outside world. In the anime, several years before the fall of Wall Maria, Armin's parents are said to have escaped beyond the Walls. Armin was then solely raised by his grandfather until after the fall of Wall Maria. Alternatively, in the manga both of Armin's parents are never said to have gone beyond the walls and are also present until the fall of Wall Maria, along with his grandfather.
Both Armin and Eren were stuck together as outcasts from the other children in town. Armin's friendship with Eren only began when he showed Eren his grandfather's book about the world beyond the Walls.Armin would often spend his time enthusing Eren about the world beyond the walls, for which Armin held a passionate curiosity. Reading from his grandfather's book about salty oceans, deserts and other surreal places, Armin expressed a desire to one day venture out and see these magnificent sights for himself, and also inspired Eren to dream of freedom beyond the safety of the walls.However, Armin's interest in the outside world was met with frequent harassment by local bullies, who regarded him as a heretic.
In the year 845, Armin would once again find himself cornered by bullies who mock him for his curiosity for the outside world. Refusing to fight back, Armin would need to be rescued by the timely appearance of Eren and Mikasa. Later, he and his two friends settle by the riverbank, where Eren broods over his desire to join the Survey Corps. Just as Armin muses how the walls can't protect humanity forever, the Colossal Titan appears and subsequently breaches Wall Maria as Armin and the others watch in horror. As Titans flood the Shiganshina District, Eren and Mikasa head back home to find their doomed mother as Armin tries to stop them, but finds himself petrified by fear. Unbeknownst to Eren and Mikasa, Armin was the one to locate and inform Hannes to save the two as they were going too close towards the Titans' direction. Armin makes it aboard an evacuation ship with Eren, Mikasa and his grandfather, and witnesses the Armored Titan's appearance. One year later, Armin's grandfather- as well as many other refugees of Wall Maria- are sent on a recovery mission beyond the safety of the wall. Armin however, knows this to be a false tactic to reduce the population. However, originally in the manga both of Armin's parents are never said to have gone beyond the walls before the fall of Wall Maria, and instead are also sent on the recovery mission to their supposed deaths in the year 847, along with his grandfather. As a result, Armin harbors resentment for the government.Armin is then left alone and orphaned with Mikasa and Eren, where he decided to join the military.
No longer content with sitting by in the face of the Titan threat, Armin decides to enlist into military training along with Mikasa and Eren. He was able to pass the basic aptitude test after some effort, and tried to help Eren with it when he struggled to stay upright.Although high in intellect, Armin was considered weak in physical strength, and graduated below the top ten.
During the night after their graduation and before the trainees had decided on their chosen section of the military, (Military Police, Wall Garrison, or Survey Corps,) Armin sits with Eren and Mikasa to eat, and watches as Eren responds to a taunting Jean, by finally deciding to set the record straight and gives a moving speech to the whole of the 104th trainees on how he wants to kill the titans to gain freedom and pursue his dream to see the outside world beyond the entrapment of the walls.
After the dinner, Armin finds Eren and Mikasa sitting outside of the building and joins them, saying that the party is over and that they should head back to the dorms. Before they do, Eren asks Armin which section of the military he will be joining. Armin sits down and reveals that he will join the Scouting Legion along with Eren and Mikasa. Eren questions his choice incredulously, knowing of Armins physical weaknesses. Armin affirms his worries by acknowledging that he is physically weak. Eren responds supportively but advises Armin not to join Erens own crazy course of action while neglecting his own strong points. Armin responds bitterly determined, saying that he'd rather die than become a burden.
Before Eren or Mikasa can answer, they are interrupted by seeing Hannes, who they now salute as the captain of the Wall Garrison. Hannes points out that its been 5 years since he's seen them. He then mentions that he still has no idea where the missing Dr. Jaeger even is, and that Eren is possibly the only one with memories as to his whereabouts and asks him of he can remember anything. Eren then collapses, worrying Hannes, Armin, and Mikasa who he tells that even though this happens to him, he is still unable to remember.Trost. He trembles in fear, realizing how sorely unprepared they are to respond, but Eren manages to shake him out of it. Later, Armin joins Eren's squad in the middle guard of Trost and exchanges confident words with Eren about killing Titans, and soon after departs with Mina Carolina, Thomas Wagner, Mylius Zeramuski, and Nac Tius to their assigned location. Along the way, Thomas is caught by surprise and eaten by an abnormal Titan. Enraged and vengeful, Eren charges ahead of the others to engage the Titan, and Armin and the others follow suit. However, the group is ambushed and picked apart by the surrounding Titans, leaving only Armin alive and Eren missing his left leg. Shocked and horrified, Armin is left immobile as a nearby Titan plucks him up and attempts to swallow him. Eren, just barely conscious enough to remember how Armin inspired him to see the outside world, leaps to Armin's aid; just barely saving him from being swallowed. Eren hurls Armin out of the Titan's mouth, but is eaten in his place as Armin screams in anguish.
Stuck in a state of shock for some time, Armin is shook out of it by Connie who questions where the rest of his squad is. Armin suffers a mental breakdown, despising himself for his cowardice that resulted in Eren's death. He leaves to inform the rear guard of what happened, along the way lamenting how the world is and always has been hell. On the way, he encounters Hannah trying to resuscitate Franz. Armin beckons Hannah to stop, seeing all too well that Franz is bisected and already dead.
Armin is later confronted by Mikasa above the rooftops with the other stranded trainees. She questions him about Eren's location, but as soon as Armin looks at her with tearful eyes she understands. Armin blurts out the names of all the fallen soldiers in Eren's squad, ending with Eren himself. Despite his clear regret, Mikasa calmly comforts Armin and explains that they mustn't get emotional at a time like this. Armin follows as Mikasa guides the leaderless trainees to safety, but realizes how she is only masking her distress. When Mikasa carelessly uses up all of her gas, Armin comes to her aid. Soon after, Armin, along with Mikasa and Connie, witness the appearance of the mysterious Titan who only kills other Titans.
With Mikasa's gas is exhausted, Armin provides her with all the remaining fuel and blades he has, seemingly ready to remain behind. Armin requests to keep one blade, implying to commit suicide with it, but Mikasa and Connie refuse to leave him behind. With Trost's military headquarters overrun with Titans, and the soldiers running low on fuel, Armin devises a plan to lure the Rogue Titan towards the HQ to wipe out the surrounding Titans. Once inside the HQ, Armin constructs a plan to eliminate the Titans infesting the supply depot inside. While Armin and several other soldiers act as bait, members of the 104th's top 10 would slay the seven Titans without having access to their maneuver gear. Armin's strategy works, and the trainees refuel their gear. Shortly after, Armin witnesses Eren mysteriously emerge from the Rogue Titan's nape, unconscious, but alive.After being recovered, Eren was detained by a group of soldiers and was going to be executed. Armin and Mikasa defend him, as he wakes up surprised and confused. Eren plans to escape over the walls unless Armin is able to convince the soldiers of Eren's value to humanity. Eren tells him that his quick thinking has saved him and Mikasa before, as he was the one who went to Hannes when Shiganshina was being attacked. Armin, more confident than ever, walks into the open and tries convincing the soldiers of Eren's strategic and tactical importance in turning the tide of the battle in Trost. As a soldier, he passionately declares to be ready to die for this cause and makes a grand salute. Pixis, noticing his determination and passion, prevents their execution.Now with a boost in self-confidence, he tells the senior strategists that Eren could carry the boulder over to the hole while other soldiers could lure the Titans towards the walls. They proceed with the plan. Later, when Eren loses control of his Titan form and knocks himself out, Armin rushes to Eren and lands on his back. Remembering the spot where Eren had risen earlier, Armin stabs into him a little askew so that it wouldn't be fatal, but would wake him up. He reminds Eren of his personal vendetta against the Titans, but Eren only becomes responsive once he reminds him of the world beyond the Walls and asks him to think of the reason he wanted to go out there too begin with. Eren, successfully motivated by Armin's words, carries the boulder and plugs the breach and all the remainder of the fighting is from then on supported by the newly returned Survey Corps.
Armin is then present as a witness to the hearing that decides Erens fate as now being revealed Titan Shifter, which ultimately decideds for him to be placed in the custody of the Survey Corps's Captain Levi. He and Mikasa are then separated from Eren until they are able to join the Survey Corps.
Before the trainees are able to decide their chosen military paths, the news spreads that two captured Titans, Sonny and Bean, were slain, and Armin along with other trainees from the 104th Trainee Squad are called in for inspection. Armin, Annie, and Connie discuss which branch of the military they would join. To the surprise of Connie, Armin declares he intends to join the Survey Corps. Annie compliments Armin on his courage, but states she still wants to join the Military Police and survive. To Annie's surprise, Armin tells her she is also good person because he can tell she doesn't want them to join the Survey Corps either. She disagrees saying that she is not a good person, because she just wants to assure her own survival by joining the Military Police.
After joining the Survey Corps with Eren, Mikasa and the rest of the 104th's top 10 (excluding Annie Leonhart), Armin participates in the Survey Corps' 57th expedition, venturing beyond Wall Rose. Not long into the expedition, Armin's squad encounters the Female Titan, which is seemingly highly intelligent and knowledgeable about the Military formation. The Female Titan kills Armin's entire squad, but spares Armin's life after carefully removing his hood and observing his face. As the Female Titan moves on, Reiner and Jean meet up with Armin and the three pursue the mysterious Titan. Armin suggests the Female Titan, like Eren, is a shifter and is likely hunting for Eren. The three attempt to engage the Female Titan, and are nearly killed, but manage to stall her, though she immediately beelines for Eren's direction after warding Armin's group off.
Though they survived the encounter, Armin, Jean and Reiner are left stranded with only one horse, which is only strong enough to carry two at a time. After being bandaged up by Reiner, Armin offers himself to be left behind, but luckily, Krista quickly arrives with two spare horses in tow.
Reaching the Forest of Giant Trees, Armin and his fellow soldiers perch on its many high branches, distracting Titans while Erwin confronts the Female Titan. While they wait, Armin concludes that Erwin withheld vital information from most of the soldiers out of fear of traitors existing amongst them. Jean criticizes his commander's actions, but Armin defends Erwin, stating that playing it safe will not bring about change. When the expedition ultimately ends in failure, Armin safely returns to Wall Rose with the remainder of the Survey Corps.
Some time later, in Stohess District, Armin locates and asks Annie, as a Military Police member, for her help in hiding Eren as they need to flee Wall Sina to avoid Eren's inevitable execution. Although initially hesitant, Annie accepts, and Armin explains that they must smuggle Eren out of Wall Sina by foot and will take an underground route. As he, Eren and Mikasa enter the underground, Annie refuses to continue on, realizing that Armin has led her into a trap. Armin confronts Annie, questioning why she was in possession of Marco Bott's 3DMG during gear inspection. Annie claims that she simply found it, but admits to have killed the two captured Titans using her own gear when Armin accuses her of such. Annie questions why Armin did not take action if he was already so suspicious of her, but Armin states he simply could not believe it, and questions why Annie chose to not kill him when she had the chance. Annie isn't sure herself, but congratulates Armin on managing to corner her, confirming her identity as the Female Titan-shifter.
Armin fires a sound grenade, signalling hidden soldiers to restrain Annie. Despite their efforts, Annie succeeds in injuring herself using a barb hidden in her father's ring, allowing her to transform. Anticipating this, Mikasa grabs both Eren and Armin and takes them further underground as Annie in her Titan form attempts to grasp them. Seeing that his strategy has failed, Armin initiates plan B, trying to encourage Eren to fight Annie. Eren tries repeatedly to assume his Titan form, but cannot due to his reluctance to fight Annie. Having no other option, Armin suggests he and Mikasa distract Annie so that Eren may safely flee. Realizing that if he does not fight, his friends will surely die, Eren finally transforms into a Titan and fights Annie.
After realizing that she is fighting a losing battle with Eren and the Survey Corps, Annie decides to make her escape by climbing over the wall. As Mikasa, Hanji and, other Survey Corps scramble to catch up to her, Armin realizes that they will not be fast enough and instructs Eren in his Titan form to propel Mikasa up the wall, so that she can gain enough speed to overtake Annie.  Mikasa cuts the Female Titan down and Eren pins her to the ground, allowing for the other Survey Corps members to extract Annie from the nape of the neck. When Eren awakens from his Titan form, wondering Annie's fate. Armin informs him that no one knows, as Annie encased herself in rock hard crystal.
As Eren rehabilitates from his ordeal, Armin takes a moment to rest with the others. Armin informs Jean that Eren's summons to the King were cancelled and that Annie is indeed the Female Titan. She's been detained underground after encasing herself in a crystal to avoid interrogation. Reflecting on the mysterious Titans found in the walls, Armin observes that for all these years they were being protected from the Titans by Titans. Armin cannot fathom how the walls were built in the first place, but hypothesizes that abilities like Annie's hardening power were somehow employed to construct the walls.
Armin's hypothesis is later confirmed when the rock sample Squad Leader Hange had picked up from Annie's Titan body matched the properties of the Walls. With this information in mind, Armin and Hange propose a way to repair Wall Maria: Eren using his own hardening ability to mend the breach. Pastor Nick informs the group about a girl in the Survey Corps who may know more about the walls, stating that while he cannot share any more details, she can. Armin and the others immediately recognize the girl in question to be Krista Lenz.
Rescuing Krista, Reiner, Bertolt, Connie and a grievously injured Ymir from Castle Utgard, Armin and the Survey Corps regroup on top Wall Rose. However, Armin shortly after learns of Reiner and Bertolt's secret correspondence with Annie, confirming his and Hange's suspicion that the two are also spies. As Reiner and Bertolt attempt to take possession of Eren, they are attacked and nearly killed by Mikasa, but survive. A horrified Armin is present to witness Reiner and Bertolt's Titan transformations, marking the second and third appearance of the Armored and Colossal Titans, respectively.
Armin is called by Hange to aid Eren as he battles Reiner in their Titan forms, meanwhile the Colossal Titan is kept preoccupied defending himself from the rest of the Corps. Advising Eren to retreat to the wall, Armin provides Mikasa with his spare blades to support Eren against the Armored Titan. With their combined strategic geniuses, Armin and Hange advise Mikasa to cripple the unprotected parts of the Armored Titan's knees, allowing Eren to gain the upper hand. However, just as the battle turns in Eren's favor, the Armored Titan lets out a loud wail, signally the Colossal Titan to throw itself off Wall Rose, landing on the two down below.
Reiner and Bertolt succeed in kidnapping Eren and Ymir in the chaos, and Armin informs Mikasa after she regains consciousness that five hours have already passed since then. Mikasa despairs at the news, but her and Armin's determination are revived upon hearing a rousing speech from Hannes. Joining a force comprised of Survey Corps reinforcements, Garrison and Military Police soldiers all led by Erwin, Armin and the others begin pursing Eren and his kidnappers. Before setting off, Armin implores Krista to stay within the walls, but she insists on joining the effort.
As Armin and the others reach the Forest of Giant Trees where Reiner and Bertolt were resting, they are beset by Titans. Entering the forest with their maneuver gear, Armin's team encounters Ymir in her Titan form. Armin notices Ymir suspiciously surveying everyone and neglecting to respond to anyone. His suspicions were confirmed when Ymir suddenly captures Krista and escapes, realizing that she has sided with the traitors.
Reiner shifts into his Titan form and flees the forest with Bertolt, Ymir and a restrained Eren in tow. Pursuing on horseback, Armin notes that while the Armored Titan is slow, stopping him will be difficult due to Reiner not shedding his joint armor. Eventually, Armin and his fellow trainees succeed in latching onto the Armored Titan where they implore Bertolt to surrender Eren. Just as Bertolt suffers a breakdown, Armin and the others are forced to briefly retreat when Erwin charges into the fray, leading a horde of Titans.
The mass of Titans bring the Armored Titan to a crawl, and Erwin leads his forces into the chaos, seizing the opportunity to secure Eren. Unfortunately, Erwin is bitten and carried off by a Titan along the way, but Armin remains focused on the mission and joins the second attempt to retrieve Eren. Using his gear to climb onto the Armored Titan's head, Armin confronts Bertolt, purposefully taunting him with lies that Annie is being tortured while he and Reiner save themselves. Enraged, Bertolt charges at Armin, but is intercepted by a grievously wounded Erwin who slashes Eren off of him. With Eren secured, Erwin's forces retreat, but their escape is cut off by Reiner who tosses Titans in their way.
Armin is horrified by the risk Reiner is taking, seeing that Eren could easily be eaten. In the struggle, Eren and Mikasa are knocked from their horse, and Jean is incapacitated as he and the others rush to assist them. With nowhere to run, Armin drags Jean towards a small cluster of trees and prepares to face an advancing Titan with only one sword. He looks to Eren and Mikasa, seeing them in just as desperate a situation. The friends exchange teary-eyed glances, preparing for the end. However, Armin is saved when Eren's "Coordinate" power suddenly activates, causing the Titans to attack first the Smiling Titan and then the Armored Titan. This allows Armin to retrieve a horse, and carry a wounded Jean to safety. They retreat from the battlefield, mourning the loss of Hannes, who perished in the chaos, and remembering their childhood with him.
Returning safely to Wall Rose, Jean remarks that the 104th has some luck and Armin agrees by saying that surviving their situation proves it. As Jean wonders what happened to the Titans that were chasing them, he notices a Survey Corps member and Eren lay an injured Mikasa down on the Wall. As the Survey Corps Member begins to detail her injuries like rib fractures Mikasa insists to Eren that she is okay. Eren apologizes and Armin places his hand on Eren's shoulder in a show of support for him. Armin then notices several Survey Corps members attending to Erwin Smith, shouting his name and realizing that he is losing consciousness. As he collapses, the Military insists he be immediately taken away before Eren shouts his concern.
As the wounded are taken away, Jean attends to a shaken Connie by telling him to stand and that everything will be okay. Connie replies that he can't believe he is still alive as Rico Brzenska comforts Historia. Eren grimly remarks that he got captured again and asks how many people got injured because of that. Jean answers that they left with around 100 people and most of the Garrison were eaten due to there inexperience. He mentions that roughly 40 people made it back and of them only about half can stand, including the Survey Corps. He concludes himself, wondering what will become of them all now. Armin tries to soften the situation, saying that they experienced no losses on the way back, with the titans ignoring them and only attacking the Armoured Titan. He mentions the Female Titan being able to draw other titans toward itself, and asks Eren if this time it was him drawing them to the Armored Titan. Jean, looking surprised, asks Eren if he really did control the titans. Eren responds, saying he still does not know for sure. Connie interrupts and asks him if that's true. He realizes himself that that was the reason why the titans headed away from them, and theorizes that if everyone had kept fighting, they would have all died.
Armin continues listening in as Jean speaks to Eren once again, this time of the price they gave up to rescue him, which includes Erwin Smith losing his right arm, Mikasa having her rib cage shattered, Hannes being devoured, and 6/10th of the soldiers dying, and asks if he is really worth such a heavy toll. He finishes himself by saying that it all depends on Eren. Eren gives a soft laugh and informs Jean how he's become quite the preacher since he joined the Survey Corps. Jean rebuffs saying Erens the one who's always hesitant to talk. Connie also remarks how it is weird for Jean to become so serious all of a sudden. Armin contributes, agreeing with Connie. Jean, who is clearly flustered simply tells them that he's the hero who saved Mikasa. After this, Eren thanks Jean, saying it is because of him that he no longer needs to hesitate.
Eren affirms his decision to control the titans, and seal up Wall Maria, as well as capturing the ones who kidnapped him, and making sure that the deaths of everyone are recognized as services to humanity. When Eren concludes himself, Krista attempts to stand up, as Rico and Armin try to persuade her differently. They're interrupted, as Krista reveals her true name to be Historia. She urgently tells Eren that they need to head to the wall.
Some time later, Armin is seen helping Jean and Sasha carry food into their new relocated house. Jean tries to get Sasha to carry a box while she complains about it's weight. Jean explains that it's filled with potatoes, hinting at her earlier incident with Keith Shadis. Sasha merely brushes it off saying she forgot all about it. Jean disagrees, saying that nobody could forget that incident. Armin mentions that there is inflation all over, and if they lost their current provisions then they would surely starve. After the food is inside, Sasha asks why they bought so much food when they could just easily hunt for it in the woods. Armin reminds her that hunting is prohibited in the area and that if discovered, then there hiding here would be meaningless.
Eren appears and reminds them all of the importance of cleaning off their shoes before coming in. Jean yells at him that he is not his Mother. Mikasa and Historia come back after chopping wood, much to Armin's shock, as he tries to remind her that she is not a wild animal and shouldn't be moving around yet. Eren comments on how he also tried to stop her but she wouldn't listen, and was doing sit-ups. Jean then yells at Eren for daring to spy on Mikasa. Sasha speaks on how this is like all of them being trainees again. Armin is quick to remind everyone that protecting Eren and Historia is an important task. He then asks why they were selected for Levi's new squad, commenting on the fact that many veterans are still alive. Eren tells them all to finish cleaning before Levi and Connie return. 
The group then reunites with Levi and discuss Armin's idea of sealing the hole in Wall Maria using Eren's Titan hardening abilities. Hange informs them that Pastor Nick was found dead that morning, tortured and murdered by members of the Military Police Brigades First Interior Squad, and Armin wonders how much he would have revealed, though Levi guesses he didn't reveal anything. He also was there when Historia told about her past, her mother's murder and the events that led to her enlistment in the Survey Corps. 
During a failed test for Eren to harden his titan form, Armin was present. He was also present when the group read Erwin's orders, looking shocked at the sight of it. During their first official operation, Armin serves as a body double for Historia, and is eventually captured by the organization that wishes to take possession of Eren and Historia. While being held captive with Jean, who was serving as Eren's double, one of the men harassed him, asking over and over to hear Armin's voice, as he was suspected to be Historia. Armin displayed great discomfort at this, being driven to tears from it. 
Armin is seen still tied up with Jean as the men issued to take Eren and Christa arrive, observing them silently before they are attacked by Mikasa and Levi. He and Jean then race from their positions, revealing that they were pretending to be tied up, and tie the beaten men up.After the men are officially detained and questioned by Levi and Mikasa, Levi orders Armin to fix the mouth gag on the man who originally harassed Armin. As he began to fix the gag, the man mentioned that he heard Armin was actually a boy. He then tells Armin that he used to be normal, but Armin now turned him into this and then tells him to do something about it. Armin appears shocked, unresponsive to the man. Jean then tells Armin to leave the work to him.After the Survey Corps capture two central military police officers, Armin is seen with the rest of his friends talking about how they might be able to pull off a successful coup d'etat. He's present when the Survey Corps discuss the plan to make Historia ascend as queen. After Eren and Historia are kidnapped by the central military police, he's seen at Trost district, preparing with the rest of the Survey Corps to retrieve the caskets in which Eren and Historia are being transported. It turns out to be a trap to lure the Survey Corps, and they immediately try to escape town, with Armin driving a carriage. One female member of the central MP gets through and tries to shoot Armin, but Mikasa kicks her and she lands on the carriage. She gets up, ignores Jean's threat and knocks his gun away. While she's pointing a gun at Jean, Armin reacts quickly, pulls out his own gun and shoots her in the head. Thus, he helps save Jean. After the SC retreat to safety, he wasn't able to take the guilt of killing another human being and becomes sick. Mikasa comforts him. Levi tells him that he cannot go back to being the way he was, as his hands are now already dirty.
After the successful revolution, he tags along with his group to the Reiss Chapel, wondering that if Titan shifting abilities can be ingested, who could Eren have eaten to gain his Titan Shifting abilities. He plays a pivotal role in planning out their fight with the remaining Central MP forces stationed at the chapel. The plan was to take cover under the smoke by igniting gunpowder inside barrels and also by utilizing their smoke signals, as it would be advantageous for them with their lower numbers. As Hange gets injured, he is tasked to take care of them.
He witnesses Rod's Titan form crawling out from the collapsing chapel and speculates that it is behaving more like a Deviant Type Titan rather than a human shifter. He assists the Survey Corps in fighting the Titan as it tries to invade Orvud District.Underground.  He and the rest of Survey Corps prepare for the upcoming mission for retaking Wall Maria and have meals together. Before they set out for the mission, he reminisces their childhood with Eren and Mikasa,and enthusiastically talks of being able to see the outside world, stating that they should start by visiting the ocean. 
During the night they walk towards Shiganshina, he prompts Eren as he seems to be in fear and doubt. He implicitly reminds him of their collective dream to see the outside world, making him feel better. 
Once they reach Shiganshina, he scouts around and finds the remains of a camp-fire with 3 cups and a pot that had gone cold. He, along with Erwin, reason that there were at least three enemies around and they were informed of their arrival well in advance.
After this, Erwin entrusts him to command a group of soldiers to weed out the enemies in hiding. He speculates about the enemy's thought process and requests the soldiers to search around inside the walls to find hollow spots. Sure enough, one soldier stumbles across a hollow spot and from within emerges Reiner who immediately kills him. He prepares to attack Armin, but Levi swoops down and intervenes. 
As they blow Reiner's head off, he's sad that with their abilities they couldn't afford any negotiations. However, Reiner gives out a roar and Armin immediately realizes that it might be a signal to call Bertholdt. Sure enough, a barrel is approaching them from the sky. 
Being physically weak, Armin is rarely assigned to the front lines and is rarely seen using his 3DMG for direct combat. Instead, his greatest strength lies in his intelligence - innate abilities of deduction and strategy formulation, be it in a war room or on the fly. But Armin has a keen eye for detail, making him a remarkable field tactician, a trait that distinguishes him amongst his fellow trainees. His strategies helped save his fellow soldiers numerous times and, more remarkably, he played a key role in deducing the identities of all hostile Titan Shifters among the 104th Trainees. Initially, Armin's intelligence was hampered by a severe lack of confidence, but after acknowledging and nurturing this side of himself, Armin's potential as a tactician began to show, and even high-ranking officers take his strategic opinions seriously.
Armin Arlert's Statistics :
- Eren Yeager - Eren is Armin's best friend from childhood. As children, Armin looked up to Eren, as he was always there to protect Armin from bullies regardless of the odds. It was Armin who enthused Eren about the outside world, and together the two would dream of venturing beyond the walls. Initially, Armin felt inferior to Eren, ashamed of being in need of his protection, and lacking the courage his friend boasted. Despite this, it was Eren who would give Armin the confidence to begin using his strategic mind to its full potential, reminding him of the many times his reasoning and quick thinking have saved them. As soldiers, the two share the most powerful bond and, using their own unique abilities, have saved each other numerous times.
- Mikasa Ackerman - Mikasa is a close friend of Armin's. Whenever Armin got into trouble with local bullies, Mikasa would come and save him. Armin looked up to Mikasa's strength and courage and felt inferior to her. Mikasa, however, believed in Armin's abilities to reason out the best solution in a dire situation and trusted him deeply. She was responsible for boosting Armin's confidence and shaping his character.
- Jean Kirstein - While Armin was initially not that close to Jean due to the latter's rivalry with Eren, their relationship has changed considerably since joining the Survey Corps. Armin's growth as a strategist has aligned with Jean's growth as a leader, and the two often share insights or opinions with one another.
- Annie Leonhart - The two are shown to share a mutual respect for each other, expressing admiration for each others' hidden qualities. This causes her to hesitate when attacking in her Titan form, a mistake which allows Armin to discover her true identity. He then uses emotional blackmail in order to lure her into a trap and facilitates her eventual capture.
- Reiner Braun - Reiner is shown to have been protective of Armin, helping him during physical training exercises and carrying him to safety during dangerous operations. Armin initially defends him when he is suspected of being a spy, but quickly realizes the truth and provides evidence of Reiner's guilt.
- Marco Bott - Armin notes that they were friends, and did maintenance of their gear together. This later allows him to recognize Marco's stolen gear when it is presented by Annie as her own.
- The voice of Armin and the narrator of the anime are shared by the same voice actors in Japanese & English, Marina Inoue (in Japanese) and Josh Grelle (in English).
- In the manga, Armin has stated that it is his grandfather, not his parents, who gave him his name.
- The name "Armin" may have multiple meanings, either from an old German word meaning "whole", or "Herman", meaning "soldier".
- His birthday, November 3rd, is celebrated in Japan as Culture Day. This holiday promotes academics, culture, and the fine arts.
- In the side art for Volume 11, Armin, along with a few other characters, was depicted transforming into a Titan. His form had a large head that was almost the same size as his small body. This was also included in the second OVA.
- Hajime Isayama joked in the November 2014 issue of Bessatsu Shōnen Magazine that the girl Mikasa got along with most was Armin. After much confusion, he later corrected himself and stated that Armin is in fact male.
- Isayama has stated that Armin and Nifa are likely aware of their resemblance in looks with each other because it is often mentioned by others.