Nov 30, 2017 - Manga Shingeki No Kyojin Chapter 50' title='Manga Shingeki No Kyojin Chapter 50' />This Boy Can Fight Aliens. Taishou Chicchai san.
Season 2 literally ends right after the conversation between Commander Erwin, Levi, Hange, and Pixis, where they start to formulate a theory (unproven at that point) about the true nature of regular titans. The squad leaders have Connie report what they suspect about his village and family and then review what they know in light of the new information. Hange presents her theory and Levi remarks that he's been killing human beings for much of his life.
After Pixis and Hange leave, Levi is shocked that Erwin seems pleased at the new information. Erwin explains that it's because they are one step closer to the truth.
Levi wonders if the truth is worth it, considering their losses. Erwin declares that one day they will knock that wall hiding the truth down. That conversation takes place in chapter 51 (volume 13) of the manga.