The rebellion of Abū Yazīd (d. 947), leader of a Khārijite movement in Ifrīqiya, represented one of the most serious crises faced by the early Fatimid caliphate. During the uprising of the 940s, the Fatimid rule, still in its formative phase, was nearly overthrown by forces that conquered large portions of the territory and threatened the capital al-Mahdiyya. In Ismāʿīlī historiography, however, this political and military crisis was framed through an explicitly apocalyptic vocabulary. In the account of Idrīs ʿImād al-Dīn's ʿUyūn al-akhbār, Abū Yazīd is repeatedly described as the Dajjāl, the eschatological deceiver known from Islamic apocalyptic traditions whose appearance precedes the final triumph of the divinely guided leader. This paper argues that the portrayal of Abū Yazīd as the Dajjāl must be understood within the broader eschatological framework through which the early Fatimid regime articulated its legitimacy. The first Fatimid ruler had assumed the title al-Mahdī, while his successor ruled as al-Qāʾim, both titles deeply embedded in Islamic messianic and apocalyptic traditions. Within this symbolic horizon, identifying the dynasty's most dangerous adversary with the apocalyptic enemy allowed the Fatimid imam-caliph to frame the rebellion as part of a cosmic struggle between truth and deception. The paper further suggests that such apocalyptic enemy imagery was particularly mobilized during moments of acute political crisis and gradually receded as Fatimid rule consolidated.