Eren Yeager

Eren is the main protagonist of the series. He is from Shiganshina District, a town of the outer most wall, Maria. His closest friends Mikasa and Armin have both joined the Scouting Legion with him after having their town annihilated by the Titans. He holds a personal vendetta against all titans and his goal is to annihilate them from the earth.

Personality
Eren can be seen as violent and impulsive. He has the desire to kill and destroy all Titans because of his mother's death. He cares for his comrades and even risked his life just to save them. Eren is also very strong about the way he feels. In chapter 1 he was was so intent on joining the Scouting Legion he shouted at his mother and referred to the people in the village as "silly".

As a human
Eren has a fairly long face. His hair reaches the bottom of his neck and falls infront of his forehead. His hair parts in the middle of his head giving him a "curtain" style. He wears a plain white top with his with string acting as buttons. He wears black trousers and black shoes with this.

As a Titan
As a titan Eren's appearance completely changes. He has no clothes and his height increases massively. His hair grows longer and his eyes become long and this as opposed to his normal eyes which are short and wide. His tongue becomes pointed and his teeth grown and become dagger shaped which makes many think this symbolizes a demon.

Year 844
When Eren was a child, he saved Mikasa from being killed when visiting her home with his father. Three men, which were the killers of her parents, were in her house. Killing two of them, he was caught off guard by the third who proceeded to strangle him. With superhuman strength, Mikasa leapt forward at the man after realizing that it is a "live or die" life they are living. As Eren's father finds them surprisingly safe and unharmed, Eren gave Mikasa the sentimental scarf she always wears, and declared her a part of his family.

Year 845
With the invasion of Wall Maria after the Colossal Titan makes a path, Eren discovered the horrors of the life he is living that sets the motion for his future. Seeing the destruction of his town, mindless titans slaughtering humans and his own mother being eaten alive as he was helpless to save her, Eren remarks that the life humans live is controlled entirely at the mercy of the titans and humans are nothing more than cattle. Being dragged away by a local Stationary Guard, Hannes, Eren swears to kill every single titan in existence with tears of frustration and hatred.

Year 845 to current
After the fall of Wall Maria, Eren, Mikasa and Armin briefly stayed in the “landfill” working on a farm before reaching the proper age to enroll in the military. Here they spent approximately four years in training, Eren placed 5th in his class upon graduation.

Introduction Arc
Upon graduation, before Eren is able to formally apply for a position in the Scouting Legion, the Colossal Titan appeared the same as it did the day of the fall of wall Maria. Eren attempts to destroy it, but it vanishes in a puff of smoke after having broken the gate open.

In response to the crisis, the new recruits are scrambled and split into specific teams in charge of spreading to and defending different parts of the city. Eren is grouped with Armin. Upon seeing his comrades killed, Eren lept into battle after a Titan, only to have his leg bitten off below the knee, incapacitating him. The rest of his group attacks and dies as a result. Just as Armin is about to get eaten, Eren manages to pull his friend out of the bearded Titan's mouth, effectively switching places with him. Eren is swallowed, his left arm being severed as the titan shut its mouth.

Transformation Arc
It is later revealed that in the stomach of the bearded Titan Eren’s desperation and drive to exterminate all Titans triggered his first transformation into a Titan, bursting from the bearded Titan and proceeding to wreak havoc on all the Titans he could get his hands on. In the process he unawaredly saves the mourning Mikasa’s life and is baited by a team of his classmates to help fend off a percussion of Titans from a storage headquarters for the compressed gas used to power their 3D movement gear.

As the Titans seem to overwhelm him and Mikasa’s group is about to intervene, a certain Titan that killed one of Eren’s team members appears and Eren’s rage powers him to throw off the percussion and destroy the Titan. As soon as the massacre is over, Eren falls to the ground and his human form emerges from the back of his Titain form’s neck (with both lost limbs back) to the shock of all the onlookers. He is retrieved by an overwhelmed Mikasa.

Upon his awakening, Eren seems to only have a faint dream-like memory of his time as a Titan and finds himself cornered by the military with only Misaka and Armin as his support. The military intends to kill Eren, thinking him an enemy. A cannon is fired at the three of them and Eren grabs onto his two friends and bites his own hand, wounding himself and partially transforming into a Titan, blocking the cannon ball before emerging form the skeleton. Eren allows Armin to try and talk them out of their tight spot with limited success until Commander Dot Pixis intervenes.

A plan is made for Eren to use his Titan form to moves a huge bolder they had planned to use to stopper the gate if such and attack as this occurred, but were unable to move. Eren is assigned to a team including Misaka to defend him while he carries the boulder. Upon his transformation to execute the plan, though, he attacks Misaka, who tries to communicate with him to snap out of it, unsuccessfully. Eren ends up wounding himself and his body fails to regenerate, the mission is declared a failure. Despite this, the leader of the group, with some non-verbal convincing by Misaka, decides they must stay and guard Eren.

Armin arrives on the scene and convinces Misaka to go help fend off the Titans while he tries to get through to Eren. Eventually he is able to do so, and Eren moves the stone and is able to stopper the hole in the wall at the sacrifice of the rest of the team members (with the exception of Rico, Armin and Misaka). They are saved from the desperate situation after Eren’s transformation back to human by Rivaille.

Eren again woke up this time in a dungeon prison cell chained. Rivaille was there and upon hearing his motive to kill Titans says he’ll accept him on the team. Eren was left there for a time before he was escorted by Scouting Legion members to the court room where he was tried with one side calling for his decision and execution and the opposing side, the Scouting Legion, arguing to use his power to their advantage in scouting missions. After and outburst by Eren, Rivaille beats him accrediting his dominance over Eren’s  threat and it is decided his fate will be decided after a “test” mission with the Scouting Legion.

The Female Titan Arc
Eren, along with some of his old classmates, which also joined the Scouting Legion, train for a month, learning long distance communication formation, before they had to depart outside wall Rose to the ruin in the region once protected by wall Maria. Eren along with most of the group were not told the goal of the operation but were simply expected to follow orders. Eventually, a deviant “intelligent” titan known as the “Female Titan” caught up with Eren’s team and pursued them into a huge forest. Upon it’s closer approach and the death of some comrades from behind as Eren and his team simply keep running, Eren is tempted to use his Titan power and save his comrades and fight the Female Titan. Rivaille allows this choice, but Eren eventually decides to trust in his team, scarifying the last remaining member of the rear guard.

The Female Titan, suspected to be the same as Eren and merely a “human in titan skin,” nearly captured Eren before being ambushed and captured herself. Eren and the rest of his team excluding Rivaille ride out of the forest firm in the belief that the titan was captured and her human self apprehended. This is proved false as the unidentifiable human form of the Female Titan kills one of the team members before re-transforming into a titan. The remaining three team members tell Eren to go on while they kill the Female Titan. Eren wishes to stay and fight with them, but again, is convinced otherwise and retreats. The three are promptly slaughtered and a regretful Eren transformed into a Titan and engaged the Female Titan.



He ultimately loses the fight and his human self was captured by the Female Titan. Mikasa arrived on the scene in time to observe this and pursued to retrieve him, closely followed by Rivaille. The two teamed up to retrieve Eren, leaving the Female Titan alive and whilst they departed back to wall Rose, the mission failed and many soldiers lost. Eren is shocked when Annie Leonhardt smiled the same way the Female Titan did when she unhooded Armin. Eren is later realises that Annie is the female titan. When he tried to go into Titan form by injuring himself, he couldn't do it because of his shock and his mind was clouded. Going back to a meeting room, Eren apologized to Rivaille for disobeying orders to fight off the Female Titan. If he hadn't done so, they wouldn't gotten in the predicament they're in. When Mikasa and Armin prepare themselves to take on Annie by themselves, Eren eventually overcame his shock and transformed into his titan form and helps capturing her.

Breach Arc
When Wall Rose is supposedly breached, Eren is one of the teams in the area. He was last seen on his way to Castle Utgard under squad leader Hanji Zoe in order to use it as surveillance building. Eren and the rest of the the Scouts arrive just in time to save Reiner and co, Eren kills a 7m type female titan and celebrates his first kill as a Scout. On their way back home, Reiner starts acting weird around Eren and Eren starts to panic. It is then that Mikasa realizes who Reiner and Berthold are and proceeds to try and kill them. Reiner transforms into the Armored Titan and kidnaps Eren. Eren calls Reiner "A fucking traitor" and shifts into his Titan form. He and Reiner then engage in battle.

Physical Abilities
Originally, Eren's only noteworthy trait, was his natural physical strength. As he grew and joined the 104th squad, he trained extensively in hand-to-hand combat, scoring top marks in this class, being second only to Misaka and Annie. His skill includes use of punches, throws and body locks. However these skills would aid him in Titan combat.

3D maneuver gear
At first, it is shown that Eren is not very skilled with the gear, he tried and tried countless times but kept tipping and smacking his head on the floor. People mocked him for this. Eren pleaded for help from everyone but the only advice they could give Eren was that he needed to clear his mind and focus. On his last attempt Eren did just that and stayed upright for a short period of time before tipping over and hitting his head. The commander told Conny Springer to swap equipment with Eren and for Eren to try again. Eren did so and balanced with ease. Commander then told Eren that his equipment was damaged and that it was a miracle that he managed to stay up right at all. He isn't shown using the gear much, but was able to hold his own with the Colossal Titan for a short period of time until the titan disappeared. He was eventually able to slowly develop a respectable amount of skill with the use of the gear, even being capable of killing a titan on own not too long after joining the Scouting Corps.

Titan Shifting
After being swallowed by a titan, Eren was able to turn into a titan. He is much stronger than the average titan, and is able to beat down a whole group of titans quickly. In this form, he is a 15m titan, with shoulder-length black hair, pointy ears, and a huge mouth. Because of his intelligence, something regular titans don't have, he is able to out maneuver the others and quickly beat them down. While initially, having little-to-no control over his actions, he managed to overcome this with extensive use of the transformations. His Titan form, combined with his growing experience and his hand-to-hand combat skills allowed him to overcome and nearly kill the Armored Titan.

His transformations are triggered through causing physical harm onto himself while having a clear goal in mind. He can also trigger partial manifestations.

Trivia

 * Eren-Chara_Design.png is known for fighting with local bullies.
 * Eren's last name, Jaeger, is similar to the German and Scandinavian word jäger, which means hunter. Given the starting lyrics in the OP ("Sie sind das Essen und wir sind die Jäger!" lit. "They are the food and We are the hunters!"), this suggests that the setting might be based on Germany.
 * Hajime Isayama stated in a 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."