Shuubi no Kyojin, known in Japanese as 終尾の巨人, is the Founding Titan in its ultimate, transformed state from Attack on Titan (Shingeki no Kyojin). It is not a normal human character but a colossal Titan form tied to Eren Yeager near the series’ end. As a central force in the final conflict, it serves as the embodiment of the Rumbling and the story’s climactic threat, representing overwhelming destruction, the burden of power, and the consequences of Eren’s choices.