This study highlights a hitherto neglected trope of Muslim apocalyptic literature—namely, that in a region known as al-Talaqan there awaits the future Mahdi a great treasure that will gain him a mighty army to successfully fight the final battle against evil. Tracing the trope’s origin in Zoroastrian apoclaypticism and its subsequent dissemination in a wide array of Muslim apocalyptic traditions, this paper argues that this apocalyptic trope ultimately entered into Muslim apocalypticism, in particular Shi‘i apocalypticism, during the Zaydi revolt against the ‘Abbasids led by the Hasanid Yahya b. ‘Abdallah in the year 176/792. The paper then explores how the revolt of Yahya b. ‘Abdallah shaped how the ‘treasures of al-Talaqan’ functioned in Muslim apocalypticism and how Yahya’s personality and the revolt he inspired continued to leave an indelible imprint on Imami apocalypticism thereafter.