I was astonished a few years ago when the ex-president of Iran, Ahmedi Najad, threatened the world with an upcoming MAHDI at a full UN General Assembly!
I thought such superstitions only defame and make mockery of the glorious Deen-il-Islam.
Perhaps you know that even today, for a great majority of Shi'as, the best deed is to wait for "Imam" Mahdi.