Hajime Isayama's Attack on Titan has always been something of an emotional roller coaster - humans are at the brink of extinction because of the Titan presence and there are more than just Titans that pose a threat to their survival.
However, the past few chapters and up to the most recent one, Chapter 84, has put the cast, as well as the readers, in what has been one of the most emotionally engaging sequences to date.
At the helm is Levi Ackerman and he has quite the decision to make: save Erwin Smith, the commander of the Survey Corps, or save Armin Arlert, childhood friend of main protagonists Eren Yeager and Mikasa Ackerman. Both are in the brink of death and Levi has Titan serum, but he can only choose one.
Now, with Chapter 84 published and recently translated, fans finally know who Levi chooses: Armin. Of course, considering the nature of the Attack on Titan series, his decision wasn't one that was made easily.
Both characters have been particularly important to the plot up to this point, so in theory there are merits to saving both of them. For Commander Erwin, he is the leader of the Survey Corps and has been behind the vast majority of the action that has happened up to this point. You don't necessarily see him much, with most readers associating the group with Levi, but he is the one who typically comes up with the plans that they carry out. For example, it was his plan to use a bunch of recruits as decoys so that Levi could attack the Beast Titan from behind to kill it. The plan was successful for the most part, though it was during this operation that Erwin wound up in his present situation.
Meanwhile, Armin has been with Eren and Mikasa since the start of the series and is seen quite often. He isn't much of a fighter (at least compared to the likes of some of his peers), but he more than makes up for that with his bravery and intelligence. Armin has been responsible for the plans behind a variety of battles that marked critical turning points in the story. For instance, it was he who realized that Annie Leonhart was a Titan Shifter and subsequently formulated a strategy to capture her. Most recently, he came up with the plan to finally subdue Bertolt Hoover, aka the Colossal Titan. The plan was successful, but it was also during the plan's execution that Armin found himself at death's door.
Everyone on the scene presented good arguments for why one or the other should be given a second chance at life: for Erwin, it was his status as a symbol of hope, while for Armin, it was the various plans that he came up with throughout the series.
However, when it was finally time for Levi to make his decision, it wasn't any of those previous arguments that swayed him: it was his feelings toward Erwin and the dreams he was forced to give up as commander of the Survey Corps. It was also Armin's continued dream to the see the ocean despite the grim situation humanity is in.
"[Erwin] had no choice but to become a demon, and we were the ones that wished that upon him ..." Levi said when questioned. "And just when he was finally freed from this hell of a world, we tried to drag him right back into it."
Prior to that declaration we get to see two things unfold: first off, Armin reviving, much to the shock of everyone nearby. Second, Bertolt dies.
Just when everyone resigned themselves to losing their friend, a Titanized form of Armin bursts out of nowhere and devours Bertolt, seemingly acquiring his powers as a Colossal Titan in the process. In his final words, Bertolt begs his "former" friends from the academy to save him, before realizing that they wouldn't help, opting to call out for Annie and Reiner instead.
The final scene shows the revived Armin unconscious as Erin, Mikasa, Connie and Jean tearfully surround him.
Of course, with a rare happy ending like that, who knows what hell awaits the cast in the upcoming chapters?
