Al-Muttaqī was deposed on 20 Muharram 333 AH. Another report puts the event in Ṣafar. Tuzun granted him no respite; scarcely a year had passed before Tuzun himself was gone.
Al-Muttaqī died in prison, long after he had been blinded, in Shaʿbān 357 AH. He left but one son, Abū Manṣūr Muḥammad.

60 – al-Mustakfī bi-llāh ʿAbd Allah ibn al-Muktafī ibn al-Muʿtaḍid*
The caliph al-Mustakfī bi-llāh, Abū al-Qāsim ʿAbd Allah ibn al-Muktafī ʿAlī ibn al-Muʿtaḍid al-ʿAbbāsī, was short of stature, handsome, well-proportioned, fair-skinned with a rosy tinge, and lightly bearded at the sideburns. His mother was an umm walad concubine.
He received the oath of allegiance the very day al-Muttaqī was deposed, being forty-one years old at the time. Tuzun conducted the ceremony.
Soon thereafter Aḥmad ibn Būyah advanced, seizing Ahwāz, Basra, and Wāsiṭ. The Baghdad army, together with Tuzun, marched out to confront him, and the fighting between them lasted for months. Tuzun was repeatedly routed and plagued by epileptic fits, while Aḥmad, hard-pressed by famine and want, withdrew to Ahwāz. Tuzun cut the bridge behind him and returned to Baghdad, preoccupied with his own condition. (1)
Abū al-Faraj al-Samarri was made vizier, but Tuzun dismissed him after forty days and fined him 300,000 dinars.