Attack on Skytree

Overview

A special anime featuring a battle against the Colossal Titan screened at the Tokyo Skytree. In the short, the characters from Shingeki no Kyojin are part of the Sky Survey Corps, protecting the Wall Skytree, a section of the walled city that contains the Skytree. The Sky Survey Corps find that the Wall Skytree is under attack by an army of titans, including a giant 350 meter-class titan that has suddenly appeared next to the Skytree and remains motionless. (Source: Anime Now!)

Source: AniList