First Battle

is the 4th and final chapter of the 1st volume and the 4th chapter overall of the Attack on Titan manga, written and illustrated by Hajime Isayama.
In Isayama's original vision, the main events of this chapter, with some alterations, were supposed to be shown in the second chapter of the series.
== Overview ==
Eren immediately targets the Colossus Titan but is unsuccessful as it disappears in the steam. Chaos erupts at headquarters, where newly graduated trainees are forced into battle due to the shortage of soldiers. Mikasa is separated from Eren as she is assigned to the elite squad in the rear guard to protect civilians. A brief flashback to the trainees' classroom reveals the little information humanity has obtained so far on the Titans. Afterward, Eren and his group move out as the middle guard, foolishly confident. Things fall apart as they are eaten one by one. Armin, the last one alive and uninjured, is paralyzed in horror until he, too, is grabbed by a Titan. Driven by their dream to leave the Walls one day, Eren musters the strength to save him just in time, sacrificing himself in the process.
== Summary ==
The Colossus Titan, which has not been seen in five years, continues its assault on Wall Rose. Using his vertical maneuvering equipment, Eren alone climbs the Titan's arm. Along the way, he realizes that the Titan is not attacking at random, but is intentionally aiming for the canons and the vulnerable district gate. He deduces that, unlike any other Titan, it may possess intelligence.
Knowing that this is a rare chance to eliminate the only Titan capable of destroying the Walls, Eren does not hesitate to target its weak spot on the back of its neck. However, he is temporarily disoriented when the Colossus Titan suddenly emits a burning gas from its body. When the smoke clears, the Titan has already disappeared into thin air, leaving nothing but smoke and two large footprints―just as it had five years ago.
A panicked conversation between Eren and his comrades, who were paralyzed in fear the entire time, is cut short when a member of the Garrison vanguard shows up and tells the trainees that the Colossus Titan strategy has started. He then orders those who made physical contact with the Colossus Titan to report to headquarters. With the Survey Corps out on exploration duty, the Garrison soldiers are the only military presence available to repair the Wall and prepare an ambush. The city is once again in a panic. The shortage of soldiers puts the newly graduated trainees in the sink or swim position of filling in the gaps.
Mikasa, still at headquarters, is among a crowd of frantic trainees and overhears Franz comforting Hannah. She finds Eren and Armin, who analyzes the dire situation in a panic; there is an eight-meter high hole in the Wall, and the rock meant to fill it in has not even been excavated yet. With the hole there, the city will be abandoned and Wall Rose will be vulnerable. Briefly letting the fear get the better of him, Armin worries that the Titans could eradicate humanity at any time. Eren calms him and he is able to gather himself and continue his work.
The trainees are given their instructions and divided into three groups: the front guard will be assigned to the Garrison, the middle guard will work for the training corp, and the rear guard will serve under the Garrison's elite. The trainees are made aware of their commitment; fleeing in front of the enemy will be met with capital punishment and they are to give their lives if necessary. After they are dismissed, Jean despairs the fact that, had the attack happened just one day later, he would already be safely in the inner district. Mikasa tells Eren to find her if things get bad in battle, determined to protect him. However, she is then assigned to the rear guard due to her superior physical abilities, making the request to Eren difficult. Angry, Eren tells Mikasa to stop trying to impose her own rules during a time of crisis; she then apologizes for getting carried away. Distraught, Mikasa has one more request for Eren: do not get killed.
Eren thinks back to the teachings in the trainee classrooms and reflects on how little is known about the Titans. The meager information they have is all thanks to the Survey Corps. They know that the Titans lack sexual organs, leaving their modes of reproduction unknown. They show no interest in eating any creature other than humans but have lived largely devoid of humans for 100 years, suggesting it is not for nourishment. What stands out even more is their vitality and ability to heal from seemingly devastating wounds. The only spot they can not regenerate from is at the nape of the neck; a blow which is best delivered using vertical maneuvering equipment.
thumb|left|200px|Mina, Mylius, and Nac are killed
Now on top of a roof in their assigned position, Eren and Armin, along with other trainees, prepare for the task ahead. Eren, encouraging Armin, says that they should be able to rise through the ranks of the Survey Corps quickly if they start practicing now. Not wanting to be outperformed like the previous encounter, Thomas and the other trainees suggest a Titan hunting contest. Confidence is lost immediately when they run into Titans who have come through the hole in the Wall. It seems that the front guard already have more than they can handle. As the group moves along the rooftops, a Titan lunges in for an attack. They scatter but unfortunately, Thomas is caught in a Titan's mouth. Eren watches in horror as his teammate gets swallowed whole. In a rage, he recklessly rushes off to kill the Titan with its back turned, not noticing another one below him. It jumps up and bites off Eren's leg below the knee. Watching Eren bleeding and stranded on a nearby rooftop, Armin freezes in shock.
The remainder of the team unsuccessfully attempted to fight back. Mina's vertical equipment wire gets caught and she is knocked unconscious against a building, while Mylius and Nac are devoured. Still, in shock, Armin watches as his teammates are eaten or torn apart. A nearby Titan takes advantage of the trauma and grabs Armin, who is paralyzed and does not put up a fight. Bleeding and barely conscious, Eren sees his friend in need and briefly recalls a childhood memory in which Armin excitedly shows him a book belonging to his grandfather detailing the outside world. Empowered by Armin's dream of leaving the Walls one day, he picks himself up and rushes to the aid of his friend. Inside the mouth of the Titan, Eren grabs Armin before he is swallowed and throws him outside. With Armin now safe, Eren attempts to escape, refusing to accept death with so much more to live for. As they reach for each other, the Titan bites down, cutting off Eren's left arm. Armin watches in terror as the Titan swallows Eren.
In the distance, Mikasa is seen staring in the direction of her friends with an uneasy feeling.
== Current Publicly Available Information ==
=== A Basic Overview of the Vertical Maneuvering Devices ===
The operating device is run by a black box (technical specs, maintenance, and improvement of these specs are secret).
(The vertical maneuvering device)
* Steel wire is stored in the operative section
* Two axes spin independently
* Main tap connected to cylinder
* Connected to the operating device
* Connected to belt
* Steel wire to pierce Titans, etc.
(Parts of the fan)
The part that blows gas towards the fan and the emission are black boxes (technical specs, maintenance, and improvement of these specs are secret).
Gas is blown directly at the fan to make it spin.
The emission system is shaped like a shuttlecock so it doesn't interfere with the gas coming in through the intake port.
Gas pressure is adjusted to manage the output.
The gas is compressed into the cylinder, then injected into the tube.
Author's note: Thanks to my scientist friend who helped me come up with this!
== Characters in order of appearance ==
== Navigation ==
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