Eren Jaeger (エレン・イェーガー Eren Yēgā?) was a former member of the Scout Regiment and the main protagonist of Attack on Titan. He was the only son of Grisha and Carla Jaeger, the younger paternal half brother of Zeke Jaeger,[25] and the last holder of the Attack Titan, Founding Titan,[26] and the War Hammer Titan.[10]

Eren was born and raised in Shiganshina District, which is located on the southern edge of Wall Maria. He lived there until the year 845, when the Colossal and Armored Titans breached the Wall, allowing a flood of Titans to invade and destroy the city. During the incident, Eren witnessed his mother being murdered and eaten by a smiling Titan.[25] This event aroused in Eren an intense hatred towards the Titans, and he swore to wipe all of them off the face of the earth.[27]

Soon afterward, his father, Grisha Jaeger, 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 injection.[28]

Two years later, Eren along with his two friends Mikasa Ackermann and Armin Arlelt joined the 104th Cadet Corps.[29] The three successfully graduated, with Eren ranking as the 5th best cadet, and they joined the Scout Regiment following the struggle for Trost.[30]

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 sea.[31]

Eren possessed the power of three Titans. From his father, Eren inherited the Attack and Founding Titan. After eating Lara Tybur during the Raid on Liberio, he gained the War Hammer Titan as well.[10]

Eren was a young man of average height and muscular build. He had a fairly long, yet rounded face, and sizable, expressive, teal-green eyes. His eyebrows were sparse and often furrowed, making him seem troubled or annoyed. Eren's hair was short and dark brown, with his bangs falling naturally into a middle-parted, curtain-type style. His complexion also seemed somewhat tan. After his training and during his time as a soldier, he became very physically fit and muscular.

Eren was first seen wearing regular townsfolk attire, which consisted of brown trousers, a green shirt with string tassels at the collar, a maroon coat, and simple brown shoes. A few years before the fall of Wall Maria, he also wore a red scarf, which he gave to Mikasa the day they met. Eren was often seen in the typical Scout Regiment uniform when training. His casual attire consisted of a long, beige shirt (identical to that which he wore on his first appearance) that was worn with a maroon sash about his waist, brown trousers, and brown shoes. He always kept the key that was given to him by his father around his neck on a string.[27]

By the time Eren infiltrated Marley in the year 854, he had grown visibly taller, and his hair had grown down to shoulder length. He had a slight mustache and goatee, as well as bandages that covered his forehead and left eye. To maintain his cover, he wore 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.[24] Later when he was imprisoned for the second time following his infiltration in Marley, he tied his shoulder length hair into a man-bun style which shows two of his small fringes in each sides and being cleanly shaved.

Attack Titan form

As a Titan, Eren's appearance changed quite drastically. Along with a massive increase in height (to 15 m), his hair grew long enough to graze his shoulders, with his tongue and ears becoming elongated. His facial features also underwent a transformation. Along with a prominent, hooked nose, his eyes were deeply sunken within their sockets, and his mouth took on an unusual, jagged shape that is unsuited for intelligible speech, though he was capable of howling and roaring when expressing his exhaustion and anger. He also lacked lips and flesh on his cheeks, exposing all his teeth. A third transparent eyelid could also be seen on both of his eyes.

Similar to other intelligent Titans, Eren's Titan form was well-proportioned and physically fit, sporting a well-defined, lean, muscular appearance in lieu of the more common pot-bellied or emaciated appearance of regular Titans.

In its burning state seen when it lifted the boulder in Trost and when it fought the Female Titan, the Titan was deep black, had burning marks all over his Titan, and had blue eyes and sharp teeth instead of straight teeth.

Founding Titan form

Eren's Founding Titan, dubbed Doomsday Titan[32][11], was drastically different than Ymir Fritz's Founding Titan, or any other Titan for that matter. It towered over the horde of Wall Titans. What appeared to be the torso was devoid of flesh, resembling an enormous ribcage. The knobs of the backbone and ribs were grossly lengthened; the ribs reaching the ground while the arch of the spine extend far into the sky. The pelvis and legs were greatly undersized however, seemingly useless. Despite this, they were still taller than any Wall Titan.

The upper body seemed proportional with the legs, meaning that they were dwarfed by the ribcage. The head was the only part of the body with much flesh, although it was significantly deformed: both the ears and hair were greatly elongated; the cheeks were missing, exposing the molars; and the bottom jaw was nearly bare, only the lips and chin being present. Like a puppet, the upper body was suspended by sinew, supported by the vertebral knobs like a suspension bridge.

The Titan walked with its "ribcage", undulating the ribs like a millipede's legs. It was fast enough to keep within view of the rumbling.[33]

Pure Titan form

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