The protagonist of the famous anime Attack on Titan, Eren Jeager, was first introduced as a ten-year-old boy ready to fight anyone and anything. His spirit was strong and unwavering, making his seemingly impossible dream possible. Even though he wasn't the best soldier, the passion he had was intoxicating. All of this changes at the end of season three going into season four, where Eren's life is all but gone.

In seasons one to three, Eren maintains an unwavering belief that humanity can be freed from the Titans. No, longer trapped behind the three walls, waiting for their extinction. He's an extremely proactive character prone to confrontation and arguments, but this nature is welcomed in a world filled with dread. Not until Rod Reiss tries to get Historia to devour Eren, fans see a crack in Eren's resolve. Having just been kidnapped by Reiner and Berthold, and now Rod Reiss, Eren begins to believe he can't save humanity after all. During his time chained up in the crystallized cavern, Eren reveals his doubts about his importance to humanity's salvation.

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Too Tough for his Own Good

Attack on Titan Mikasa and Eren held back by Armin

Before all of this, Eren's personality embodied the Attack Titan's mission. His belief was to keep fighting no matter what because if no one fought, freedom couldn't be reached. This mindset caused Eren to get into more fights than necessary, forcing his friends Mikasa and Armin to step in. For the overall dynamic of the trio, the personalities make sense. Armin is the brain, taking the time to think logically before taking action. He might not be the strongest, but they usually pull through with Mikasa and Eren's help. Then there is Mikasa and Eren, Mikasa might not have the drive, but she has the skills needed to get the job done. Leaving all the passion and drive with Eren's character.

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This decision between personality traits makes the relationship between the three work, except what happens when Eren, the glue that keeps the trio together, starts to break. Throughout the entire show, Armin and Mikasa fight to save Eren, failing more times than they would like, and it's during these times, Eren's character starts to change. He is no longer fighting mindless titans or street thugs; he has to face Annie, Riener, Berthold, his comrades. This leaves his clearly defined world shaken; how can you fight your friends? Then there is also the problem of losing comrades.

Eren had put his faith in Levi's squad to protect him from Annie, and what did this lead to? The entire group was killed because he thought they could keep him safe. Of course, the group wasn't prepared for what the Female Titan could do, but these events, combined with what happened in Rod Reiss's cave, changed Eren. He didn't believe in himself or the others. He'd wanted to be devoured, hoping Historia could change things, but she refused. As a last-ditch effort to save everyone from the cave collapsing, Eren transforms into his Titan form, using Titan spinal fluid that says armor.

What Does This Mean for Eren's Character?

Attack on Titan Injured Eren Jaeger

The previous events leading to Eren reaching his father's basement made Eren realize that he couldn't always rely on his friends. They could be traitors, or worse, they could end up dying on his behalf. This is before Eren gains the memories of Grisha's time in Marley, so Eren believed the only threats were the Titans and the Titan shifters. With the new memories, Eren finally understands the real dangers in the world. Fighting wouldn't stop after the Pure Titans were destroyed because Marley would continue to attack them until they were all dead.

Eren can no longer enjoy the world; even after reaching the ocean, his thoughts were on Marley and how they were just beyond the sea. Instead of fighting for freedom, it would seem Eren is fighting for his friends' lives. The distinction between his own life and his friends' lives is made because of the distance he sets. During the first half of season four, Eren doesn't tell the others that he plans to infiltrate Marley and take the War Hammer Titan until he is in Marley. He refuses to negotiate or change his plans no matter what, even killing innocent people.

It would appear that Eren has no other concern than stopping Marley. The best way to achieve this is on his own, or at least away from Armin and Mikasa, because if he does trust them with this mission, they might die. Like Levi's group during season one, all killed trying to protect Eren. Instead, by gaining the power of the War Hammer Titan and going along with Zeke's plan, Eren can keep them safe, even if it means sacrificing himself. Eren's no longer the naive child with the dream to be free. As an adult, Eren wants to keep his childhood friends safe, which has cost him his humanity.

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