Why Grisha Yeager and Frieda Reiss is an integral part of Eren and Zeke's journey in Attack on Titan Final season part 2

According to the preview shown at the end of Episode 3, the next episode of Attack on Titan Final season Part 2 is set to feature a revelation to the Yeager brothers, Zeke and Eren.

What did eren show grisha to convince him to give eren his titan? (Before the retcon) : r/titanfolk

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Attack On Titan: How Important Was Grisha To Eren's Plan?

Borderline, Attack on Titan Wiki

Why did Grisha tell Zeke to stop Eren here? This is when manga was in kino phases, everyone loved it, and nobody questioned it then. Any opinions? : r/titanfolk

Hiroshi Tsuchida – THE REVIEW MONSTER

An Unknown Attack Titan Ability Revealed! AoT, Season 4 Part 2, Episode 20 “Memories of the Future” Review [Top 5] – OTAKU SINH

Eren Manipulates Grisha to Survive – Attack on Titan S4 Ep 20 Review – In Asian Spaces

Shingeki no Kyojin – THE REVIEW MONSTER

How did Grisha see Zeke in episode 79 of Attack on Titan? - Quora