Attack on Titan is one of the most popular anime series in the 2010s. The show first aired in 2013, with its Final Season Part 3 releasing soon in 2023.
It will follow Eren’s plan of eliminating the rest of the world aside from his home, Paradis Island, through Rumbling. It brought about a sense of shock among fans. After all, in the earlier seasons, Eren is a ‘hero’ who wanted to protect his friends and comrades. He placed value on human lives – to the point of becoming reckless on many occasions. Jean called him out as a ‘suicidal maniac’ because of this.
Yet, Eren’s dark turn is not out of the blue. Ever since he discovered that there are more human civilizations beyond the walls, he became disillusioned. There are notable scenes indicating his change as seen below.
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The Beach Scene
In the last episode of Season 3 Part 2, he was the only person who did not seem to enjoy seeing the beach. He instead looked somber, and said, “If we kill all our enemies out there, will we finally be free?“

Eren’s Surprise Attack on Marley
In Final Season Part 1, Eren’s change became more clear even in the beginning. He started planning on his own. He did not consult his superiors, Captain Levi and Commander Hange; and even his best friend Armin.
He executed a surprise attack against the Marleyans that resulted in many casualties. Mikasa even noticed this and was forlorn when she told Eren about it.

Eren Hurting Mikasa
He also downright broke Mikasa’s heart by saying he has always hated her. It resulted in the usually composed Armin losing his temper and punching Eren. This scene alone meant that Eren was intent on pursuing his own goals, to the point of severing his close relationships.

Eren Cutting Ties with Survey Corps
The season concluded with Eren deflecting from Survey Corps with the help of the Yeagerists and Yelena. They aimed to dismantle the military powers of Paradis – to cut any potential threats. The members of the Garrison and the Military Police have been given wine with Zeke’s Titan spinal fluid in it. The final nail in the coffin was killing off Military Police Commander Darius Zackly.
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Eren Manipulating His Dad
In Final Season Part 2, it t turns out he was the one who manipulated his father, Grisha, to kill all the members of the Reiss family. Grisha seemed so shaken and hesitant, while Eren was angry and firm.

Eren’s Plan
This culminates to his ultimate plan. Once he managed to gain the favor of Founder Ymir, he telepathically communicated his plan to the Subjects of Ymir. He reawakened the hordes of Colossal Titans within the walls to trample the rest of the world.

So, is Eren really evil?
With these actions in mind, it is easy to label Eren as ‘evil’ because of his indifference to human lives. But is he ‘evil’ for the sake of being evil? No, because if there’s one thing Attack on Titan taught us, all the characters have their reasons why they do things. Reiner, Bertholdt, and Annie have reasons why they destroyed the walls of Shiganshina District.

The scene between Reiner and Eren is very significant. It highlights how both Reiner and Eren had a strong resolve to protect the home they grew up in. They became soldiers who trained to eliminate outside threats that served as the reasons for their suffering.

As such, we can conclude that Eren pushing through with his plan is not without reason. Paying attention to his telepathic message to the Subjects of Ymir:
…My goal is to protect the people of Paradis, the place I was born and raised. However, the world wishes for the annihilation of the people of Paradis, not just this island, but all of the Subjects of Ymir… I reject that wish. The Wall Titans shall trample all surface of the land outside this island. Until all lives existed there have been exterminated from this world.
Eren Yeager

The hatred directed towards Eren’s race: the Subjects of Ymir – especially those who live in his home, Paradis Island, motivated his plan. One can understand where he comes from, and his intentions can even be considered noble. His actions deviate from those noble intentions, however.
Eren’s actions and morality are debatable. Fans are still discussing it on various online – specifically on Reddit and Quora. In other words, Eren has evolved from the typical shounen protagonist to a complex anti-hero. His morality lies in a gray area that makes him more interesting to watch.
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