WARNING: The following article contains spoilers from the Attack on Titan manga which is crucial to the plot. Read ahead at your own discretion!
Chapters 120-121 play a crucial role in dissecting the roles of the Yeager brothers in reaching an “end” to the whole conflict in Attack on Titan. However, things turn out to be very different once they see their father’s memories. The prospect of Eren coercing his father into killing the Reiss family and triggering this whole concept changed Attack on Titan overnight.
While this will go down in history as one of the most interesting plot points introduced right at what seemed like a climax, it’s key to break down this event and address important issues.
Setting the stage for Eren’s memories
To run you up on the context, Grisha was to get the Founding Titan from the royal family. Subsequently, he reaches the cathedral where the family was praying and gets into an argument with Frieda Reiss, before transforming and killing her family before ultimately eating her. We know that Eren saw this side of the story when he kissed Historia’s hand initially. To know more about that, check this article out!
When the story progresses to this point, it becomes clear that Eren saw way more than what was initially shown. To put it simply, Eren saw the events of chapters 120-121 unfold four years before they were to happen. Eren, saw Grisha’s memories of this account. However, these memories of Grisha were ones that showed Eren and Zeke watching him. How could Grisha see them, you ask? It’s because the Attack Titan can see into the future.
Did Eren travel back in time with Zeke?
No, he didn’t. Eren and Zeke just managed to see their father’s memories by triggering the full powers of the Founding Titan. Think of it this way; Eren and Zeke did not physically go back in time. According to the Attack on Titan universe that is something impossible. They created a construct in which they were able to see everything, something like a 4D film.
However, when you take the abilities of the Attack Titan into account, the story gets more complex. What we see in the story has been seen by Grisha already.
Grisha, Eren, and everything in between
So, we now know that Zeke and Eren weren’t actually present when this happened. They were just watching a “film” of their father’s memories. So, why did Grisha hug Zeke, or look right where Eren is?
As mentioned before, the Attack Titan has the ability to look into the future. This means that Grisha saw Eren and Zeke viewing his memories in the future. By that logic, Grisha saw himself through Eren’s eyes. This means that when Grisha actually went to retake the Founding Titan, he already saw these certain scenes. This is why he knew where Eren was standing and where Zeke was standing while they were viewing these memories.
This means that Eren didn’t go back in time and “coerce” Grisha. Eren said these words while watching, knowing that this was something he has to do thanks to the memories he saw when he kissed Historia’s hand (he knew in the future he would talk to his dad, so when the time came he just did what he had to).
Consequently, Grisha did what was needed because he had seen into the future and knew that when he would hesitate, Eren would try to reason with him. Eren coercing him isn’t in real-time. Grisha can’t see Eren, but he could hear him and knows this happens because, you guessed it, he has seen this in a future memory before! Or he had a future memory right when he was there.
Memories are passed on via Paths. Meaning, they don’t happen in real time. Even if a memory viewed is like an hour long, the actual time that passed on in the real world would be negligible.
In this panel. Eren is seen thanking Zeke after he confronts him for manipulating Grisha. Here, Eren’s words serve as an explanation- Grisha wouldn’t have been able to hear Eren if it wasn’t for the two of them watching his memories. This also shows the extent to which Eren managed to influence Grisha by highlighting the possibility that Eren carefully picked out some memories to show his father.
Explaining the chapter 139 phenomena
Eren managing to manipulate memories of Armin had nothing to do with the Attack Titan. The ability of Eren to transcend the concept of time and trigger these memories after his death had to with the powers Ymir lent him. By the end of the story, Eren’s titan is the male counterpart to Ymir’s founding titan. It had the power of seeing the future, past and present which is why Eren could break the barrier of time.
Therefore, this case cannot act as a supporting argument that Eren time traveled ever before.
In conclusion, Eren did not time travel during the events of chapter 120-121. He was simply watching his father’s memories with Zeke; the same ones that Grisha had already seen before. This is why Grisha carefully chose his words and begged Zeke to stop Eren, knowing this was his one chance to pass on a message. When Grisha would have seen this memory during his time as the Attack Titan inheritor, he heard Eren’s voice. Therefore, when he actually went to carry out the plan, he knew that he would hesitate before he would hear his son.