Heir ( Arabic:Wareth, وارث)
In some prayers and narratives from Imams, Imam Mahdi has been referred to as Heir. The Prophet say in Ghadyriyeh sermon: That Imam would be the Heir of all knowledge, all perfection, and all degrees of prophets, Imams and his honorable forefathers. In other words he would possess all that previous prophets and Imams had had.
Promised (Arabic: موعود)
The promised is one of the famous names of that Imam which almost all revealed religions use to refer to him. Imam Sajjad while interpreting the verse and what they have been promised ( Arabic: و ما توعدون) , talks about the reason for such naming: it means the uprising of the Qaem of Mohammad family PBUH. His Appearance has been promised to all prophets and previous nations. Hence in his Ziarah (Pilgrimage text) it is said: peace be upon that Mahdi who God promised to unite and integrate people by him.
The last of Gaurdians (Arabic:خاتم الاوصیاء)
One of the titles of Imam Mahdi (May Allah Hasten His Reappearance) is The Last of guardians; because he is the last guardian of The Prophet PBUH and the last innocent Imam that with his Appearance would establish the system of Islamic justice all over the world.
Servant of Imam Hasan Askari has narrated that once I was at Imam Mahdi’s service, he introduced himself to me: I am the last of the Guardians for the sake of whom God the Almighty removes hardships and disorders from my family and my followers.
Caller (Arabic: داعی)
In one ziarah he has been referred to as “caller towards Allah ”(Arabic: داعی الله): peace be upon you the caller towards Allah. It has been narrated about the reason for this naming that he has been assigned a mission by God to invite people to God. He would work on this path so that the divine faith is established all over the world and so that no school of thought except God’s religion claims governance and guidance.
There has been more than 300 titles mentioned for Imam Zaman, each of which focusing on one particular aspect of his characteristic traits, mental and moral qualities. For instance: Mahdi, Mansour, Qaem, Hojatollah, Saheb-al-Amr, Saleh Khalaf, Baqiyatallah, Montaqem, the promised, the last of Guardians, The Caller, Baset, Saer, Sahib-al-Zaman, Valiollah, Rahman Khalifa, Borhan, Sayyed, and Montazar.