Opening (Episode)

"Hey, say something! Who's the enemy?!"

- Eren demands answers from Ymir

Opening (開口) is the 9th episode of the 2nd season and the 34th episode overall of the Attack on Titan anime, produced by Wit Studio and Production I.G.

Overview
While the Scouts advance towards the Forest of Giant Trees, Eren and Ymir attempt to get answers from Reiner and Bertholdt. While receiving few answers, they discover that Reiner's personality has split under the pressure from living for two different goals.

While Ymir wonders about the warriors' goal and the reason for the Beast Titan's presence, Eren expresses his rage towards the traitors. The true enemy of humanity remains a mystery to Eren, though the Scouts are closing in on the forest with the intent of saving him from his fate.

Summary
The Scout Regiment, Garrison Regiment, and Military Police Regiment set out from Wall Rose. Meanwhile, Hange attempts to search for a horse, determined to ride for Ragako to investigate the Titan found at Conny's house. Moblit, refusing to let Hange roam around while still heavily injured, agrees to ride for Ragako while she stays behind and recovers. At the head of the troops, Commander Erwin establishes a long-distance enemy scouting formation as they head for the Forest of Giant Trees.

Over in the forest, Reiner and Bertholdt see that Eren has finally woken up. Eren sees that he is missing both his arms, and Ymir shows him that she too is slowly recovering lost limbs. Reiner apologizes for Eren's dismemberment, saying that he was in a hurry to tear him out of his Titan form and did not take his arms into account. Eren attempts to transform again, but Ymir stops him, showing him that they are in no position to fight. Being in a Forest of Giant Trees, they are far from both Wall Rose and Wall Maria, and a significant number of Titans can be seen lurking around their position. Ymir then notes that Reiner and Bertholdt have the advantage of ODM gear, Reiner having stolen Eren's gear while he was unconscious.

Reiner informs the two that neither of them could transform into Titans in the first place while still recovering from their injuries. Eren, still outraged at the traitors, disregards the claim. Ymir takes their word for it and asks what Reiner and Bertholdt plan to do with them now that they have been captured. Reiner tells them that they will be taken to their hometown, but only after nightfall after they've recovered their strength and the Titans have become inactive. Ymir wonders why Reiner did not simply continue running for Wall Maria as the Armored Titan, but Reiner gives no definite answer.

Eren begins considering his options. He believes transforming into a Titan and escaping would not be difficult unless Reiner's claim that he is unable to transform is true. Additionally, a weaker transformed Titan could be caught and eaten by the Titans lurking below. Eren also considers that Reiner and Bertholdt will make their next move before nightfall itself, while he and Ymir are still recovering. Recalling the end of his battle with Reiner, Eren worries for the safety of the Scouts who might be searching for him. Ymir speaks with Reiner, recalling the Titans at Utgard who could move around at night and wondering if the Titans around them will also move at nighttime. Reiner guarantees that these Titans cannot move at night, claiming that Ymir should already be aware of this. This causes Eren to question what Ymir knows and where her allegiances lie. Recognizing his disadvantage, Eren decides to suppress his emotions and wait for further information.

Erwin's scouting formation comes across a Titan on the right wing, but he orders the troops to merge with the center and stick to their straight-forward route towards the forest. Hannes calls for Mikasa to slow her advance before she merges with the vanguard, which would throw off the formation. He understands her concern for Eren's safety and reminds her of their earlier conversation, assuring her that Eren will be fine on his own until they arrive to save him.

Back at the forest, Ymir becomes parched and asks for water, but Reiner says that they are unable to care for anyone's needs in their current situation. Reiner realizes that all of them have been working constantly since the previous day's morning when the Titans were first spotted, and he suggests that they should all receive promotions once the situation is over.

Ymir and Eren are confused, and Bertholdt begins to grow worried. When Ymir questions his strange behavior, Reiner thanks her for finding the cannon back at Utgard which saved him. He also recalls Christa treating his injuries afterwards, wondering if she has feelings for him.

Eren brings the moment to a halt, demanding answers for Reiner's sudden change of character. Seeing Bertholdt's concern, Ymir realizes that this is not a new occurrence. Bertholdt addresses Reiner, telling him that they are warriors and not soldiers. Reiner begins to panic, suddenly recalling a moment from the Struggle for Trost in which he restrained Marco Bodt, feeding him to a Titan. Bertholdt and Annie were also there, watching him die with tears in their eyes. As Marco was eaten alive, Reiner suddenly became unaware of the situation, wondering why Marco was being eaten. Reiner collapses with stress after remembering his true self, and Ymir realizes what he is doing. Overwhelmed by the stress of living a soldier's life for the humans of the Walls while also working as a warrior to destroy them eventually split Reiner's mind into two personas where the soldier does not recall the actions of the warrior. Ymir's analysis hits too close to home, and Reiner demands that she stop talking.

Eren speaks up, demanding to know what the two traitors were thinking three years ago when Eren told them how his mother died when they attacked Shiganshina. Bertholdt admits that he truly felt sorry for Eren when he learned of this. Eren, having lost all sympathy for the two, labels them as murderers of thousands of innocent lives and can no longer be considered human. Reiner breaks, telling Eren that they are aware of what they are and that reminding them of their sins will not accomplish anything. With nothing left to say, Eren assures them that he will eventually kill them in the most excruciating ways he can make possible. Ymir is tired of Eren's emotional outbursts and asks for him to stop.

Ymir changes the subject, asking Reiner and Bertholdt about the "monkey" that appeared at Utgard, whom they must know well considering their awestruck reactions to its appearance at the castle. Ymir believes that the monkey, the Beast Titan, was responsible for the recent Titan invasion, possibly as a means of testing humanity's strength. She also claims that if Reiner and Bertholdt are able to find the Beast Titan, they will be able to return home. Eren demands for Ymir to tell him everything she knows, but Ymir says that killing Reiner and Bertholdt will in no way solve the crisis brought against the Walls. Eren wonders who humanity's true enemy is, and Ymir considers an answer.

Reiner interrupts her, claiming that the world in the Walls has no future. Reiner says that given what she knows, it may be possible for her to join them given the fact that both her and the warriors share a concern for "Christa" for their own reasons. Reiner says that even though Ymir's own safety might not be guaranteed, Christa may have better chances of surviving future conflicts if she joins them rather than staying with Eren. Still confused over the turn the conversation has taken, Eren demands to know who their enemy is. Ymir is unsure.

Reiner and Bertholdt prepare to take Eren and Ymir and move out when suddenly a line of signal flares is spotted on the horizon, heralding the arrival of the Scout Regiment much sooner than expected. Eren is dissatisfied with the conversation, noting that only an hour remains until sunset.

Titan Regeneration
''Those with the power to become Titans possess an inherent ability to regenerate. Their limbs can be dismembered and their internal organs destroyed, but as long as they survive, their bodies will regenerate back to normal given sufficient time.''