Eren Yeager

"If someone tries to take my freedom away...I won't hesitate to take theirs. Our father didn't make me that way. I have been like this since birth."

- Eren to Zeke Yeager

Eren Yeager (エレン・イェーガー) is a former member of the Survey Corps. He is the main protagonist of Attack on Titan. He lived in Shiganshina District with his parents until the fall of Wall Maria, where he impotently witnessed his mother being eaten by a Titan. This event would lead to Eren's intense hatred towards the Titans as he swore to wipe all of them off the face of the Earth.

Soon afterward, his father, Grisha Yeager, found him and gave him the key to his basement, instructing Eren to find it at all costs and retake Wall Maria. He then injected Eren with a Titan serum.

In the year 847, Eren, Mikasa Ackerman, and Armin Arlert joined the 104th Training Corps. The three graduated with Eren ranking 5th best, and they joined the Survey Corps following the battle of Trost District.

After finding the basement and unlocking his father's memories, Eren learned about the truth of what the Titans are, as well as the history of Eldia and Marley. Eren then vowed to free his home from their true enemy: the rest of humanity that lives across the ocean.

Eren currently possesses the power of three Titans. From his father, Eren inherited the Attack and Founding Titans. After eating the younger sister of Willy Tybur during the Raid on Liberio, he gained the War Hammer Titan as well.

Human form
Eren is a young man of average height and muscular build. His facial features strongly resemble his mother's; he has a reasonably long, rounded face and sizable, expressive, gray eyes. His hair is short and black, and his bangs fall in a natural, middle-parted, curtain-type style. After his training and during his time as a soldier, he became very physically fit and muscular, although this is often unseen due to his relatively baggy clothing. After the four-year time skip, Eren grew his hair down to his neck.

Eren is first seen wearing typical townsfolk attire that consists of brown trousers, a green shirt with string tassels at the collar, a reddish-brown coat, and simple brown shoes. A few years before the fall of Wall Maria, he also wore a black scarf, which he gave to Mikasa Ackerman the day they met. As a teenager, he is often seen in the typical Survey Corps uniform while training. His casual attire consists of a long beige shirt identical to the one he wore in his first appearance, a maroon sash around his waist, white trousers, and brown knee-high boots. He always keeps the key given to him by his father dangling around his neck on a string.

By the time Eren infiltrates Marley in the year 854, Eren has grown visibly taller, and his hair has grown down to shoulder length. He has a slight mustache and goatee, as well as bandages that cover his forehead and left eye. To maintain his cover, he wears the Eldian armband around his left arm, though he had initially worn the armband around his right arm before it got corrected by Falco Grice. After returning to Paradis Island, Eren discards his Survey Corps attire and begins wearing a white shirt with dark pants underneath a simple black mantle. He ties his hair back into a bun and shaves off his mustache and goatee.

Attack Titan form
Eren's appearance changes quite drastically when he transforms into the Attack Titan. His height increases to, his hair grows long enough to graze his shoulders, and his tongue and ears become elongated. His facial features also undergo a transformation; he develops a prominent, hooked nose, his eyes become deeply sunken within their sockets, and his mouth takes on an unusual, jagged shape that is unsuited for intelligible speech. Despite this, he is capable of howling and roaring in order to express his exhaustion and anger. In addition, he also lacks lips and flesh on his cheeks, so his teeth are exposed.

Similarly to past Attack Titan holders, Eren's Titan form is well-proportioned and physically fit, sporting a well-defined, lean, and muscular appearance in lieu of the more common pot-bellied or emaciated appearances of regular Titans.

Founding Titan form
Eren's Founding Titan is drastically different than Ymir Fritz's Founding Titan, or any other Titan for that matter. Initially, much of the Titan is shrouded by the steam from the Wall Titans, but its sheer size is immediately noted, towering over the horde of Wall Titans. What appears to be the torso is devoid of flesh, resembling an enormous ribcage. The knobs of the backbone and ribs are grossly lengthened; the ribs reaching the ground while the arch of the spine extends far into the sky. The pelvis and legs are greatly undersized however, seemingly useless. Despite this, they are still taller than any Wall Titan.

The upper body seems proportional with the legs, meaning that they are dwarfed by the "ribcage" (although it is revealed that the "ribcage" arose from the lower back). The head is the only part of the body with much flesh, although it is significantly deformed: both the ears and hair are greatly elongated; the cheeks are missing, exposing the molars; and the bottom jaw is nearly bare, only the lips and chin being present. Like a puppet, the upper body is suspended by sinew, supported by the vertebral knobs like a suspension bridge. Inside the Titan, Eren's head is disconnected from his torso; having been decapitated and rejoined by Ymir's power, it is connected by additional vertebrae to what presumably is his body. Some sinew supports his scalp.

The Titan walks with its "ribcage", undulating the ribs like a millipede's legs. It is fast enough to keep within view of the Rumbling.

Pure Titan form
Eren's Pure Titan form was much shorter than his current Titan form. It was tall with short, rugged hair and a jagged, lipless mouth that exposed his teeth. His Pure Titan form also had a big head, elongated ears, and an overall stocky build.

Personality
Eren is best described as hardheaded, strong-willed, passionate, and impulsive, which are attributes of both his strong determination to protect mankind and, eventually, his equally strong determination to escape the Walls. Even as a young child, he was so intent on joining the Survey Corps that he argued with and shouted at his mother, referring to the people in the village as "silly" and comparing them to complacent livestock.

Eren cares deeply for his friends and family, risking harm and even death in order to protect them. As a child, he took on larger boys who bullied Armin Arlert and, more tragically, he attempted to lift the rubble that crushed his mother during the Titans' assault in Shiganshina. Eren is also capable of displaying violent behavior in defense of people he does not even know. This was highlighted when he attempted to rescue Mikasa Ackerman by brutally slaughtering two of the human traffickers who had captured her.

After Armin showed Eren a book depicting the wonders of the outside world, he grew to share his friend's curiosity of the world beyond the Walls and decided to see it for himself. This led Eren to develop a scornful attitude towards anyone who was content to live and die within the Walls' confines without ever setting foot outside. As a result of this, he greatly admired the soldiers of the Survey Corps, regarding them as "heroes" and wishing to join their ranks as soon as he became eligible for enrollment. He was quick to take offense when anyone spoke badly of the Corps, and his determination to join them caused friction between himself, his mother, and to a lesser extent, Mikasa.

Eren has a marked lack of self-restraint that often leads him into trouble, causing his friends and family to worry about him. His limited self-control is evident in his temper, which often caused him to act recklessly in anger, or say things he himself knew he should not have. This is exacerbated by his tendency to view the world in terms of black and white, where individuals who deny others their freedom are worthless scum, unfit to be left alive. Though he has great compassion, Eren has little in the way of empathy and is prone to taking things at face value, evaluating situations or ideas solely by his own arbitrary perspective and rarely ever thinking deeper about them unless someone else points things out for him.

Though Eren spoke about eradicating the Titans with seemingly great confidence, his bravado hid deep insecurities. He was often ready to blame himself and his incompetence whenever something went wrong, believing a course of action he took - or failed to take - was the reason for the disastrous results. This is most evident when he blames himself for the death of the Special Operations Squad at the hands of the Female Titan, and for the deaths of the many veterans that perished in the rescue operation after he had been kidnapped by Reiner Braun and Bertolt Hoover.

Eren's ordeals since the coup d'état have mellowed his personality considerably. When he discovered the truth about where his father had been the night Wall Maria fell, he was willing to ask Historia Reiss to eat him for the good of humanity. He admitted that he viewed himself as weak, and that his reliance on the Attack Titan proved it. It took a lot of encouragement from his friends for him to overcome this state of despair and regain his passion.

By the time he finds out from his father's books that Titans are actually humans who were forced to transform by the Marleyan Government, he seems to have let go of his hatred against them. When passing by a slow-moving Titan en route to the ocean, he shows no signs of anger or unrest, and instead calmly calls the Titan an "Eldian."

Eren possesses great amounts of perseverance, fortitude, and determination. As such, he managed to master the basics of vertical maneuvering equipment, even when his equipment was damaged, and graduate as fifth top student in his class despite his lack of natural talent.

Eren has been noted to be quite charismatic and has a talent for delivering impassioned speeches, often unwittingly managing to persuade the mass of his listeners to sympathize with his point of view. Even Jean Kirstein, his bitter rival, has admitted this, as he convinced over half a dozen recruits to consider joining the Survey Corps before the Battle of Trost. Four years later, he makes use of this skill consciously, as shown when he easily lifts Falco's spirits and convinces him to deliver a letter outside of Liberio, despite the fact that Eldians are usually forbidden from leaving the internment zone.

In the years since the recovery of Shiganshina, Eren has shown remarkable progress in his analytical and tactical skills, both in and outside of battle. Apart from maintaining his cover as a Marleyan soldier for an extended period of time and procuring a method of transporting his letters to the Survey Corps, Eren accurately guesses the source of Falco Grice's injuries and the reason why he wanted to become the next Armored Titan. Later on, he successfully leads Reiner into a trap, and in his battle against the younger sister of Willy, he quickly deduces the true location of the War Hammer Titan. When he is unable to crack the crystal encasing her with his Attack Titan's jaws, he is resourceful enough to use the Jaw Titan's jaws as an improvised nutcracker to kill her and obtain the War Hammer Titan.

Eren is aided in this by his unnervingly stoic and calm demeanor he developed since infiltrating Marley, never losing his composure and usually wearing a blank expression on his face, no matter how dire or stressful the situation may be. Although he admits to becoming angry when Koslow traumatized Eldian soldiers, he remains outwardly unfazed during the incident. Additionally, he appears to have become less proud overall, thanking Mikasa for helping him, which he normally used to dislike and criticize her for.

His infiltration of Marley has given him a change in perspective regarding his enemies. After spending time as a Marleyan soldier, he comes to understand that his enemies are people no different from his own. Because of this, he deeply empathizes with Reiner and the other Warriors who were sent to Paradis Island, letting go of his desire to kill them in revenge for attacking his home and stating that they are simply victims. Nevertheless, he still prioritizes his personal mission of destroying Paradis' enemies for the sake of his people's freedom, regardless of how many lives are lost on either side. Furthermore, this personal mission has driven him enough that he unleashes all of the Wall Titans and declares he will trample the entire world to exterminate all life outside of the island.

Eren believes that righteous goals sometimes require unethical means. He is ready and willing to use such methods himself when he declares war against Marley. Eren abuses the twelve-year-old Falco's trust, fully aware of his family's precarious situation, and eventually kills dozens of innocent Eldian civilians (including children) as collateral damage in a surprise attack on Willy Tybur.

In spite of this, he seems to have developed a dislike for war, referring to it as "hell." He believes that, with good reason, no one would want to go to war if they knew the suffering it would put them through.

Eren's time-serving in the Marley Mid-East War also seems to have had an effect on his psyche to some extent. While he has shown great sorrow for comrades who have died on expeditions, and has demonstrated a great amount of compassion for his fellow graduates from the 104th, he laughs upon hearing that Sasha Blouse's final words were "meat;" although he changes his reaction and is seen about to cry after Jean Kirstein accuses him of being responsible for her death and remembers Sasha's conviction that they would have more sheep and cows after recovering Wall Maria.

It is later revealed that Eren knew the future via the Attack Titan's ability and has been spiraling down a state of depression, knowing what the inevitable outcome of the present will be. While he does wish for a peaceful solution, he understands the impossibility of it better than all around him, even Armin.

History
Eren was born in Shiganshina District on March 30th, 835, in the southern region of Wall Maria to Carla Yeager and Grisha Yeager. He had a few friends, although his best friend was Armin Arlert, whom he often defended from the neighborhood bullies. Armin inspired his passion to leave the Walls and travel by showing him a hidden book about the outside world. He dreamed of joining the Survey Corps as soon as he reached the enlistment age, in order to see the outside world. Because of this dream, Eren and Armin were frequently regarded as heretics and harassed constantly by other children.

When Eren was nine years old he accompanied his father on a house call to the Ackerman family's house only to find both parents murdered and their daughter Mikasa missing. Fearing the worst, Dr. Yeager instructed Eren to stay within the house while he fetched the Military Police. Eren, however, tracked the robbers to a small cabin in the forest behind the house.

Thinking quickly, Eren feigned distress and claimed that he was lost. As one of the robbers approached Eren, he pulled out a hidden knife and stabbed the man. As the second man went after him with an axe, Eren charged him with a makeshift spear, piercing him in the shoulder. Once he was down, Eren proceeded to stab him to death in a wild frenzy while Mikasa looked on.

As Eren untied her in the aftermath, he was caught off-guard by a third robber, who proceeded to strangle him. Eren urged Mikasa, who was frozen in fear, to fight back, warning her that they would both be killed if she did nothing. As Eren began to lose consciousness, Mikasa finally lost all inhibition and lunged at their attacker, stabbing him through the heart and killing him.

When Dr. Yeager eventually returned with the MPs, he took Eren aside, scolding him angrily for his reckless behavior. While Eren was genuinely sorry for upsetting his father, he expressed no remorse whatsoever for killing the robbers. When Mikasa remarked that she was cold, Eren gave her the scarf from his own neck; and when Dr. Yeager invited Mikasa to live with their family from then on, Eren accepted her with no hesitation, tugging on her sleeve and shyly insisting that they return home.

Fall of Shiganshina arc
After Eren is woken from a nightmare by Mikasa, the two walk home through Shiganshina. They are harassed by Hannes, who begins teasing Eren for having apparently cried in his sleep. Eren is annoyed to see that Hannes and his friends are slacking off on the job and refuses to be placated by their claims that the Titans will never breach Wall Maria. Leaving Hannes behind, the children stop again to watch the Survey Corps return from an expedition and Eren is crestfallen to see that the Corps has returned defeated.

Upon returning home, Mikasa reveals to Eren's mother that he wants to join the Survey Corps. Carla forbids him from joining due to the Corps' high mortality rate and begs Grisha to talk some sense into his son. Grisha ignores her objections and instead announces that he will be leaving for a few days on a trip, promising Eren that when he gets back he will show the boy what he has hidden in the basement of their home. Enthralled, Eren joins his mother and Mikasa in waving him off. Carla reminds him that she will not allow him to join the Survey Corps, and they exchange a heated argument before he runs off.

Eren and Mikasa scare off bullies harassing Armin and the three stroll through Shiganshina and settle by the riverbank. Armin deduces that Eren's parents found out he wants to join the Survey Corps before criticizing the widespread belief that it is impossible for the Titans to breach the Walls. Suddenly lightning strikes, and an earthquake breaks out. The three gather in the center of the district with other civilians, where they all gawk in horror at the sight of a Titan larger than Wall Maria. The Titan kicks a hole through Wall Maria's gate, sending massive pieces of debris throughout the town.

Eren and Mikasa hurry home as Titans begin entering the district, arriving to find their house crushed by a large rock and his mother trapped beneath the rubble. As Eren tries to help her, a Titan begins approaching the collapsed house. Hannes arrives, intending to fight off the Titan, but is overcome by fear. Rather than fight the Titan, he takes Eren and Mikasa to safety and abandons Carla.

Hannes leaves Eren and Mikasa on a boat leaving the Titan-infested city. There, Eren and Mikasa witness an Armored Titan destroying the back gate of Shiganshina. As Eren realizes that he can never return home, he vows to kill every Titan in existence.

Eren, along with Mikasa and Armin, are sent to a shelter for refugees from Wall Maria. Soon after, Grisha arrives and finds Eren, who tells him that his mother was eaten. After hearing this, Grisha takes Eren into a nearby forest and instructs him to go to the basement; before Eren can react, Grisha injects him with a Titan serum, turning Eren into a mindless Titan. Eren instinctively eats his father, receiving his Titan powers, including the dormant Founding Titan.

104th Training Corps arc
After the fall of Wall Maria, Eren, Mikasa, and Armin briefly worked on a farm with other survivors of Wall Maria before reaching the proper age to enroll in the Military two years later. During the 104th's rite of passage conducted by instructor Keith Shadis, Eren is ignored alongside others who have clearly experienced trauma in their past.

Before training, Eren draws a crowd of trainees at dinnertime, describing the appearance of the Colossus and Armored Titans. He becomes sick as he remembers his mother being eaten, but when questioned he attributes it to eagerness to begin his training and kill all the Titans with the Survey Corps. Jean Kirstein interrupts Eren and mocks his decision. Eren does not admire Jean's desire to join the Military Police simply to live in the Interior Walls and the two prepare to fight each other. The bell signaling the end of dinner rings breaking the tension and the two drop their disagreement with each other.

The next day, the trainees begin practicing with vertical maneuvering equipment. Eren utterly fails to keep himself steady and takes extra tutoring from Armin and Mikasa. He knocks himself out and at dinner, other trainees mock his performance especially after his pledge to kill all Titans.

Back at the dorm, Connie and Jean do not offer any suggestions and Eren visits Reiner Braun and Bertolt Hoover for help. Although they are reluctant at first, the group bonds over their similar experiences during the fall of Wall Maria. The three exchange tips and depart as friends.

Instructor Shadis gives Eren one last chance to pass his maneuvering equipment test before he will be shipped to the landfills. At first, it appears Eren can maintain his balance but Eren quickly loses control and falls over. Shadis has Eren switch equipment with Thomas Wagner and Eren finds that he is able to easily balance himself and Shadis reveals that the equipment he had been training with was defective.

During hand-to-hand combat training, Eren admits to Reiner that he finds it unnecessary, claiming that it would be much wiser to run away when attacked by another human than to engage them. Reiner reprimands him for his attitude and points Eren to Annie, who is also slacking off. Egged on by Reiner, Eren tries to attack Annie with his mock knife to punish her for slacking off and is quickly disarmed by her unconventional fighting style. She makes short work of Reiner and Eren, enthralled by Annie's proficiency, asks to know who trained her. He is taken aback when she begins to lecture him on the military's flaws, pointing out that it awards its most talented trainees with positions far away from the Titans, where their skills would be most useful.

Annie's words continue to bother Eren, who becomes annoyed at the idea of trainees trying to improve their skills just to stay away from the Titans. Eren confronts Jean for possessing such a mentality, which leads to a physical altercation between the two. Eren easily ends the fight by replicating Annie's moves and proceeds to lecture Jean for slacking off during his training.

At one point during training, Eren takes a bad spill while using his vertical maneuvering equipment. Frustrated, Eren asks Reiner for advice at improving and Reiner tells Eren that the only thing to do is to just keep moving forward.

In 850, Eren graduates in the top 10 of the 104th Training Corps. After graduation, he is assigned to clean the cannons atop Wall Rose with Sasha, Connie, and a few others. There they witness the return of the Colossus Titan, who has not been seen in the last five years. Eren faces the Titan alone in combat as his fellow trainees can all but look on in horror.

Battle of Trost District arc
While his fellow trainees are paralyzed in fear at the sight of the Colossus Titan, Eren attempts to kill it. Despite getting close enough to the Titan to nearly slice the nape of its neck, it vanishes into thin air. Reinforcements arrive and Eren's team is ordered to return to the military's headquarters for orders.

After resupplying at the headquarters, Eren and Armin are assigned to a squad together as part of Trost's middle guard. Mikasa is unhappy to be assigned to a different squad, but she assents when Eren berates her for not obeying orders.

Despite their nerves, Eren's squad enters the battle in high spirits, viewing the upcoming battle as an opportunity to prove their mettle as soldiers before they enter the Survey Corps. However, things immediately take a turn for the worst when Thomas Wagner is devoured. Enraged, Eren tries to kill the Titan, only to be incapacitated by a second Titan biting off his leg. Eren regains consciousness just in time to save Armin from being eaten, being swallowed himself in the process.

In the stomach of the Titan, Eren comes across the dead or dying soldiers who were devoured by the Titan. As he remembers his goal to kill every last Titan alive, his anguish triggers his first transformation into his Attack Titan form. Bursting out of the Titan that devoured him, he proceeds to wreak havoc on all the Titans he finds. In the process, he unknowingly saves Mikasa’s life from another Titan and is baited by Armin, Connie, and Mikasa to help fend off a procession of Titans from a storage headquarters for the compressed gas used to power their maneuvering gear.

Eventually, Eren appears to run out of energy and begins to be overwhelmed by the Titans. The sight of the Titan that killed Thomas proves to be enough to drive Eren to throw off the Titans holding him down and kill the Titan by biting its nape off. As soon as the massacre is over, Eren falls to the ground and his human form emerges from the back of his Titan form’s neck, to the shock of all the onlookers. He is retrieved by an overwhelmed Mikasa.

When he regains consciousness, Eren finds himself cornered with Armin and Mikasa by a hostile military force which has decided to execute him as a possible threat due to his powers. Due to his hazy memories of what happened during the battle Eren is unable to answer their questions satisfactorily and they fire a cannon at him and his friends. Eren instinctively grabs onto his two friends and bites his own hand, partially transforming into a Titan and blocking the cannonball with the Titan's hand. While the cannon is being reloaded, Eren reveals to Mikasa and Armin that he intends to use his power to go over the wall and try to reach his father's basement on his own. Mikasa and Armin both protest the decision and Eren tells them that he will stay behind if Armin can convince the amassed soldiers not to kill him.

Armin's plea falls on deaf ears among the soldiers who have cornered them, but the trio is saved by the arrival of Commander Dot Pixis, who intervenes on their behalf. Pixis takes the three to the top of Wall Rose and questions Eren personally. Eren's answers satisfy Pixis and the man calls his subordinates to help devise a plan to retake Trost with Eren's powers. A plan is made for Eren to use his Titan form to reseal Trost's gate with a boulder that is in the middle of the district.

Upon his transformation to execute the plan, Eren loses control and attacks Mikasa before inadvertently rendering himself unconscious. When his body fails to regenerate, the mission is declared a failure. Armin arrives on the scene and convinces Mikasa to go help fend off the Titans while he tries to get through to Eren. Armin manages to rouse Eren slightly by stabbing into his Titan's nape and piercing his human body. Armin manages to bring Eren back by reminding him of their desire to see the world together, causing Eren to remember how he wanted to join the Survey Corps and destroy all the Titans. Eren moves the stone and is able to plug the hole in the Wall at the sacrifice of the rest of the team members, with the exception of Rico, Armin, and Mikasa. They are saved from the desperate situation after Eren’s transformation back to human by Levi Ackerman.

After the events of Trost, Eren is placed in the custody of the Military Police and kept chained in a dungeon prison cell in the Royal Capital beneath a courtroom. While he is there, he is paid a visit by Commander Erwin Smith and Levi. Upon hearing his motive to kill Titans, Levi says he will accept him into the Survey Corps. Eren is left there for some time before being escorted by Corps members to the courtroom where he was tried, with Darius Zackly preceding over events.

During his trial, the Military Police and Church of the Walls call for his dissection and execution while the Survey Corps, argues in favor of using his power to their advantage in scouting missions. After an outburst by Eren, Levi savagely beats him to prove that Eren will not pose a threat to him. It is decided his fate will be decided after a “test” mission with the Survey Corps. Afterward, Erwin thanks him for his cooperation.

The Female Titan arc
After joining the Survey Corps, Eren is assigned to Levi's Special Operations Squad and sent to an abandoned castle which had formerly served as the base of operations for the Survey Corps. While there, he is tasked with cleaning duty by Levi while also helping Squad Leader Hange Zoë with their Titan experiments.

During one of the experiments with his Titan abilities, Eren is lowered into a well before being told to transform into a Titan, in case he loses control. However, Eren is unable to activate his Titan abilities. He is eventually brought back to the surface and has his wounds tended to by Levi's squad. Later, whilst bending over to pick up a dropped spoon with his injured hand, Eren accidentally triggers his Titan ability in a partial transformation, creating a Titan hand in a small explosion.

Levi's squad surrounds Eren, demanding that he prove he is not a threat to them, and the situation has to be defused by Levi and Hange. After the incident, with the help of Hange's deductions, Eren learns that a Titan transformation requires him to have a clear goal in mind in addition to self-injury.

Eren meets some of his classmates from the 104th Training Corps who have opted to join the Survey Corps. He learns of Marco's death from Jean, who lectures him about his responsibilities to humanity.

After a month of training, Eren and the Survey Corps embark on the 57th Expedition Outside the Walls. During the expedition, Eren is positioned at the center of the Long-Distance Enemy Scouting Formation, where it is the safest. However, per Erwin's orders, the knowledge of Eren's location within the formation is given only to a select few while the rest of the soldiers are given false information in order to misdirect any spies within their midst.

It soon becomes apparent that something is going wrong with the expedition. Squad Levi receives the news of the decimation of the right wing of the formation and see black flares signaling the presence of an Abnormal in close proximity, even though their position should be safest. Soon after, the soldiers head toward a Titan Forest. The central column of the scouting force, including Eren and Levi's squad, are told to enter the forest while the rest of the soldiers stand guard at the perimeter of the forest to prevent any Titans from entering.

After entering the forest Squad Levi is set upon by a seemingly intelligent Female Titan, who is able to dispatch pursuing soldiers with ease. Seeing the soldiers perish one by one, Eren is tempted to use his Titan power to save them. Levi gives him permission, but Eren decides to trust in his team after recalling the trust they have had in him.

As the Titan approaches the squad, it is caught in an ambush set up by Erwin. Eren and the rest of his team excluding Levi ride out of the forest firm in the belief that the Titan was captured and her human self apprehended. The squad stands by and discuss Erwin's decision not to tell the soldiers about the plan while Levi consults with the commander. Eren wonders why is it that not even the elite soldiers were told about it, angering Oluo and Petra. Eld agrees with Eren, stating that Erwin must have had a reason. Remembering the odd question Erwin asked them when Sonny and Bean were killed, they realize that if they had answered correctly they would probably be trusted enough to be let in on the operation.

Seeing a flare that indicates the Corps is retreating, the squad begins making their way out of the forest. They notice another signal flare fired in response, believing it to be Levi's. However, the mysterious soldier kills Gunther and then transforms into the Female Titan to resume her pursuit of Eren. The remaining three team members tell Eren to go on while they attack the Female Titan. Eren agrees to retreat but regrets his decision when the Titan manages to overpower and kill them. Filled with regret, Eren transforms and engages the Female Titan.

Even though he initially had the upper hand against the crippled Female Titan, Eren quickly expends all of his energy and ultimately loses the fight. His human form is eaten by the Female Titan just as Mikasa arrives on the scene. Working with Levi, Mikasa is able to rescue Eren from the Titan. The Survey Corps returns to Wall Rose in defeat. Due to the mission's failure, the military orders that Eren be turned over to the government.

Before Eren can be handed over to the Military, he is let in on a plan by Erwin to capture the Female Titan, whom Armin has deduced to be Annie Leonhart of the 104th. Eren is initially shocked and angry at the accusation, refusing to believe that such a betrayal by one of his fellow trainees is possible. However, he is forced to acknowledge that the fighting style the Female Titan exhibited was exactly the same as Annie's. Reluctantly, he agrees to participate in the plan to capture her.

After Armin convinces Annie to join them in escorting Eren out of Stohess District, they lead her to the entrance to an underground tunnel. Eren begs her to join them and prove her innocence, but Annie refuses. Several soldiers ambush Annie and she transforms, forcing Eren and his friends underground. Eren tries to go into Titan form by injuring himself but cannot due to shock and disbelief at Annie's betrayal, and his friendship with Annie making him unwilling to fight her. As Mikasa and Armin depart to attempt to lead Annie away, Eren is reminded of the lives Annie took as the Female Titan as well as his vow to exterminate the Titans, allowing him to finally overcome his inhibitions and transform into his Titan form.

Even though Eren is in better control of his Titan and is equipped with knowledge of his opponent this time round, he is ultimately no match for Annie's superior fighting technique and hardening ability. He manages to throw Annie into some buildings, but gets his right leg taken off by a hardened kick from Annie, who proceeds to slam him into a building and pummel his head repeatedly with her hardened fist.

Annie attempts to climb Wall Sheena to escape, but has her fingers severed by Mikasa, causing her to fall back to the ground, where she is set upon by Eren, who holds her down as corps soldiers pry open her nape.

Clash of the Titans arc
When Wall Rose is supposedly breached, Eren is among one of the teams within the area to survey the Wall for the supposed breach. While en route to Ehrmich District, Eren is appalled to learn that Minister Nick helped keep the Colossus Titans inside the Walls secret and begs him to tell them anything else he might know. Nick proves to be tight-lipped and Hange instead decides to inform Eren of their plan to try to replicate the Female Titan's hardening ability in Eren so that he can use his own Titan's body to seal Wall Rose.

After learning from Nick that Krista Lenz will be able to divulge more secrets about the Walls, Eren accompanies Hange's squad to Utgard Castle to save the soldiers trapped there. They arrive just in time to save their comrades, excluding the members of Squad Mike who have already died. During the rescue Eren kills his first Titan while in human form but is scolded for breaking cover and endangering himself.

In the aftermath, Eren is among the soldiers on top the Wall recovering from the ordeal at Utgard. He asks about Ymir's condition before going to help an injured Reiner climb the Wall. As he helps Armin up Eren tries to check on Reiner, who begins complaining about his repeated near-death experiences. Hannes arrives with news that there is no hole or breach in the Wall, prompting Eren to question if Hannes is drunk. As Hange orders them to stay on standby in Trost District, Reiner asks to speak with Eren in private.

Leading Eren away, Reiner reveals that he and Bertolt are the Armored and Colossus Titans, explaining that they will need to continue their attacks on the Walls if Eren returns to their hometown with them. Eren recalls Hange inquiring about Reiner and Bertolt potentially being accomplices to Annie, and tries to persuade Reiner that he is tired and simply not thinking straight. In response to Eren's disbelief, Reiner removes the bandage on his arm and reveals that his wounds are regenerating. Mikasa attempts to intervene and protect Eren, but Reiner and Bertolt transform into their Titan forms and attack. Reiner grabs Eren while Bertolt kidnaps Ymir and Eren, disgusted by his former friends, transforms himself.

Eren and Reiner grapple with one another while Hange's squad attempts to take Bertolt down. Eren grows increasingly angry as he remembers all of the pain Reiner and Bertolt inflicted on Paradis, but he is unable to do any damage to Reiner with brute force due to the latter's armor. Instead, he opts to uses Annie's fighting techniques, grappling with Reiner until he locks his foe in a submission hold. As Eren holds Reiner, he focuses pressure on one of Reiner's arms, breaking the armor around the joints and tearing the arm off completely.

With Reiner crippled, Eren falls back to the Wall where Hange orders him to find a way to destroy Reiner's legs so that he can flee without being pursued. Eren is caught off guard by Reiner attacking him head on, but he manages to lock Reiner in another submission hold. As Mikasa slashes Reiner's legs, Eren begins applying pressure to his nape, causing its armor to crack. However, before he can break Reiner out of his Titan Reiner begins roaring, causing Bertolt's Titan to roll off the top of the wall, landing atop both of them.

Eren and Ymir are taken to the Titan Forest by Reiner and Bertolt. He attempts to transform into his Titan form in spite of losing his arms, but Ymir points out that they are surrounded by Titans and have no maneuvering equipment to escape. As they wait to depart at sundown, Ymir and Eren discover that Reiner has developed a split personality due to the guilt of betraying his comrades. Eren is enraged, thinking that Reiner has no right to feel sorry for himself after what he has done. Reiner and Bertolt try to offer Eren and Ymir a chance to join them in order to protect their loved ones but Eren furiously refuses and blames both Reiner and Bertolt for causing the hardship he has had to endure. Eren continues to violently resist his captors, causing Reiner to knock him out. His unconscious form is strapped to Bertolt's back to be carried.

Eren awakes in the midst of an attempt by the Survey Corps to rescue him and immediately begins resisting his captors again. In an attempt to free himself from Pure Titans which have begun to attack him, Reiner is forced to stop using his hands to cover Eren and Bertolt, exposing them and giving Mikasa the opportunity to attack Bertolt. As she rushes forward, Bertolt dodges and Eren tries in vain to warn Mikasa of a Titan behind her.

Armin distracts Bertolt, giving Erwin enough time to cut Eren free from his captors. Mikasa then grabs him before landing on their horses. As they flee, a large Titan is sent flying and creates a large explosion of dust. This causes some soldiers to fall off their horses including Eren and Mikasa. As the two pick themselves up, they are horrified to see the Titan which ate Carla approaching them.

Hannes steps forward to protect Eren and Mikasa. While he distracts the Titan, Eren shouts for Mikasa to free him, believing that he is the only one who can save their lives. But when he tries to transform into a Titan, nothing happens because he is still recovering from his injuries.

He is devastated when Hannes gets eaten, devastated at the thought that nothing has changed from when he was 10 and was powerless to save either his mother or Hannes. Mikasa attempts to reassure him, telling Eren that she wants to thank him for teaching her how to live, and for wrapping his muffler on her which she always wears. Filled with newfound conviction, Eren vows to Mikasa that he will wrap the muffler around her as many times as he needs to. In a desperate attempt, Eren punches the Smiling Titan in the hand as it reaches for him. Eren screams and another Titan attacks the Smiling Titan. Elsewhere around them, the Titans that were fighting the soldiers turn and start running to the Smiling Titan, surrounding and devouring it. Eren takes advantage of the situation and flees, carrying Mikasa on his back. When Reiner and Bertolt pursue him, he screams again and the Titans turn to attack them.

Royal Government arc
Eren and the unified military group manage to return to Wall Rose. Armin notes how Eren seemingly controlled the Titans on the way back, but Eren is not confident in the ability. While Eren tries to remember exactly what happened and how, Jean tells him that whether it was worth paying the price to rescue him will depend on what Eren does going forward. Eren finds it odd to be lectured by Jean, but recognizes that he is right and vows to no longer hesitate.

Approximately one week later, he and the new Squad Levi move into a secluded cabin. Levi begins a meeting with his and Hange's squads, announcing their plan to use Eren's hardening to seal Wall Maria. At Levi's request Hange begins testing Eren's hardening abilities, but little success is had. Eren fails to show any signs of hardening and the longer he tries, the more malformed his Titan body becomes. Eren is discouraged by the results, but Hange and Levi manage to cheer him up by reminding him that they learned a lot about his abilities and limitations.

After receiving word from Erwin, Eren moves out along with the rest of Levi's squad and heads to their rendezvous point in Trost District. However, he does not accompany them inside. Instead, he waits with Historia in an undisclosed location. The two of them bond over dreams they cannot remember and expectations they cannot meet. Historia notes that the others must be disappointed by how empty her true self is compared to her Krista persona, and Eren tells her that he likes her new personality more than her old one.

One morning Eren remembers a new detail from his time with Bertolt, Reiner, and Ymir and takes the information to Hange. Hange departs with the information to take to Erwin and Nifa returns with a message from the night before. Erwin's plan is to have Historia take the throne, since the Reiss family is the true royal family. To lure out Rod Reiss, Eren and Historia are handed over to the Reeves Company to be delivered to the Military Police.

Eren and Historia are tied up in a remote location by Dimo Reeves so they can be handed over to the Military Police's First Interior Squad. Reeves hides tiny blades on Eren so that he will be able to cut himself in case of an emergency. However, the Military Police anticipate a trap and take away the hidden blades before they can be used. Eren and Historia are then loaded into a carriage.

Eren awakes in a large crystalline cavern, gagged and restrained by chains atop a raised platform. As he struggles to break free, he spots Historia approaching below him. He is glad to see she is safe and Historia assures him that her father has been misunderstood, having only acted in ways that are beneficial for humanity. Eren finds the cavern they are in familiar and Rod suggests that he and Historia lay their hands on Eren's back to help him remember. When they do, Eren begins seeing his father Grisha's memories and is stunned to learn that he ate his own father.

Once the three of them are alone, Rod opens a satchel and reveals a syringe, which Eren recognizes as the same kind his father had used on him. Rod explains that the Founding Titan's powers can only be fully utilized by a member of the Reiss family. Kenny, overhearing Rod's words as he returns, is distraught to learn he will not be able to use Frieda's power if he devours Eren. Intending to force Eren and Historia to battle each other over possession of Frieda's power, Kenny cuts open Eren's forehead so that he will be able to transform, before retreating to a safe distance.

However, Eren refuses to transform. Heartbroken to learn that Frieda could have put an end to the Titans and prevented so many of the deaths that had occurred since the fall of Wall Maria, Eren begs Historia to eat him so that she can use the power that his father stole to save humanity. Moved by Eren's words, Historia incapacitates her father and begins freeing Eren from the restraints that still hold him, to Eren's shock and despair.

As Rod transforms himself into a Titan, Eren begs Historia to allow her father to eat him. Historia refuses, explaining that even if she is an enemy to humanity, she is still Eren's friend. She is blown back by the winds created from Rod's transformation, but Levi and his squad arrive in time to save her and get the keys to Eren's chains. The ceiling begins caving in due to the sheer size of Rod's Titan and the squad's escape is blocked. Eren realizes that everyone with him is going to die.

As the squad considers ways to escape, Eren apologizes for being useless and Levi tells him that he has a choice to make. Spurred by Levi's words, Eren grabs a bottle labeled "Armor" that had fallen out of Rod's satchel and bites into it. After transforming into a Titan, Eren is able to harden it and reinforce the structural integrity of the cavern around it.

The squad climbs out of the ruined cavern and regroups to chase after Rod, who has become an Abnormal Titan twice the size of the Colossus Titan. Eren still considers being eaten by Rod to save humanity but Historia argues that the Reiss family has already tried undoing the brainwashing and once Rod has the Founding Titan's power, he can alter everyone's memories so they have no interest in restraining him.

Historia argues that taking away the Reiss family's ability to alter memories was the only way to save humanity, prompting Eren to remember his father's words from right before he injected him. His father asked him to learn to control this power to save Mikasa, Armin, and everyone else. They meet up with Erwin and his forces, and the soldiers all proceed to Orvud District to intercept Rod's Titan.

Eren helps the Survey Corps stack barrels of gunpowder together on a net of rope. He watches Historia stand up to Erwin and admires how strong she has become compared to him. Feeling melancholy that humanity has to depend on someone like him, he spots children in Orvud who remind him of himself as a child and thinks back to when the Colossus Titan appeared. Armin tells him that it will be different from before, because this time the soldiers on the Wall can fight back. Eren punches himself, to try beating out his feelings of uselessness.

When Rod's Titan arrives and pulls itself up to the Wall, Eren transforms into his Titan form. He takes the net stuffed with barrels and shoves it into the open mouth of the Titan, which is hot enough to make the gunpowder ignite. This causes the Titan's head and neck to explode and enables the Survey Corps soldiers to attack the flying chunks of meat in hope of destroying the nape.

Two months after Historia becomes queen, Eren and the other members of the 104th volunteer at an orphanage that she has started. As Eren helps Historia, she asks about the progress of his hardening experiments. Eren says they are going well, but wants to speed up the training before Reiner and Bertolt come back. She asks what he would do if they meet up again, and Eren says he will have to kill them. Eren compliments Historia for the work she has done, prompting Mikasa to abruptly interrupt the conversation and take Eren's load away from him.

Thanks to Eren's hardening experiments, the Executioner from Hell is developed, giving soldiers a reusable weapon to safely kill Titans without risking their lives. However, creating the materials for one puts a strain on Eren's body.

As Eren and his friends eat dinner in the mess hall, Eren recalls the events of the past few months, particularly those concerning Ymir and how she said her life was like a nightmare when she was a Titan outside of the Walls. He wonders if there was a time when he was like that too, but all he remembers is what his father saw when Eren ate him. Jean advises that Eren focus on remembering is the identity of the Survey Corps soldier from his father's memories. Jean jokes that a headbutt from their instructor would bring the memory back and Eren realizes that the man his father had seen was instructor Keith Shadis.

Return to Shiganshina arc
The next morning, Eren and his comrades visit Keith Shadis, their former instructor. Eren asks him to tell them all that he knows and Keith tells him how he met Grisha and everything he knows about him. Keith confesses that he is nothing more than a bystander and that he has no power to change things.

The day before the operation to retake Wall Maria, the soldiers are having a great dinner in order to ready them for the operation. Eren and Connie are forced to restrain Sasha to keep her from eating everything. The two reflect on how much things have changed in three months since the battle of Trost. Jean starts a fight with Eren by insulting him and their fight is eventually stopped by Levi.

After the fight, Eren, Armin and Mikasa have a conversation about their future. They talk about how strong and weak people need to combine their abilities in order to succeed. After mistaking a Garrison with Hannes, Mikasa wonders if they will be able to go back to easier times when they retake Wall Maria. Eren answers that it may not be possible, but that is the reason why they must make them pay.

The next morning, the soldiers are ready to travel. They get very surprised when they see that the civilians are cheering them. Finally, Erwin orders the start of the operation and Eren travels towards Shiganshina along with Squad Levi.

While traveling on foot under the cover of night, Eren apologizes to Mikasa, who is escorting his horse in addition to her own, but she insists that he save his energy so that he can seal Wall Maria. Eren is surprised to find himself shaking in anticipation. He insists that he is just shaking from the cold, but Armin reassures him that it is normal to feel scared of the Titans and reminds Eren of when he was nearly eaten during the Battle for Trost. Eren reveals that he sacrificed himself to save Armin that day because he had remembered the first time Armin told him about the outside world, which had caused him to realize just how much the Titans had taken from the humans.

Arriving in Shiganshina, the Corps soldiers quickly scale Wall Maria with their vertical maneuvering equipment. Soaring over Wall Maria, Eren transforms into his Titan form and uses his hardening abilities to seal its hole. Mikasa retrieves him and carries him back to the top of the Wall.

While going to meet up with the rest of the Corps, Hange orders Eren's squad to take up positions along the top of the Wall after observing a signal flare fired by Erwin. To Eren's shock, Reiner emerges from the inside of the Wall and kill a Corps soldier before being attacked by Levi. As Reiner transforms into his Titan form, Eren is surprised again by the sudden appearance of an army of Titans on the outskirts of Shiganshina, with the Beast Titan leading them.

On Erwin's orders, Eren descends into Shiganshina where he changes into his Titan form and acts as bait to draw Reiner's attention. After leading Reiner away from Wall Maria, Eren begins to engage him, using his new hardening abilities to cover his fists in armor. Although he initially has the upper hand against Reiner, Eren is momentarily overpowered and pinned to the ground. He manages to regain control of the fight and throw Reiner off of him, and into an area where Hange's squad can attack. As Eren watches, Hange's squad blinds Reiner with their Thunder Spears before blowing open his Titan form's nape and apparently killing him.

After being informed that Bertolt is approaching, Hange orders Eren and his comrades to retreat from Reiner's immediate vicinity to avoid the blast from Bertolt's transformation. After Armin fails to negotiate with Bertolt, Bertolt transforms into his Titan form and Eren uses his Titan form to shield his comrades from the blast. Armin gives control of the squad to Jean and Eren begins to retreat from Bertolt's position on Jean's orders, using a nearby building to keep himself hidden.

Eren attempts to draw his attention away from Wall Maria and the Survey Corps' remaining soldiers. Bertolt ignores him and Eren and his comrades are left with no choice but to engage him. As his comrades flank Bertolt, Eren grabs one of Bertolt's legs and attempts to push him back. Bertolt simply kicks Eren into the side of Wall Maria, leaving him incapacitated.

After Armin wakes him up, Eren reluctantly goes along with Armin's plan, pretending to fall down to the ground and become immobile in front of the north gate while Armin pretends to act shocked. Escaping his Titan form after hardening it, Eren then grapples onto the nape of the Colossus Titan, slices it open, and yanks Bertolt out. Once Bertolt is incapacitated, Eren finds Armin's charred body.

Eren laments that he could not prevent Armin from being killed. He notices Zeke closing in on him and threatens to kill Bertolt if Zeke comes any closer. To Eren's shock, Zeke claims that he has been enslaved by his father Grisha's ideology and promises to save him. Before Eren can question him Zeke retreats as Levi arrives. Noticing that Armin is still breathing, Eren begs Levi to use the Titan serum on him. Levi initially agrees before deciding to give it to Erwin upon learning that the commander is still alive. He tries reminding Levi of all that Armin accomplished as reasons that he should be spared. Levi ultimately chooses Armin. As Armin returns to his human form after devouring Bertolt, Eren and the 104th go to reunite with him.

When Armin wakes up, Eren explains what has transpired to him, including Bertolt's death. He, Hange, Levi, and Mikasa make their way to his basement. However, they discover that the key Grisha had given him does not fit the lock. Levi kicks down the door and they enter an office. It seems to be nondescript until Mikasa finds a keyhole in Grisha's desk. Eren tries the key on it and it opens to reveal a drawer that appears to be empty. They find a false bottom in the drawer and underneath it are preserved books. Eren, with Mikasa, opens one of them and finds a picture of a family. On the back of it is a message of Grisha that the picture is called a "photograph" and that humanity has not perished.

Upon returning victorious to the Walls, Eren and Mikasa are placed in detention for disobeying orders from Levi and Hange. While serving his sentence, he helps Armin verify the contents of Grisha's books regarding the outside world and the true nature of the Titans by comparing them with his memories that Grisha passed down to him. During one of his nightmares, he is startled awake with the realization that Dina, Grisha's first wife, was the Smiling Titan who had devoured his mother.

Hange and Levi release Eren and Mikasa from detention ten days early, informing them that their punishment was only to set an example to the public and that their help is needed to chart a new course for the Survey Corps in light of the new revelations about the outside world.

Eren and the survivors attend a meeting with the rest of the military, including the Queen, to discuss the results of the expedition to Shiganshina and the information about the outside world recovered from Grisha's books. During the meeting, Eren realizes that the reason he was able to activate the Founding Titan's powers in the past was because he had physical contact with Dina Fritz, a member of the royal family. Eren chooses to withhold the revelation, reasoning that it is not the proper occasion to discuss such a controversial idea, especially if it involves having Historia turn into a Titan so he can control the Founding Titan.

The surviving members of the Survey Corps later attend a ceremony to be commemorated with medals for their bravery and success in Shiganshina. Before the ceremony begins, Floch Forster confronts Armin about the decision to save him over Erwin, angering Eren. An argument begins but before it can escalate it was broken apart by Jean. Armin, agreeing with Floch's argument, is comforted by Eren who reminds Armin of his dream to see the ocean. The ceremony begins and while receiving his medal from Historia, Eren kisses her hand and begins receiving his father's memories of the night he killed the Reiss family. Along with his father's memories of that night, Eren also receives memories from himself, sent to his father from the year 854 via the Attack Titan, effectively allowing him to see the future. The memories he receives of the plan he will enact to save Eldia leaves Eren visibly distressed.

In roughly a year the Titan Guillotine vanquishes all Titans within Wall Maria, Shiganshina District is repopulated, and the Survey Corps hold their first expedition beyond the Walls in six years. The Survey Corps encounters a deformed Titan, who had been crawling towards the Wall, and Eren identifies the Titan as a former compatriot. The Survey Corps follows the deformed Titan's trail until they reach the edge of Paradis Island.

The Survey Corps go down to the beach front, dismounting their horses and taking off their boots. Armin is overjoyed by the ocean, but Eren solemnly notes that the other side of the ocean does not hold freedom as he used to believe. Enemies exist on the other side of the ocean and Eren wonders if killing everybody across the ocean will bring the people of the Walls freedom.

Marley arc
In the year 851, Eren works with Hange Zoë and the Survey Corps to prepare for Marleyan action against Paradis Island. Eventually, the first scouting ship arrives and Eren uses his Titan form to pick it up and beach it on the shoreline. At a meeting between members of the Eldian Military, Eren supports the plan made by Zeke Yeager and reveals the encounter with Dina Fritz that caused him to activate the powers of the Founding Titan. He explains to Hange and Levi Ackerman that he stayed quiet so that Historia Reiss's life would not be threatened.

Over the next three years, Marley sends a total of 32 scouting ships to Paradis Island, all of which are destroyed by Eren and Armin Arlert. While at a shooting range, Eren asks Armin if he has seen anything from Bertolt Hoover's memories that could help them. Armin ponders if it is possible for Paradis Island and Marley to resolve their misunderstandings diplomatically, but Eren brushes him off. Arguing that everyone still sees them as devils, he reaffirms his position that Paradis must strike the first blow in order to buy the island time.

Eren later attends a meeting between Kiyomi Azumabito, from the nation of Hizuru, and the heads of Paradis on forming an alliance. When Eren hears that one of the three paths of action would involve Historia succeeding Zeke as the Beast Titan, he refuses to accept the plan.

In 853, while helping his friends assemble a train line, Eren is very disappointed to hear that Hizuru has been unable to find additional allies for them. Mentioning that Zeke only has two years left to live before he dies, Eren ponders who should take his Titan when he himself must pass it on. His friends offer themselves but he tells them that he wants them to live long lives.

Roughly a year later Floch allows Yelena to discreetly meet with Eren at least once during a festival in Trost. Yelena explains Zeke's plan to euthanize the Eldian race along with his plan to feed his spinal fluid to the Military's officers so that they will not be able to oppose his or Eren's movements. Yelena would later deny advising him to infiltrate Marley on his own. Eren also learns from Yelena that Zeke wishes to speak with him in regards to his true intentions to free Paradis.

Following his meeting with Yelena, Eren meets with Floch privately and tells him that he wants them to pretend to cooperate with Zeke's plan. Floch asks what he actually wants to do while pretending to cooperate with Zeke and Eren tells Floch his plan to use the Founding Titan to kill everyone outside of Paradis.

Eren meets with Historia and warns her that the Military Police are planning to feed Zeke to her, advising her to either fight or run to avoid becoming one of the Nine Titans. Historia refuses to oppose the MPs, explaining that she is willing to sacrifice herself if it will save Paradis. Eren reveals his plan to destroy the outside world to her, horrifying Historia. She reminds Eren that most of the people outside the Walls have nothing to do with Paradis but Eren insists that the only way to end the aggression towards Paradis is to wipe out anyone not strictly allied with them. Eren offers to erase Historia's memory with the Founding Titan if she cannot live with the guilt of knowing his plan.

Eren is one of several Survey Corpsmen who journey to Marley's mainland to meet with Kiyomi. Although his companions are thrilled by the new experiences beyond the walls, Eren remains stoic, only commenting on things which he recognizes from his father's memories. Eren explores Marley, agonizing over the knowledge that he will soon be responsible for killing everyone. Remembering Karl Fritz's desire for the Eldian people to die out, Eren admits that such an outcome would lead to less deaths and finally rid the world of Titans, but he finds himself unable to accept such a fate. He finds a boy being beaten by merchants for stealing and recognizes from his memories that he is going to save the boy. He attempts to convince himself not to and leave, knowing that he will ultimately kill the boy himself in the rumbling, but he is unable to stop himself from intervening.

Eren returns the boy to his village, sullenly noting that he was unable to change the future. In tears, he apologizes to the boy. The boy returns to his tent just as Mikasa arrives to look for Eren. He brushes off her worried comments about his reckless behavior, instead commenting on the similarities between the boy's family and their experiences when Shiganshina was breached. Eren asks Mikasa why she displays so much concern for him and Mikasa, surprised, claims it is because they are family. They are joined by Jean, Armin, Connie and Sasha and the group is welcomed into the tent by the boy's family, spending the night drinking and carousing.

The soldiers sit in on a hearing between politicians to discuss Eldian mistreatment. When the speaker begins calling for the hatred being shown towards Eldians to be redirected towards the Eldians living on Paradis, Eren quietly leaves the meeting.

Before the end of the Marley Mid-East War, Eren cuts off his own leg and gouges out one of his eyes to infiltrate the Marley military as an injured Eldian soldier. He returns to Liberio and is sent to the hospital along with the other wounded and traumatized Eldian soldiers. After being knocked to the floor by a terrified soldier, he is helped up by Falco Grice who points out that his armband is on the wrong arm.

Using the alias of Kruger, Eren is visited by Falco while he is in the hospital. He admits to Falco that he has been faking amnesia so that he will not be discharged and asks the boy to send a letter for him from outside of the internment zone so that the hospital will not figure out that he is faking his illness. Eren says the letter is to his family, to let them know he is all right.

During his stay in Liberio, Eren meets with Zeke and learns about the true nature behind the Ackerman clan lineage. Eren asks Zeke if Mikasa's headaches are something every Ackerman experiences and Zeke claims to have never heard of such symptoms. Zeke tells Eren that he does not believe that Ackermans truly have ingrained behaviors toward a host, instead suggesting that Mikasa simply likes Eren. Eren replies that he only has 4 years left to live, and wishes for his friends to live longer. Zeke asks if Eren would go through with his plan set to save the Subjects of Ymir by euthanizing them. Eren claims that their father was mistaken and agrees with Zeke's earlier claim that Grisha had brainwashed him into following his plan. Eren laments that there would be no suffering had the Eldians never been born and agrees to work with Zeke.

Eren continues to receive visits from Falco, who delivers more of his letters. During this time, Eren learns that Reiner is still alive and is Falco's superior. After Falco leaves, one of the hospital's doctors sits down next to Eren and introduces himself as Yeager. The two talk about Falco, and Yeager asks Eren to stop using Falco to run errands, so that there would be no risk of undoing the hard work that had returned peace to the Grice family. Eren asks Yeager if he has any regrets about his family, causing the doctor to have a mental breakdown.

Just before the start of the Tybur festival, Eren leaves the hospital and takes up residence in a building near the stage Willy Tybur will be performing a play on. En route, he runs into Falco and asks the boy to bring Reiner to him. Upon Reiner's arrival, he asks Eren why he is in Marley, and Eren responds that he is there for the same reason as Reiner; he has no choice. Revealing that he has already slit his hand in preparation to transform if need be, Eren insists that Reiner sit with him to listen to the play.

Eren regenerates his leg and apologizes to Falco for deceiving him, admitting that the letters Falco sent were not to his family but to his allies stationed in Marley. Overhearing Willy claim that he is a threat to Marley's peace, Eren admits that he is indeed the "bad guy," but argues that the Warriors were also the bad guys when they invaded Wall Maria. Eren asks why Reiner and the others broke the wall and Reiner says that it was so they could capture the Founder and save the world. Reiner asks if Eren has come to kill him and Eren admits that he has seen that there are both good and evil people in Marley. He admits that he understands the turmoil Reiner went through, causing the latter to break down and ask that Eren kill him.

Helping Reiner to his feet, Eren says that he now understands that they are the same and declares that he will continue until he wipes out his enemy. Transforming into the Attack Titan, Eren breaks out of the building and kills Willy. He flings himself on top of the military high command in the crowd, killing them. As Eren rampages, the War Hammer Titan emerges and he attacks it before it can fully transform. It appears he has the upper hand until a hardened pillar impales him.

The War Hammer Titan finishes its formation and constructs a hammer to fight Eren. Eren breaks the pillar trapping his Titan only to find the ground covered in barbed spikes, preventing him from lifting his feet. Eren hardens his Titan's hands in an attempt to block the War Hammer's next strike, but fails, and the Attack Titan's head is sheered away. Eren emerges from his Titan's nape and calls for Mikasa, who attacks the War Hammer at the same time the rest of the Survey Corps attack the Marleyan military.

The War Hammer Titan survives Mikasa's attack and fires a pike of its hardened skin towards them. Mikasa grabs Eren and flees from the Attack Titan's body, barely evading the pike. Eren comes up with a plan to defeat and eat the War Hammer Titan, and asks Mikasa to distract it long enough for him to enact it. As Mikasa fights the War Hammer Titan, Eren remembers that the Titan's body materialized from its feet rather than its nape and deduces that its human body is located somewhere underground. Transforming back into the Attack Titan, he sees a hole in the street from where a long cable of flesh comes out, attached to the War Hammer Titan. Eren reaches in and grabs the crystallized body of the younger sister of Willy, severing her connection and disabling the War Hammer.

As Eren is about to eat the War Hammer, the Jaw Titan appears behind him and bites Eren's neck. With Levi's help, Eren smashes the Titan against the building and tries to take it off his back, but it manages to flee. Because of the distraction Eren fails to notice that the War Hammer has been generating a new Titan body and he is impaled in a tree-like structure made of hardened skin. Trapped, Eren breaks his hand free and attempts to consume the War Hammer's user once more. When he bites the crystal, he breaks his Titan's jaw on the hardened surface. Eren exits trapped Titan form and immediately transforms once again. The Jaw Titan runs across the plaza to assault Eren, and resorts to using its claws to strike him. During the attack, Eren blocks a slash from the Titan using the younger sister of Willy's crystal. Noticing that the attack successfully produced cracks in the crystal, Eren devises a plan to use the Jaw Titan to get to the younger sister of Willy.

Mikasa cripples the Jaw Titan's legs in a surprise attack, allowing Eren grabs it and disables it before jamming the crystal into its mouth and using its jaws to break through. He successfully kills the younger sister of Willy, consuming the fluids from her body and giving himself the powers of the War Hammer Titan. He moves to finish off the Jaw Titan but is stopped by the arrival of an incomplete Armored Titan. Eren punches Reiner, but Reiner manages to rescue the Jaw Titan. Eren emerges from his Titan, proclaiming that their mission is done, leading Mikasa to ask that they go back home. As they grapple up to the airship, Eren promises Reiner that they will meet again.

Once on the airship Eren is met by Levi, who kicks him and orders that he be restrained. Eren does not resist, but insists that nothing in his letter was wrong. Eren waits in a room with Zeke and Yelena aboard the airship when Jean arrives with Falco and Gabi, saying that Gabi shot Sasha. Hange berates Eren for having forced the Survey Corps to accommodate his plans and abusing their trust. Eren is unrepentant, saying that the destruction of the Marleyan military leadership has bought them time. When Connie comes in to announce that Sasha has died, Eren asks about her final words. Hearing that it was "meat," Eren begins to laugh.

After returning to Paradis, Eren is taken to a cell underground in accordance with his arrest. As he cleans himself up, Eren mutters that Paradis needs to continue fighting.

War for Paradis arc
Hange arrives and notes that Eren was talking to himself before attempting to make small talk with him. Eren demands to know what Hange visited him for and Hange chastises Eren for inflaming the rest of the world against Paradis with his attack. Eren reveals that he stole the power of the War Hammer Titan in Liberio and claims that he can free himself any time. Grabbing Hange through the bars of his cell, Eren demands to know what Hange can do to him, and asks if there is any other way for them to act.

At roughly the same time Darius Zackly is killed by a bomb in his office, Eren uses his Titan abilities to escape from his cell. He seals up his exit route with hardened skin to prevent his captors from following him. After escaping, Eren meets up with the Yeagerists, a group consisting of Floch and the other recruits who sided with him during his incarceration. Eren declares that they need to locate Zeke.

Eren hears the proposal put forth by Commander Pixis and refuses the offer. He instructs his followers not to negotiate with the Military. He then learns from one of his followers that Hange and his friends are gathered at a nearby restaurant. Arriving at the restaurant, he instructs Floch to restrain and move them while he speak to Mikasa, Armin, and Gabi. Eren speaks to them in a private room, claiming to want to solve things peacefully. Armin asks if Zeke and Yelena have convinced him to join their side, but Eren brushes him off and claims that everything he has done has been his desire. Mikasa insists he is being controlled but Eren ignores her.

Eren reveals to Armin that he is aware of the latter's frequent trips to visit Annie and suggests he is being unknowingly influenced by the memories Bertolt had of her. When Mikasa goes to defend Armin, Eren reveals that he has learned about her family lineage from Zeke and claims that the only reason she has stayed by his side is due to her instincts to protect her host. He explains that Ackermans, once awakened, often suffer unexpected headaches due to their true self fighting the urge to protect their recognized host and claims the true Mikasa died the day he saved her from her kidnappers. Eren proclaims that he has always hated people like Mikasa: obedient slaves that do nothing but follow orders. Armin attacks Eren, but his point is proven when Mikasa instinctively grabs Armin and slams him into the table. Armin manages to punch him anyway and Eren responds by beating Armin into submission. He orders that they and Gabi be taken away, but becomes briefly enraged when Armin calls him a slave.

Later, Eren takes two soldiers and visits Gabi in her holding cell and offers to help her save Falco in exchange for her issuing a call for help to Marley to root out any possible spies. Eren is caught by surprise when one of the soldiers aims a pistol at him after stabbing the other in the throat. He is unfazed by Pieck's threat of shooting him, reminding her that her mission is to presumably take him alive. However, Pieck claims that she wishes to join him. Not trusting her intentions, Eren pricks his finger and orders her to prove herself to him and the Yeagerists. When Pieck offers to reveal where her fellow infiltrators are, Eren heals his finger and orders Pieck and Gabi to be handcuffed together.

On the roof, he prepares to injure himself again and orders Pieck to reveal her fellow infiltrators. She points at Eren himself, and the Jaw Titan suddenly attacks Eren, taking both of his legs. Transforming, Eren spots a fleet of Marleyan airships approaching their location. Eren trades several blows with the Jaw Titan before it retreats. Eren is perplexed at Marley's decision to launch a counterattack so soon after the raid on Liberio. Despite Yelena pleading with him to flee underground, Eren decides to fight Marley on his own. Noticing Reiner transforming into the Armored Titan while parachuting from an airship, Eren deduces that was responsible for Marley's quick response to the Liberio attack and the two proceed to engage each other.

Eren initially overpowers Reiner, using his superior fighting skills and hardening to break through Reiner's armor plating. Reiner manages to briefly stun Eren and the Jaw Titan attempts to ambush him from behind but Eren uses the War Hammer Titan's abilities to repel them. Eren is shot in the head with a round from Marley's anti-Titan artillery, leaving his motor skills severely impaired. Eren is able to generate more spikes to stop the Jaw Titan's attacks but is shot in the head a second time. Stunned, Eren is unable to dodge Reiner's attack and is skewered by one of the spikes generated from the ground. Despite this, he manages to generate a third set of spikes to impale Reiner once more, and smacks the Jaw Titan out of the air when it tries to attack him from behind. Eren tries to hold off Reiner and manages rip through the latter's jaw but Reiner continues to incapacitate Eren until he is saved by a projectile thrown by Zeke from atop the Wall.

With Zeke's arrival, Eren begins trying to reach him in hopes of activating the powers of the Founding Titan while Zeke keeps Marley's Warriors at bay. As he grows closer to Zeke's position, Eren is set upon by the Jaw Titan once again but makes short work of him, repeatedly slamming down on the Titan's head and nape. However, this distracts him long enough for another anti-Titan artillery round to be fired into his head again and for Reiner to catch up to him and begin grappling with him. The fighting is momentarily interrupted by the arrival of Colt and Falco who reveal that Falco has accidentally ingested Zeke's spinal fluid. Zeke is undeterred and screams, ordering a transformed Falco to attack Reiner. Falco's Pure Titan does not prove to be enough to force Reiner to let go of Eren, so Eren exits his Titan and begins running to Zeke on foot. However, before he can reach his brother Eren is decapitated by a blast from an anti-Titan artillery rifle.

As his head lands in his brother's hand, Eren suddenly finds himself standing before a pillar of light in an unknown land. He is greeted by a chained Zeke, who informs Eren that they are standing in the Coordinate. Zeke explains that he was able to bring the two of them into the unknown land by touching Eren's head in the moments before he could die. They have finally unlocked the Founding Titan's power.

Eren notices a young girl approaching them and Zeke informs him that the girl is Ymir Fritz. Zeke encourages him to take control of Ymir and activate their plan to euthanize all Eldians, but Eren inquires as to why he is sitting there in chains. Zeke explains that the chains are Karl Fritz's vow, keeping anyone with royal blood from acting freely and again asks Eren to begin their plan. However, Eren reveals that he has no intention of following Zeke's plan and was only using him to obtain the Founder's power. Eren approaches Ymir and requests he be given control of her power, only to be ignored. To Eren's horror, Zeke reveals that during his time waiting for Eren to arrive in the unknown land he discovered a way to erase Karl Fritz's vow, and that Ymir will only obey people with royal blood. Zeke chains Eren in place, explaining that he has been brainwashed by Grisha. Despite Eren's protests, Zeke promises to free him and begins showing him memories from Grisha's life.

Zeke systematically takes Eren through different moments in Grisha's life on Paradis, detailing how Grisha covertly used his occupation as a doctor to gain information on the royal family in spite of the risk posed to his new family. Eren is largely unfazed by the memories, only surprised to learn that Grisha located the Reiss chapel years before he actually attacked the family and that he still thought of Zeke years after arriving to Paradis. While Zeke is reeling at the revelation that their father still cared for him, Eren moves along to the next memory. As Eren and Zeke continue through Grisha's memories, Zeke asks why Eren betrayed him if he was not brainwashed by Grisha. Eren responds that he has always believed in stealing the freedom of anyone who opposes his own. Eren and Zeke then go to the memory of Grisha writing about how humanity has not perished beyond the walls, and are both caught off guard when Grisha is able to see Zeke for a brief moment.

Eren and Zeke travel to Grisha's memory of the day he stole the Founding Titan from the Reiss family. As he observes the exchange between his father and Frieda Reiss, Eren becomes increasingly agitated by Frieda's claims that the Eldians must take on the world's wrath for the sins of their ancestors. Despite Grisha's declaration that he will steal the Founding Titan from the Reiss family, Eren is disappointed and enraged to see that his father cannot bring himself to carry out his mission. To spur his father forward, Eren reminds Grisha of his fellow restorationists and Faye, ordering him to finish what he has started.

Zeke returns the two brothers to the present, despite Eren's objection that they have yet to see Grisha's final memories. Eren reveals that four years prior he had been given a glimpse of his own memories of the future while peering into Grisha's memories and Zeke, horrified, orders Ymir to sterilize the Subjects of Ymir. Desperate to stop Zeke's plan, Eren is able to escape his chains by severing his thumbs against the shackles and races to try to stop Ymir. He embraces her and begs that she give him her power so that he can end the world, promising that he will not force her to help him. He recognizes that she is neither a slave nor a deity, she is only a human being and she has the right to choose if she wants to remain in the Coordinate forever or help him end it all. As Zeke desperately tries to stop him, Eren asks Ymir if she was the one who led him to the Coordinate, musing that she has been waiting 2,000 years for him to arrive.

In Shiganshina, Eren's body transforms into the Founding Titan as Shiganshina's walls begin to crumble. He then uses the Founder's power to telepathically communicate with all of the Subjects of Ymir. He reveals that the hardening of the Walls has come undone, and declares that the Wall Titans will destroy all life outside the island.

Eren and his Titans arrive at Marley's coast to find it guarded by the Global Allied Fleet. However, the fleet proves to be ineffective against Eren's Colossus Titans and is immediately wiped out. The land artillery on Marley is also unsuccessful in stopping the advancing Titans, causing the soldiers to retreat to higher ground. As his Titans begin the destruction of Marley, Eren remembers the death of his mother and reiterates his desire to destroy every last one of his enemies in the world.

As he approaches Fort Salta, Eren summons Mikasa, Armin, Jean, Connie, Levi, Reiner, and Pieck into the Paths to speak to them. His former comrades beg him to stop the Rumbling, but Eren tells them that he has no intention of stopping. He explains that he will take all of the world's freedom so he can achieve his own, but he promises not to deny the alliance's freedom to thwart his plans. However, Eren reinforces his intent to destroy the world, refusing to negotiate on any terms and stating that the only thing to stop his advance would be his death.

Marleyan airships are launched from Fort Salta in an attempt to stop Eren's advance and begin dropping bombs on his Titan. In response, Eren dispatches the Beast Titan to shoot them down. Eren and the Beast make quick work of the airships, but his former comrades arrive and manage to evade the Beast Titan's projectiles long enough to reach him and engage him directly. As his friends attempt to reach his nape to destroy it, Eren and Ymir begin generating more Titans on his back to defend him. Despite this, the soldiers eventually manage to reach Eren's nape and blow it up, severing his Titan's head from its body. Armin then transforms atop his Titan in an attempt to kill him.

This proves to be ineffective, and Eren's head transforms again into a new Colossus form to continue its march. He is met by Armin, who chooses to engage him in a hand-to-hand fight with his Colossus Titan form. Eren once again proves to be the better fighter between the two, but Armin manages to immobilize him long enough for Mikasa to enter his Titan's mouth and mortally wound him.

Martial arts
Originally, Eren's only noteworthy trait was his natural physical strength, which stemmed from having to defend his friend Armin from bullies who were bigger and stronger. As he grew and joined the 104th squad, he trained extensively in hand-to-hand combat. After additional training with Reiner and Annie, Eren's prowess and skill set diversified, including the use of punches, throws, grappling and submission locks. He had the best scores for hand-to-hand combat of the entire 104th graduate squad. While hand-to-hand fighting would appear useless due to the massive physical differences between humans and Titans, these skills gave Eren a powerful edge when fighting other Titans in his own Titan form.

Vertical maneuvering equipment
Though having little talent, through intense training and effort he managed to gain a considerable amount of skill with the equipment. Even so, Eren was not completely lacking in natural aptitude. While using the damaged equipment, he had managed to stay upright for a short amount of time, which the instructor, Keith Shadis, said was an incredible feat, and balanced with ease when using proper gear. The fact he graduated as the 5th best of the 104th graduate squad, even before Jean Kirstein, who was top of the class in mobility with the gear, implied that he had considerable combat skill with the maneuvering equipment.

Though Eren was not shown using the equipment as often as other members of the Survey Corps, he was able to hold his own against the Colossus Titan until the Titan disappeared, almost reaching the nape twice. He was even capable of killing a Titan on his own not too long after joining the Survey Corps. His most significant use of maneuvering equipment was shown during the Battle of Shiganshina, where he was able to use it to cut Bertolt Hoover out of the Colossus Titan's nape while he was distracted by his hardened Titan form, despite being exhausted.

Attack Titan
After the fall of Wall Maria, Grisha found Eren in a refugee camp and brought him into a nearby forest. After giving him the key to the basement, Grisha injected a struggling Eren with a serum, which transformed him into a 4 meter Pure Titan with short rugged hair and a skinny body. This Titan ate Grisha, giving Eren the powers of the Founding Titan and Attack Titan. Years later, during the first Battle of Trost, Eren was eaten alive by a Titan, and inside the stomach-like cavity saw other fellow recruits lying dead/dying, one wanting her mother before sinking in stomach acid. The sight combined with intense feelings of desperation and his drive to exterminate all Titans awoke his ability to transform into his Titan form for the first time.

In this form, Eren is a 15 meter tall Titan, with shoulder-length black hair, pointed ears, a long nose, and a gaping, skeleton-like maw lacking lips. Unlike most other Titans, his Titan form is considerably more muscular and defined; making him much stronger than even similar-sized Titans while his intelligence and military training, allow him to out-maneuver and dispatch entire groups of Titans with ease. A transformation takes a heavy toll on Eren’s body and requires large amounts of stamina. As a result, he has displayed several symptoms when he over-exerts himself such as a nosebleed, pale skin, and labored breathing. In some cases, Eren is rendered unconscious for a short period of time after a Titan transformation.

Initially, Eren has no control over his actions when he first transforms into a Titan and is unable to remember any actions that occurred during the first Battle of Trost. He is in a “dream-like state” and fails to remember how to transform in the first place. However, Eren recalls fragmented memories of his father by seeing the key to the basement of his old home and is able to successfully transform to protect Armin and Mikasa from certain death. It has been shown that with more transformations, Eren retains more of his intelligence, being able to form rational thoughts. At the beginning, during the second Battle of Trost, Eren in his Titan form attacks Mikasa but ultimately plugs the hole in Trost's gate after Armin forces him to wake up. His Titan form, combined with his growing experience and his hand-to-hand combat skills, allowed him to kill over 20 Titans in his first transformation and later manage to overpower and nearly kill the Armored Titan.

Eren, like all others with the power of the Titans, must physically harm himself (or suffer some kind of injury) in order to transform into his Titan form. However, lack of a determined goal and resolution for it inhibit his ability to transform as shown when he cannot transform at first to confront Annie Leonhart. Within Titan transformations, he has displayed the ability to partially transform, as shown when he protected Mikasa and Armin from a cannonball by forming the upper torso skeleton, complete with arms and a skull with some muscle tissue.


 * Enhanced Strength: As a result of Eren’s Titan form being much more muscular than other Titans, he is much stronger in terms of physical strength. During his first transformation, Eren was able to decapitate a 15m Titan with a single punch and kill a 7m Titan with little effort. With both arms lost, he was also strong enough to bite into the neck of a large, abnormal Titan that ate Thomas and lift it up above his head. With enough force, Eren was able to throw the abnormal into another Titan hard enough to knock them both into a building. Against the Female Titan in the Titan Forest, Eren’s Titan form had enough physical force to leave large craters in the ground, as well as lift the Female Titan into the air with a punch. Ultimately, Eren’s greatest display of strength was when he lifted a giant boulder, albeit with difficulty, carry it across a large distance, and slam it down to seal the hole in Trost's gate, producing a large shock wave.
 * Enhanced Endurance: Perhaps Eren's most notable trait of all is his ability to maintain levels of activity for an extended period of time. His first transformation carried on long enough to incapacitate 20 Titans in total. In battle, even after receiving massive amounts of damage from the Female Titan, Eren can carry on fighting, despite the handicaps that he suffers. He was also able to fight against the Armored Titan for a period of time and gain the upper hand. Eren’s endurance in his Titan form was enough to allow him to sustain the effort of hoisting a huge rock on his back, carry it over a large distance, and seal the hole in Trost's gate shortly before collapsing. In Marley, Eren displayed exceptional improvement in his durability. He could transform into a Titan three times in one battle, surprising Galliard.


 * Hardening: After drinking a bottle labeled "Armor" from Rod Reiss's bag, Eren's Titan form gained the ability to harden its body, as well as create a web of pillars that appear to originate from his Titan body. The hardened pillars are incredibly durable, capable of preventing a cave-in, as well as shielding Squad Levi from the heat of Rod Reiss' Titan form. The constructs, as well as Eren's Titan, also retain their durability and hardened state even after he has been separated from his Titan body. After two months of training with Hange Zoë, Eren is able to seal a cave with his hardening powers and reinforce the hole the Colossus Titan left in Trost. However, constant use of this power can overwhelm Eren and make him weak. By focusing his hardening in one place, it gets even stronger. Focusing in his fists gives Eren a hardened punch, capable of easily breaking the Armored Titan's face armor. In Marley, Eren's improved hardening abilities let him harden his forearm fast enough to block a hardened spike from the War Hammer before it could pierce his nape.
 * Regeneration: Eren’s Titan form has demonstrated the ability to automatically heal any injury sustained in battle and also to regenerate entire limbs. Unlike Annie Leonhart, Eren has not shown the advanced ability to focus regeneration to one wounded area of his Titan form. His healing factor was fast enough to heal an entire lost hand in mere seconds to an entire arm in minutes. This ability is useful to Eren as, when he fights, he often loses entire limbs in his Titan form. While in his human state, Eren can also regenerate entire lost limbs, as seen by regrowing an arm and leg he lost to Titans. When captured by Reiner and Bertolt in the Titan Forest, Eren was seen regenerating his lost arms after he lost a fight in his Titan form. During his infiltration mission in Marley, Eren has mastered this ability to the extent that he can restrain the regeneration of his left leg in order to disguise himself as an injured soldier.
 * Future Memory Inheritance: As part of the Attack Titan's unique abilities, Eren can reveal his own memories to his predecessors, giving them insight into the future. He gives memories of the future to his father Grisha, selecting the ones that would suit his purpose. By doing so, he indirectly gives his younger self insight into his own future via Grisha's memories when Eren kisses Historia's hand.

Founding Titan
With the power of the Founding Titan that Grisha Yeager stole from the Reiss family, Eren possesses the ability to control nearby Titans, causing them to relentlessly attack his chosen target. However, this ability can only be used while Eren is in contact with a Titan of royal blood.

The first time he uses it is entirely by accident, by touching the palm of Dina Fritz's Titan, causing nearby Titans to attack and devour her, and setting the same Titans upon Bertolt and Reiner. While it is shown that others with the power of the Titans can sense the activation of his power, it is unknown whether it is possible to use it to influence or control other human-controlled Titans.

Possession of the Founding Titan is the reason many groups have expressed an interest in Eren, including Marley's Warriors in their Paradis Island Operation, and Rod Reiss, the former patriarch of the Reiss family.

Four years after Eren's first, and accidental use of it, Eren is finally able to unlock the full capabilities of the Founding Titan after freeing the soul of Ymir Fritz from the control of her descendants, giving him access to all of the Founder's powers. With the full power of the Founder, Eren is able to control all of the Wall Titans, create a unique Titan body that towers over all of them, and can telepathically communicate with all of the Subjects of Ymir.

War Hammer Titan
Eren obtained the power of the War Hammer Titan during the Raid on Liberio by devouring the younger sister of Willy. He is capable of using the War Hammer's abilities to create defensive pikes and caltrops to hinder his enemies in combat. He is also capable of sealing a long tunnel with hardened Titan flesh to evade capture.

Relationships

 * Grisha Yeager - Eren greatly looked up to his father Grisha, who usually supported his son and did not show any visible objections to Eren's wish to join the Survey Corps when he was old enough to enlist; he did express some frustration and later sadness by his father's sudden disappearance after Wall Maria fell. Upon remembering the mission his father left him before he vanished, Eren expressed anger and bitterness at the fact that Grisha had kept secrets from them, on top of abandoning himself and Mikasa. Eventually, Eren is shown memories of his father thanks to Historia and Rod Reiss in which he learns his father had indeed returned after the fall of Wall Maria; in addition, Eren also learned that his father was the one who gave him his powers and he was dead because Eren devoured him. Eren became distraught upon realizing he killed his own father but became horrified that the latter was a Titan that killed the Reiss family. He tried to persuade Historia that they do not have to follow the wishes of their fathers, showing he gained some resentment for Grisha. This would last for several years until he saw his father's memories and saw why he kept his past a secret from him. This gave Eren a better understanding of his father's actions and why Grisha kept secrets from his family. This understanding was seen again after he met his grandfather who broke down after reflecting on his past treatment to his son. While appreciating his father, Eren expressed frustration at Grisha's reluctance to take the Founder and influenced him in order to fulfill his duty.
 * Carla Yeager - Eren clearly loved his mother Carla very much, although they would constantly argue over his wish to join the Military and as a result would often ignore her warnings or advice. During the fall of Shiganshina, he struggled in vain to rescue her from the rubble of their demolished home despite being surrounded by Titans and wanting to run away from the danger. Unfortunately, he was ultimately forced to watch a Titan devour her as he was hauled to safety. Her brutal demise and his own powerlessness to prevent it severely traumatized Eren. In his grief, he expressed remorse for continuing to disobey and argue with her in their last moments together, and her loss fueled his virulent hatred of all Titans. As he contemplated the future years later, he would ponder on his mother's opinion of the oncoming calamity he would inflict on the world.
 * Hannes - Prior to the fall of Wall Maria, Eren was constantly frustrated by Hannes being a habitual drunkard in the line of duty. Despite not having saved Carla from the hands of the Titan, Eren borne no ill will towards him, and instead looked up to him with respect and understanding. Eren was driven to the brink of despair as he witnessed Hannes being eaten alive by the Smiling Titan, and he remains tormented by his loss despite managing to avenge him. In memory of Hannes and his sacrifice, Eren has become more determined than ever to discover the truth about the Titans and punish any guilty parties.
 * Mikasa Ackerman - Eren has a complex relationship with Mikasa. He often displays a brusque, casual attitude with her, which belies their deep bond and care for each other. While Mikasa is more open with showing concern for him, Eren only does so when she is injured or in distress. Despite his blunt exterior, he is always looking out for her, and will not hesitate to comfort or reassure her when he senses that she needs him to. He would even go as far as to call himself a monster to ensure that she would not be targeted by the prosecution. They do not always agree, but Eren will usually not stop Mikasa from doing what she wants, so long as it is within reason. He also seems to harbor somewhat of an inferiority complex towards her, due to her outstripping him in both strength and battle skill. This is further compounded by her desire to constantly keep tabs on him and keep him out of trouble - a habit he generally views as annoying. At times, he feels so stifled by her protectiveness that he openly lashes out at her, telling her not to treat him like her "little brother." Despite this, he will attack anyone and anything that threatens Mikasa, even meeting a punch from a 14 m class Titan bare-handed simply to protect her. After going across the sea, Eren asks Mikasa about what he means to her. When she replies that he is family, the rest of their friends arrive and interrupt them, disappointing Eren. After joining the Yeagerists, Eren breaks all ties with Mikasa and the Military; when Mikasa tries to bring him around, he calls her an obedient slave and claims that she has become the thing he hates most in the world. While this deeply hurts her, she was willing to support Eren when Marley launches a counterattack on Paradis following the raid on Liberio, but chooses to leave behind the scarf he gave her years ago. After Eren announces that he has started the Rumbling, Mikasa was horrified at this revelation, but she was later unable to respond to Annie when she was asked if she could kill Eren when necessary. Mikasa is still willing to hold out hope for Eren to come to his senses.
 * Armin Arlert - Armin was Eren's closest friend, who inspired him to dream of the world beyond the Walls (and in doing so, became partially responsible for motivating him to join the Survey Corps). During their childhood, they were snubbed by other children as well as adults for their "heretical" ideas. Armin himself is frequently targeted by bullies, whom Eren (sometimes with Mikasa in tow) would constantly try to fend off. This pattern would continue into their teenage years, with Eren leaping into action to save Armin from danger, not caring if he himself is harmed in the process; the most memorable occasion being the day Eren (sans his left leg) snatched Armin from a Titan's jaws and got swallowed in his place (losing his left arm in the process). Despite Armin considering himself as burdensome, Eren greatly appreciates his quick-wittiness and brilliant judgment (it also did not miss him that Armin's quick thinking had saved his and Mikasa's lives in 845). Eren's confidence in Armin is so great that he would entrust him with his life with no hesitation if asked to do so. When Levi forced to revive Armin or Erwin, Eren desperately pleads Levi to revive Armin, staging a mutiny to try and save his friend, and when Armin is brought back, Eren rushes toward him with tears of relief flowing down his face, embracing Armin after he regains consciousness. However, four years later, some friction has developed between them due to differing opinions on how to deal with Marley and the other nations. Like Eren's relationship with Mikasa, his friendship with Armin is presumably shattered after he joins the Yeagerist movement. Later, Armin correctly deduced that Eren is only pretending to go along with Zeke's plan, realizing that Eren is just using Zeke to unlock the Founding Titan's powers. After Armin realizes that Eren has started the Rumbling- shortly before Eren's revelation- he numbly contemplates the consequences with Jean. Despite this, he is still unsure of even thinking about killing Eren, as demonstrated many times in his conversations with Annie. Armin still hopes that he and Eren could still discover the world together.
 * Jean Kirstein - As Eren's main rival, his temperament is the very antithesis of Eren's. Where Eren is hotheaded, he is collected; and Jean is pessimistically pragmatic as Eren is idealistic. Jean believed anyone who wished to join the Survey Corps was a suicidal fool, while Eren regarded those who looked down on the people who wanted to fight the Titans with contempt. Initially, they are able to resolve their differences in a civil manner despite starting off on the wrong foot. However, this friendliness was short-lived, and a fierce rivalry budded between them, with the two constantly provoking each other and getting into fistfights. In addition to insulting Jean to his face, Eren also seems to be fond of saying Jean has a "horse-face" behind his back. In the wake of the Battle of Trost, Eren and Jean seem to have set their differences aside and stopped antagonizing each other. Though they still quarrel as much as before, their animosity has noticeably lessened. After Eren reveals his genocide plan, Jean was willing to justify Eren's actions as a measure of self-defence; sacrificing the rest of the world for Paradis' safety.
 * Levi Ackerman - As humanity's most formidable soldier and Eren's superior officer, Levi commands great respect and admiration from him. Eren bears no grudge against Levi for beating him before the entire court during his trial, recognizing that it had been a necessary measure to secure his life. Aware of the vast gap in experience between them, Eren strives to learn as much as he can from Levi, heeding his advice with little hesitation and trusting his judgment. During the thirty days he shared living space with Levi's squad, he also seems to have well understood Levi's standards of cleanliness. A notable example of this is when he is shown diligently cleaning his new squad's base (and fretting over the somewhat slovenly habits of his peers) in anticipation of Levi's arrival. As Eren has spent more time with Levi and witnessed how harsh he can be to his peers, he is able to marvel at and encourage the notion of punching Levi back. Later, Levi becomes a sort of mentor towards Eren, giving him advice in his times of doubt. As their trust in each other grows, Levi becomes more patient with Eren and forgives his mistakes, nurturing his growth as a soldier, and as a vanguard for humanity's hope. In spite of this, Eren would break Levi's trust and respect when he orchestrated the raid on Liberio, physically reprimanding his insubordination and arresting him after the battle.
 * Erwin Smith - Eren briefly meets Erwin as a child the day Shingashina when the Survey Corps returns from a mission. Erwin sees Eren in the crowd smiling in awe but Erwin looked away in sadness due to the heavy losses sustained. Five years later Eren is officially introduced to Erwin following the Battle of Trost and Erwin expressed interest in recruiting hin into the Survey Corps so they could reclaim Wall Maria, and acted in Eren's defense during his hearing. Though Eren was at first discomforted by Erwin's willingness to take big risks and endanger lives he gradually came to understand Erwin's actions when faced with increasingly dangerous threats to humanity.
 * Reiner Braun - Eren once described Reiner as being like an older brother to him, and admired him as a "strong, capable guy." The two were shown to have trained together, and Reiner taught him the importance of the duty soldiers have to protect the weak. It can be said that he was the one Eren looked up to the most in his career as a soldier. However, Eren eventually came to despise Reiner upon learning of his true identity as the Armored Titan and began to view him as a disgusting traitor who had no right to be alive. He planned to slaughter him along with Bertolt Hoover in the slowest, most excruciating manner possible in repayment for all that they had done. When they meet again four years later, Eren's contempt towards Reiner seems to have mellowed to some degree, expressing to Reiner that it is good that he had managed to return to his hometown. In return, Reiner was shocked by Eren's presence and could barely say a word to him. Eren expresses a newfound sympathy towards Reiner after learning the truth about Reiner's mission within the Walls and the world's hatred towards Eldians and experiencing the same infiltration mission within Marley that Reiner carried out years before. Eren even admits he and Reiner are the same, driven by freedom for their people and manipulated by corrupt leaders for the actions of their ancestors. Eren even admits his own anger towards Reiner and Bertolt (and that his promise to make their deaths as miserable and painful as possible) was rash due to him not knowing their reasons why. Despite this Eren still tries to kill him, although implies it is not out of malicious intent but because they are on opposing sides of the war. It is revealed that Eren thinks they are the same but he internally denies this and considers himself lower than Reiner.
 * Bertolt Hoover - When Eren first met Bertolt, he had some reservations about him and seemed to think of Bertolt as "taciturn." Regardless, Eren came to trust Bertolt and saw him as a valued friend. After his true identity as the Colossus Titan was revealed, Eren was horrified and despised Bertolt for causing the death of his mother; this inspired Eren to seek vengeance on all Titans with Bertolt being the main target of his mission. He was only further infuriated by Bertolt's cold response and became bent on making his death as miserable and painful as possible. Eren eventually made good on this promise, personally ripping Bertolt out of the Colossus Titan and severing his limbs, leaving him helpless against the pure Titan of Armin Arlert. Despite this, however, Eren ultimately did not revel in Bertolt's death; rather, he silently cried with a stunned expression on his face as he watched him being eaten. Four years later when Eren meets Reiner again, he admits his promise and anger towards him and Bertolt was misguided since he did not understand their motives at the time. Eren also seems to acknowledge in his forgiveness towards Reiner that Bertolt was as much a victim as they were.
 * Annie Leonhart - Eren greatly admired Annie, and was trained in her unique fighting style during their years as trainees. He considered her to be a kind person beneath her cold exterior and credited her with making him aware of the contradictions within the military system. However, he was eventually horrified to learn of her identity as the Female Titan. Even as Annie herself transformed in front of him, a part of Eren refused to accept her betrayal; and he became so conflicted that he was initially unable to summon the will to fight her (Mikasa even went so far as to suggest that his hesitation was due to him harboring "special feelings" for her). Even as he went toe-to-toe with Annie, he continued to brood over what had driven her to slaughter their comrades and displayed far less anger and contempt towards her than he did for Bertolt or Reiner.
 * Historia Reiss - Initially, Eren did not interact with Historia very much, and had in fact secretly disliked her because he felt she was a phony. However, once her true identity was revealed and her demeanor began to change, Eren began to see her as more "honest" and warmed up to her. He even accepted being eaten by her if it meant the annihilation of all Titans, which shows deep confidence in her. Despite this, he still wishes for Historia to lead her own life. Eren omitted that coming into contact with a royal blooded Titan would enable him to use the Founding Titan's abilities, fearing that sharing information he considered uncertain at the time would cause Historia to be turned into a Titan. Eren also argues against the plan of Historia being used to birth more heirs to the royal bloodline and becoming the next inheritor of the Beast Titan, showing that Eren cares for her deeply. However, he was not above pressuring Historia into not divulging his genocide plan, showing duplicity in his actions.
 * Connie Springer - As members of the same trainee squad, Eren and Connie shared many experiences together and get on well with each other. In the early days of their training, Connie was among the trainees who eagerly questioned Eren about the Titans' invasion in 845. Though he only enlisted in order to have a good reputation in his home village and initially wished to join the Military Police Brigade, Connie was so moved by Eren's passionate conviction to defeat the Titans that in the end, he decided to join the Survey Corps instead. Though their backgrounds are different, the two now find themselves sharing a similar plight. Both their families and homes are reduced to little more than memories, and each carries the burden of his mother's cruel fate. However, following Sasha's death and Eren's seeming indifference in having a hand in it, Connie starts viewing Eren contemptuously and sees him as a different person from the one he befriended, and states he is ready to kill Eren should the need arise.
 * Hange Zoë - When Eren first met Hange, he was put off by their obsession with him, finding it creepy. After learning about Hange's work on Sonny and Bean, however, and Hange's reason for being so obsessed with Titans and change (which he could relate to), he became one of the first people to be interested in their work and was saddened by the deaths of the Titan test subjects (although he still found Hange weird, especially after they kept him up the entirety of one night). After four years, their relationship sours when Hange noted that Eren's actions in Liberio made the entire Paradis Island a target to Marley; furthermore, Hange expressed anger over how Eren abused the Survey Corps' trust in him for his own selfish desires. Their relationship took another blow when Eren physically assaulted Hange, slamming them against the bars of his cell after returning from Marley and being arrested for his actions.
 * Marco Bott - Eren had great respect for him, and recognized his tendency to think of the group before himself. He also stated he would have liked to be on his squad, and considered him a good leader. Upon learning of Marco's death, Eren was initially in a state of disbelief and was visibly stricken when Jean reaffirmed that the news was indeed true.
 * Petra Ral - Among the members of the squad assigned to protect Eren, Petra seemed to be the one closest to him. She was among the least eccentric and most friendly of the members, and Eren admired her not only for her skill but for her open acceptance of him as a comrade as well. Witnessing her demise at the hands of the Female Titan was a devastating blow to him, and he remains remorseful of making the decision that led to her death.
 * Oluo Bozado - Of all the members of Levi's squad, Oluo gave Eren the toughest time, often badmouthing and blustering at him. Despite his senior's somewhat obnoxious and boastful demeanor, Eren still respected Oluo as a top-tier soldier. In return, Oluo once threatened Eren but saw his mistake and apologized for it though he said so in his arrogant ways. His violent death was perhaps the trigger event that caused Eren to finally transform into his Titan form to stop the Female Titan in its tracks. Along with the other members of Levi's special squad, his death still haunts Eren.
 * Eld Jinn and Gunther Schultz - Eren admired the two soldiers; both in their skills, serious attitude and devotion to humanity by facing the Titans. Their deaths partly fueled Eren's rampage against the Female Titan, and he is still filled with regret over not choosing to fight while they were still alive.
 * Zeke Yeager - Zeke is Eren's older half-brother. Though they initially did not have much interaction, Zeke told Eren that he understands him and wants him to believe him that they both were victims of their father's brainwashing and said that someday he will come to save him. Eren was very surprised Zeke had a resemblance to his father and wondered about the connection until he saw his father's memories and discovered their relationship, becoming shocked that his father had a previous family. Of particular note, Zeke's turning on their father indirectly led to Eren's birth and he also learned that Zeke's mother was the Titan that killed Eren's mother. Four years later, Eren meets his brother in secret, learning numerous secrets and creating a mutual understanding between them. The two now work together, and plan to meet once again to set in motion their secret plan. However, Eren later reveals he lied to Zeke and ultimately refuses to go along with the latter's euthanasia plan. Following the revelation that Eren used the future memory inheritance ability of the Attack Titan to compel their father into killing the Reiss family and steal the Founding Titan, Zeke becomes disillusioned with his brother.
 * Falco Grice - Eren seems to have taken a liking to Falco as seen with his friendly demeanor when he saw Falco in the hospital and often spent time talking with the young Warrior candidate; regardless, Eren had no issues with manipulating him into unwittingly send messages to the Survey Corps for him. Despite his dismissive nature towards Falco after his true motives are revealed, Eren does exhibit some regret that Falco was among those who unknowingly consumed Zeke's spinal fluid.
 * Mr. Yeager - Eren saw his grandfather through his father's memories but what opinion he had of him was unknown. Four years later, he met his grandfather in person while disguising himself as a wounded soldier. He was surprised by the latter's appearance but kept it to himself to avoid suspicion. In a talk, Mr. Yeager appeared to be aware of Eren having Falco do errands for him and told him to stop as it might bring trouble for his family. Mr. Yeager soon confided in him about his past which led his son to form a movement and slowly blame himself for raising him to follow in his footsteps. Eren was solemn at his grandfather's outburst but appeared to understand the choices of his father.
 * Floch Forster - Eren did not think highly of Floch due to his insistence that Erwin be saved during the Battle of Shiganshina instead of Armin. However, he would later set aside any prior animosity, allowing the two to work together as part of the Yeagerists. Eren would put great trust in Floch, confiding in his genocide plan long before its execution.
 * Yelena - Eren shares Yelena's concern regarding Marley's desire to destroy the Eldians and works along with her to take over the Eldian military. He is willing to hear her opinion, but insists that he is not being controlled and is following his own sense of judgment. Eren seemed to follow Yelena's instructions, but his complicity in her and Zeke's plan would turn out to be ploy, and Yelena's trust in him evaporated as she witnessed the start of the Rumbling.

People killed

 * Grisha Yeager (unintentional, as a Pure Titan)
 * Willy Tybur
 * Zofia
 * Calvi
 * Younger sister of Willy
 * Halil
 * Ramzi
 * Hange Zoë (unintentional)
 * Two unnamed robbers
 * Audience members at the festival hosted in Liberio
 * Numerous residents of Liberio
 * Numerous residents of Marley

Indirectly

 * Bertolt Hoover
 * Udo
 * Lobov (unintentional)
 * Sasha Blouse (unintentional)
 * Porco Galliard
 * Frieda Reiss
 * Dirk Reiss
 * Abel Reiss
 * Florian Reiss
 * Rod's wife
 * Urklyn Reiss
 * Six unnamed Survey Corps members (unintentional)
 * Over a hundred Stohess District citizens (unintentional)
 * Numerous residents of Paradis Island (unintentional)

Failed attempts

 * Bertolt Hoover
 * Mikasa Ackerman (unintentional)
 * Annie Leonhart
 * Reiner Braun
 * Falco Grice
 * Porco Galliard

Trivia

 * Eren ranked second in the First Character Popularity Poll, right after Levi Ackerman.
 * Eren ranked third in the Second Character Popularity Poll.
 * Eren ranked fourth in the Third Character Popularity Poll.
 * Hajime Isayama has said that he does not see Eren and Armin being best friends forever.
 * This proved to be true after Eren declared Armin as being controlled by Bertolt, and through their fight after Eren declared he has always hated Mikasa.
 * Because Eren is an energetic character, Isayama chose to give him black hair so that it would be easier to draw speed lines around him when he is moving.
 * Isayama has stated he paid particular attention to Eren's eyes when designing him, in order to make him stand out from the rest of the cast. He specifically chose to give Eren thin eyebrows instead of thick ones because he felt it would be "articial" to try to use thicker eyebrows to accent Eren's angry personality.
 * Isayama has stated that he has struggled in the past to make Eren feel "alive" when writing and has called the character "a slave to the story [of Attack on Titan]."
 * Because of this, Isayama has stated that he did not expect Eren to be popular with readers and has cited his popularity as being a greater surprise than any other character's.
 * Isayama stated in an interview that due to the fact that he and Eren are "polar opposites," he had a hard time writing for the character until around the fourth volume of the manga. He claimed, however, that he was not truly able to understand Eren's character until he heard 's portrayal of him.
 * Isayama stated in an interview that he based Eren's Titan form off of the Japanese martial artist Yūshin Okami, paraphrasing it to be the "ideal physique of a middleweight mixed martial artist."
 * Isayama has also identified Takanori Gomi's southpaw fighting style as a model used for Eren's Titan and the way it fights.
 * The name "Eren" is of Turkish origin. Its exact meaning and description is "He who progresses/has reached towards divine maturity and sacred wisdom". It can also be interpreted as a "saint" or "holy person." "Eren" could also stand for the German word "Ehre" (plural "Ehren"), which means honor.
 * Isayama has stated that part of the reason he chose the name "Eren" for the character is because it sounds feminine, which would make it easier to remember.
 * Eren's surname, Yeager, is an anglicized form of the German surname "Jäger," meaning "hunter."
 * Isayama said he was skeptical about the importance of bloodlines when coming up with Eren, which is why he made him someone not blessed with natural talent and the polar opposite of a chosen talented protagonist.
 * Eren's name is believed to have come from his father's compatriot, Eren Kruger. He also uses his last name, Kruger, when he pretends to be an injured soldier while infiltrating Marley.
 * When speaking about Titans, Eren had the habit of using -hiki (the counter suffix for small animals) instead of -tai (the counter for large animals), signifying his deep contempt for them.
 * He has the highest Titan kill record by far of all the former graduates of the 104th Training Corps, though he has killed only one Titan in human form with his vertical equipment abilities, and the rest have been killed using his Titan abilities. In human form, the most kills belong to Mikasa.
 * According to Isayama, if the 104th Training Corps had an arm wrestling competition, Eren would be evenly matched with Jean Kirstein.
 * An interview with Isayama's editor in Otomedia's October 2013 issue revealed Isayama originally intended for Eren to have known all along that he was a Titan, but scratched the idea.
 * In the game Age of Gunslingers Online, a special Titan Mode was made as a tribute to the series. It features Eln, an NPC modeled after Eren and voiced by Yuki Kaji. A trailer of this mode can be viewed here. There is also a special skin for the Dual Pistol class available for purchase.
 * Eren ranked first in the Akiba Souken Shingeki no Kyojin online character popularity poll.
 * In a 2013 blog post Isayama revealed that he had selected "Otoko wa Romandaze! Takeda-kun" by as a character song for Eren.

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