WARNING: The following contains spoilers for Attack on Titan Season 4, Episode 21 "From You, 2000 Years Ago", now streaming on Crunchyroll, Funimation and Hulu.
Attack on Titan has long since proved to be a master in foreshadowing, consistently sprinkling in subtle -- and not-so-subtle -- clues throughout the story. These hints set up mind-blowing plot points and hold the key to solving intricate mysteries. And in the final season, fans can finally see it all coming to fruition.
Eren Yaeger is far from being the hot-tempered teen audiences had come to know him as; he is now a cold and calculating character, leaving many to name him as both Attack on Titan's protagonist and antagonist. This older version of Eren has been playing mind games with the other characters for quite some time to keep his real goal under wraps. That is, until Episode 21 finally reveals his sinister plan: exterminate all of humanity, save for the Eldians. While it's a shocking and harrowing goal, Eren's true genocidal plan was actually teased back in Season 3.
The Underground Caverns in Attack on Titan Season 3
In Season 3, Episode 5, Eren is taken to the underground caverns beneath the chapel to be sacrificed to Historia Reiss, but it isn't until Episode 6 that Eren remarks how this all looks familiar -- like he'd been to these caverns before. Since all titan shifters inherit the memories of previous shifters, at first glance, this is because he is connected to the Founding Titan's memories -- many the previous inheritors have been to the underground caverns before. However, come Season 4, new revelations suggest that it could also be because Eren is connected to the past and future.
In "Memories of the Future," Eren and Zeke take a trip through their father, Grisha Jaeger's, memories where Grisha reveals that each of the nine titans have a special ability that's unique only to them. The Attack Titan's special ability allows its user to see memories from the future. So, Eren might have felt some connection to this place because of how he would influence Grisha to kill the royal family in this very location. Though, even if that's not the case, Eren admitting the caverns feel familiar foreshadows how he would influence Grisha's darkest act here.
Historia's Outburst About Titans Wiping Out Humanity
Season 3 of Attack on Titan was vital in establishing Historia -- both as an individual and her role in the story -- as she went from the shy and insecure Christa Lenz to finding her strength as the heir to the throne. She also plays a key part in setting Eren's plan into motion. It starts in Episode 7, "Wish," when she boldly declares, "Exterminate the titans? Who the hell wants to do that bullshit? I'm starting to hate humanity! Let 'em get wiped out by titans!" While she later admits this to be an overreaction and doesn't intentionally influence Eren, her words do foreshadow his genocide plan.
Another crucial event occurs later in Season 3 during an award ceremony, in which Eren and other medal recipients must kiss Historia's hand. It's been known that the Founding Titan's powers can only be utilized in junction with someone of royal blood and by making physical contact with Historia. From here, there is a noticeable change in Eren's character as he becomes the person fans know best in Season 4. But it isn't until "Memories of the Future" that it's revealed Eren had seen the future. When he kisses Historia's hand, he learns of what's to come -- and how to transcend time with his titan powers.
"Will We Finally... Be Free?"
At the end of Season 3, the Survey Corps are able to venture far past the walls of Paradis Island where they can finally set their sights on the ocean for the first time. However, this tender moment turns bittersweet far too soon. While everyone else is enthralled by this new wonder, Eren is cold and sorrowful, his mind seemingly someplace else as he points out to sea and says, "On the other side of the sea are enemies. Every part of this is exactly how I saw them in my dad's memories. If we kill all our enemies... over there... will we finally... be free?"
Turns out, Eren wasn't asking a hypothetical question. Rather, this scene reveals his true plan word for word: to eradicate everyone outside the walls to set the people of Paradis free. But he is visibly shaken, sounding both broken and desperate. Attack on Titan fans now know this is because he is riddled with a burden far too heavy for one person to carry, conflicted of the choices laid out in front of him. One can argue that he is grappling with his future actions and all the horrors that he will one day bring into fruition, as he questions whether genocide will truly bring them the freedom they desire.
