Bystander

Two months after Historia's coronation, the military has purged the old puppet regime. Eren perfects his Titan hardening ability; with it, Hange develops a new guillotine weapon that allows them to easily kill Titans without fighting or risking human life. At Jean's prompting, Eren tries to remember the Scout who appeared in his father's memories from when Historia touched him. He realizes it was Training Corps Commander Keith Shadis, and the Scouts visit him. Keith explains that he met Grisha, who claimed to have amnesia, twenty years ago outside Wall Maria. Grisha worked as a doctor, married Carla, and had Eren. After the Fall of Wall Maria in Shiganshina, he took Eren into the woods, telling him to avenge his mother. Keith later found Eren unconscious and alone, with the key around his neck. Keith resigned as Commander, installing Erwin as the new one. Keith had hoped Eren would avoid becoming like Grisha but Eren says he is merely the son of a special man.