Attack On Titan's final season reached its first pivotal turning point with the latest episode, "Declaration of War". (Spoilers Follow) Eren Jaeger finally revealed himself, having cornered his old foe Reiner Braun in a basement where the two "catch up" with one another. It's a terrifying conversation for poor Reiner, who knows with all certainty that Eren has arrived to exact some kind of terrible payback against Marley, for all the death and suffering Reiner's titan's team caused by tearing down the walls. And he's not wrong about that. However, before Eren unleashes pure carnage against Marley's leaders, Attack On Titan fans get the emotional punch of this dark callback to season 2:
Attack On Titan's early seasons revolved around the mystery of the special Titans, who shattered the walls of Paradis Island and unleashed the hell of the Titans upon the people living there. Season 2 deepened things with the reveal that the Armored, Female, and Colossal Titans were piloted by human operatives that had infiltrated the Survey Corps. That mystery ended in the heartbreak of Eren having to learn that his friends and mentors during training - Reiner and Bertolt - were actually the Armored and Colossal Titan.
As you can see below, the moment that Reiner (in a fit of PTSD mania) reveals he is the Armored Titan, was truly a heartbreaking one for Eren. The scene is given powerful reversal in this new moment between Eren and Reiner, in which Eren is finally given the chance to turn the tables and break Reiner's spirit, by annihilating the homeland Reiner fought so hard for. As the episode ends, Eren transforms into the Founding Titan and takes out the stage where Marley's leader Willy Tybur is holding a milestone event with the nation's leaders in attendance. It looks like Eren is about to shatter Marely's society the way that Reiner shattered Paradis Island's world. The long-awaited war is now officially on.
Attack on Titan fans are applauding the level of detail that Mappa has put into this pivotal moment between Eren and Reiner - right down to the light of Eren's epic transformation being reflected in Reiner's eyes. The Karma of what Reiner unleashed by taking on Marley's cause is finally coming back on him.