Atabeg Ali al-Mustasib was an exiled ruler of Semphar who was forced to live in the small community of Iris Well Spring located to the east of Semphar. A jailer visited him yearly to deliver supplies and confirm that he remained in exile without fleeing.
Ali viewed the Tuigan horde under Yamun Khahan as a way to possibly retain control in Semphar. The Khahan's son, Hubadai, used information gathered from Ali to plan his invasion of Semphar. Ali was rewarded for this information with a spot on Hubadai's military council. Ali's daughter was also taken as a royal concubine to ensure his further cooperation.