ImamSadiq (as) said: Imam Mahdi (as) will do the same act that the Holy Prophet (pbuh) done. As the holy Prophet (pbuh) that destroyed the act of Jaheliyyah (ignorance), the Imam will destroy current innovations (bid'ah) and then rejuvenates Islam.
4 Shias believe that all of the above must be infallible. On the basis of what this writer says, "Allah (SwT) did not bring about what was incumbent on Him. That is, after the passing away of Imam Hasan Askari (a.s.) He did not appoint Imam Mahdi (a.s.) immediately. Rather He has postponed the Imamate of Mahdi (a.s.) for the Last Age!!"TwelverShia Muslims believe that Imam Mahdi _ may Allah hasten his advent_ is the Twelfth Imam, who was born in 869 and was hidden by God at the age of five (874). He is still alive but has been in occultation, "awaiting the time that God has decreed for his return". Even Imam al-Mahdi does not know he is Imam al-Mahdi.
Themeaning of Shia: "Shia" means a group of followers, members of a group, as per Holy Quran, Surah Maryam verse 69: ثُمَّ لَنَنْزِعَنَّ مِنْ كُلِّ شِيْعَۃٍ اَيُّہُمْ اَشَدُّ عَلَي الرَّحْمٰنِ عِتِيًّا۶۹ۚ Then from every group We shall draw whichever of them was more defiant to the All-beneficent.Salam Imam Mahdi (may Allah hasten his reappearance), was born on 15th of shaban in the city of samera and he is now alive. he sees us, know us, in this time of occultation, even if people can see him, mostly they can't know him. in his occultation, people benefit from him like there benefit of sun behind cloud.
Ofcourse they wont succeed in corrupting twelver shia islam by saying that they don't believe in Imam Mahdi (ajj) . You can compare that to the laanatee sufis who founded the batiniyyat , then notice how these peoples claimed they follow AhlulBayt (pbuh) while they used the wala'i slogans to deviate peoples .
Below the aspects of this belief are declared: Who is the Savior according to Shia beliefs? Shias believe that the Savior (Mahdi (PBUH)) is the ninth descent of Imam Hussain (PBUH), the third Imam of Shias. Imam Hussain (PBUH) is the son of Imam Ali (PBUH) and Lady Fatimah (PBUH) the Prophet Muhammad's (PBUH&HP) daughter.TheBattle of Karbala ( Arabic: مَعْرَكَة كَرْبَلَاء) was fought on 10 October 680 (10 Muharram in the year 61 AH of the Islamic calendar) between the army of the second Umayyad caliph Yazid I ( r. 680-683) and a small army led by Husayn ibn Ali, the grandson of the Islamic prophet Muhammad, at Karbala, Sawad (modern-day rbOif4.