While Marley plans to invade Paradis to strengthen their weakening military and retrieve the Founding Titan, the Survey Corps lay an attack in their homeland.
In the second part of the season, aware of the global anti-Eldian sentiment resulting from Marleyan propaganda, Eren Jaeger preemptively targets the world outside of Paradis with the Rumbling, unleashing millions of Colossal-like Wall Titans in a widespread effort to kill all life beyond the island.
In the third and fourth parts of the season, the Alliance led by members of the Survey Corps and Warrior Unit head to Marley in order to stop Eren's Founding Titan and end the Rumbling.
[2] In the United States, Adult Swim's Toonami programming block began airing then-Funimation's English dub on January 10, 2021, at 12:30 a.m.
[12] For the second half of The Final Chapters, the ending theme is "To You 2,000... or... 20,000 Years From Now..." (二千年... 若しくは... 二万年後の君へ・・・, Ni-sen Nen... Moshiku wa... Ni-man Nen-go no Kimi e...) performed by Linked Horizon.
Lady Azumabito arrives with a Hizuru delegation and an aircraft powered by Iceburst Stone, which she describes as the "world's first flying boat".
For leaking information about Eren's imprisonment to the press, Hange incarcerates four Survey Corps members including Floch and Louise.
As the Wall Titans walk off into the sunset, the people in Trost District argue about the cost in lives and devastation of Eren's strategy caused by the Rumbling.
Backed by the Jaegerists, he confronts the Volunteers with the reality that their only choice is to accept submission to the New Eldian Empire or death, the latter quickly demonstrated by shooting one of them dead.
Floch then tries to convince Mikasa and a shaken Jean to give up fighting and retire as heroes of Paradis, mentioning Hange and Levi's deaths.
Managing to barrel through the fight, Floch attempts to destroy the ship's hull with a Thunder Spear but is shot down by Gabi and falls into the sea.
Noticing a captured Marleyan cruiser at the shore, Magath decides to remain behind to destroy it and runs into Shadis, who had followed them to the port and taken out the train.
The two men exchange words of mutual respect then destroy the cruiser at the cost of their own lives to save the world while the others sail off to Odiha.
Thinking her father is already dead, Annie decides to stay behind on the ship with Gabi, Falco, Yelena, and the Azumabito, while the remaining warriors, scouts, and Onyankopon take the flying boat to stop Eren.
Chapter 3 – The Battle of Heaven and Earth: The Scouts and Warriors lands on Eren's rib cage, and incapacitate the Beast Titan realizing that it is just a shell with Zeke nowhere to be found.
Falco flies down to the Liberio refugees, but the reunion between the Warriors and their families is cut short when the source turns the nearby Eldians, including Jean, Connie, and Gabi, into Titans to help defend it.
Ymir is thus freed from the Paths allowing her to pass on, and the Titan powers, along with the source, disappear from the world, turning all the Eldians permanently back into humans.
After Eren's death, a conversation between Armin and Eren is shown where Eren talks about why he treated Armin and Mikasa badly earlier, talks about the effect his possession of both the Founding and Attack titan had on his mind, and reveals that eighty percent of the world's population will be wiped out by the end of the Rumbling and that he realised it was impossible for him to avoid doing the Rumbling after repeatedly trying to find a way to avoid it, so he decided to go along with it to protect his friends and ensure their statuses would be elevated to the saviors of humanity in the rest of the world, alongside giving them the long, fulfilling lives he wanted them to have in a world free of Titans.