WARNING: The following contains spoilers for Attack on Titan Season 4, now streaming on Crunchyroll, Funimation, Hulu, and Amazon Prime.

The fourth season of Attack on Titan changed practically everything about this story -- the stakes, the power players, and the distinction between friend and foe. The series began as a desperate defensive war against the encroaching Titans, but all that is over now. The Titans are the symbolic power of the Eldian people, and the twists have kept on coming.

Throughout Season 4's first twelve episodes, Attack on Titan has reinvented itself at a breakneck pace as shocking developments rocked the world and new revelations piled up. Which particular twists in this season have had the biggest impact on the lore?

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When Eren Raided Liberio During Willy Tybur's Speech

Eren Killing Willy Tybur Cropped

Early in Season 4, Gabi Braun and her friends arrived at their home city of Liberio. Not long after, Willy Tybur gave a rousing speech to the assembled leaders and ambassadors from diverse nations while explaining the backstory of Helos and King Tybur. Just as Willy declared that Marley would crush Paradis Island once and for all, Eren Yeager took the initiative with his Attack Titan, crashing the party in a big way.

Eren went on a rampage with Mikasa, Armin, Sasha Braus and others backing him up during this heavy raid. Willy Tybur lost his life as Eren and his fellows defeated the War Hammer Titan to secure their victory. However, the Eldians suffered a certain casualty on their way out: Sasha, who died at the hands of Gabi. Mikasa and Armin were grief-stricken, but oddly, Eren was not. He cared only for victory.

Eren Becoming An Eldian Extremist & Inspiring A Coup

Eren And The Yeagerists

When Eren returned home to Paradis Island with his fellows, he wasn't content to throw a victory party and get complacent. He was already planning his next move, and by now, his half-brother Zeke was enabling (or manipulating) him. Eren gave himself a pep talk before a mirror with a reminder to "fight, fight," and that's exactly what he did. He soon became a rogue element, threatening anyone who got in his way with his three Titan Shifter powers, which now included the War Hammer Titan. He was rapidly collecting power, both as a Titan Shifter and a rebel leader.

Eren inspired an entire cult of so-called Yeagerists, who defied the military chain of command and pressed for war against Marley. Only decisive action would win the day, they claimed, and Dot Pyxis and his officers were too slow and cautious to bring true freedom to the Eldian people. Before long, Paradis Island was split into two camps, and Mikasa and Armin weren't exactly on the Yeager side.

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Zeke Using His Spinal Fluid To Forcibly Create Pure Titans

wine attack on titan

When Zeke and some other Marleyans arrived on Paradis Island, they brought with them the secrets of Marleyan seafood cooking (via Niccolo) and more than a little Marleyan wine, which was a real treat. Some soldiers, and nearly all officers, treated themselves to this wine, unaware of its special ingredient. Zeke had placed his Beast Titan spinal fluid in it, priming each drinker to become a pure Titan if Zeke were to perform a shout.

Zeke had tested his spinal fluid a few years earlier in Ragako Village, shouting to transform all the villagers -- including Connie's mother. Now, Zeke can escape any soldier by transforming them and can hold all Paradis Island officers hostage. By the time Mikasa and the others pieced this together, it was too late. The gun was already cocked, and Zeke controlled the trigger.

The Possibility That Memories Can Influence Titan Shifters

Eren looking over his shoulder in Attack on Titan Season 4

Later in the season, Eren and Armin faced each other as fellow Titan Shifters, and Eren brought up the topic of Armin's frequent visits to the petrified Female Titan wielder Annie Leonhart. Eren knew that Bertolt Hoover once used the Colossal Titan, and he posited this possibility: what if Bertolt, who had been Annie's friend, was influencing his successor Armin?

Through the Colossal Titan, Bertolt's memories might be reshaping Armin's mind and emotions, driving him to visit Annie and even consult her non-responsive body during moments of hardship. But this goes both ways. Suppose the Titan Shifter powers inside Eren were controlling him? He's got Grisha Yeager, Frieda Reiss and Lara Tybur in there, and they might be fighting over whether Eren should continue his war on Marley or not. This may be why Eren told himself "fight, fight" to ward off the naysayers inside him. Lara Tybur, at least, must disapprove of his plans.

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The Revelation Of Zeke's Euthanasia Plan

Zeke in Beast Titan

Zeke Yeager first appeared as the Beast Titan, the next great challenge after Annie's Female Titan was defeated. But Zeke wasn't just a brute warrior for Marley. He deeply sympathized with all suffering people. As a boy he realized that all suffering in the world was due to the Subjects of Ymir having the power of Titans, and even the Eldians themselves suffered in some ways. It's time to end the suffering by taking Eldia out of the equation entirely.

Zeke's pro-Eldia plan appeared to be a nationalist movement at first. But in reality, Zeke intends to not only defend Paradis Island from its enemies, but also sterilize its people with the Founding Titan's power to allow Eldians to gently but surely disappear from the world. Zeke doesn't want anyone to invade Paradis Island, nor does he want the Eldian Empire of old to return. He'd rather lay his own race gently to rest and usher in peace in a Titan-free world.

When The Marleyan Forces Arrived At Paradis

eren yeager attack on titan

In the last episode of Attack on Titan's fourth season's first half, Pieck Finger (the Cart Titan) intervened when Gabi Braun and Eren clashed. Pieck claimed she was now on Eren's side, since Marley couldn't offer a true future for Eldians like her and Gabi. A horrified Gabi was chained to Pieck as the three of them proceeded to the building's roof, so Pieck could point out the true enemy.

On that roof, under the afternoon sun, Pieck indeed pointed at the enemy: Eren himself. At the same time, Porco's Jaw Titan emerged from the building and threw Eren off his feet as a Marleyan aerial fleet arrived to lay siege to Paradis Island, with Reiner Braun standing beside officer Magath in one of the zeppelins. Eren wanted war with Marley, but now, the war has come to him. Can Eren defend his island home with three Titans on a moment's notice? Season 4's second half is bound to start on a gripping note.

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