Attack on Titan season 3 episode 13 The Town Where Everything Began
The Survey Corps treks through the forest under the darkness of a new moon, planning to retake the Shiganshina District in order to reach Eren's basement. On the way, they see a sleeping titan but manage to pass by without waking it up. The group arrives at the seemingly empty Shiganshina District and Eren easily blocks the hole in the outer wall with his titan hardening ability. Before Eren plugs the hole in the inner wall, Armin discovers a recently abandoned campsite and is given command to search for enemies planning an ambush. Armin assigns members of the Survey Corps to search for cavities within the walls and before long, Reiner bursts from a disguised hole in the wall and transforms into the Armored Titan. Suddenly, the Corps find themselves surrounded by Titans and the Beast Titan seals the inner entrance with a thrown boulder, trapping the horses within Shiganshina and preventing the Corps from using them to escape.