sentences:  The last revolt by a Nizari claimant was by al-Husayn's son Muhammad in 1162, but he was lured with false promises and executed by the vizier Tala'i ibn Ruzzik.There are indications that another of Nizar's sons, named Muhammad, had left for Yemen.None of these sons had been designated as successor by Nizar, however, so they lacked the legitimacy to become imam after him.