WARNING: The following contains spoilers for Season 4, Episode 14 of Attack on Titan, "Savagery," now streaming on Crunchyroll, Funimation, Hulu and Amazon Prime.
Eren Yeager certainly has a complex relationship with the existence of Titans. For years, he hated them with every fiber of his being, since they ate his mother Carla and overran his hometown, Shiganshina. Years later, he discovered that Titans are his Eldian kin, and they are tools to be used, not monsters to be feared. But now, Eren might be in a submissive position once again.
The Titans once used fear to control Eren's life, then Eren turned the tables with his Attack Titan and the Founding Titan. He and his half-brother Zeke are launching a pro-Eldia movement, and just when Eren's mission is reaching a critical phase, a new factor emerges in Episode 14 of Season 4: Titan Shifter memories. This may threaten to derail Eren's plans.
How People Can Be Unwittingly Influenced As Shifters
In the world of Attack on Titan, many parties have found ways to control other people or even entire nations. The Marley empire inundates its Eldian population with cruel propaganda, while the Reiss family forced peace upon Paradis Island with the memory-wipe effects of the Founding Titan (until Historia Reiss put a stop to that). Then there's the matter of the Ackermans, designed to serve and protect the royal family whether they like it or not. And that's not all. Inheriting a Titan Shifter comes with serious baggage, such as the need to use that power responsibly and the 13-year time limit imposed upon the user. And there's still more. When someone inherits a Titan Shifter, Eren reminds Armin in "Savagery" that they will also inherit the memories of previous users, and those memories might influence the current user with the previous user's desires and emotions.
How has this factored into the story so far? As of now, Armin Arlert has the Colossal Titan, thanks to Levi choosing him over Erwin Smith with that Titan serum. Armin thinks that he is in total control of his powers, but Eren thinks he might not be. After all, he's been visiting the inert body of Annie Leonheart for quite some time, as though consulting her or treating her like a sounding board. Armin and Annie weren't exactly the best of friends, but Annie and Bertolt, the Colossal Titan's previous wielder, certainly had been allies. Perhaps Armin's newfound fondness for Annie is the Bertolt inside him taking control, which Eren is quick to point out.
Armin denies it, but the evidence is there, and Eren wonders if this may compromise Armin's ability to aid them against the Marley Empire. What if Armin tries to sabotage Eren, acting on behalf of Bertolt's memories, which prioritize Annie and the Marley Empire over everything? Eren would rather nip this in the bud before it becomes a serious problem.
What If Eren Is Being Controlled, Too?
During this tense tabletop conversation, Eren insists that he is truly free of everything: free from Paradis Island's leaders, free from the chain of command, and free from all fear and doubts. Eren truly believes that but he may be wrong, and Armin says as much. Armin is concerned that Zeke Yeager is just using Eren and exploiting their familial bond and their father's dreams, and Eren is a bigger tool than anyone. And there might be some puppetmasters inside Eren, too.
Previous episodes hinted at an internal struggle when Eren faced his reflection, breathed hard and urged himself to "Fight. Fight." Under ordinary circumstances, would he really need a pep talk like this? Probably not, or at least, not with such tension. Hange Zoe found this scene rather odd, and now, in light of the Titan Shifter memory concept, it's possible that Eren is fighting off the memories of Frieda Reiss, who once commanded the Founding Titan, and Lara Tybur, who once wielded the War Hammer Titan. Frieda, like the other Reisses, had wanted to maintain the status quo and maintain the Reiss family's dominance of Paradis Island. Lara Tybur had been a loyal subject of Marley, and she would not want Eren to invade and destroy her home.
These women may be tugging at Eren's mind, fighting to turn him away from his plans of Eldia's restoration and Marley's destruction, and inside, Eren may have the memories of his father, Grisha, backing him up. If so, it's a 2-vs-2 battle in Eren's head, and anyone would have to remind themselves "Fight. Fight," to keep their eyes on the mission. Eren's struggle is both external and internal, and it probably won't be resolved anytime soon.