Lacking a conventional army, in order to survive, they started using unconventional tactics such as assassination of prominent enemy figures and psychological warfare.
[1][2] Most of the assassinations by the Nizaris took place during the first decades of their struggle, which helped them to create a local political power.
[3][2] [The assassination of Nizam al-Mulk] was the first of a long series of such attacks which, in a calculated war of terror, brought sudden death to sovereigns, princes, generals, governors, and even divines who had condemned Ismaili doctrines and authorized the suppression of those who professed them.Those assassinated were usually the enemies of the Nizari Ismaili sect, but also sometimes people of political importance who were killed in exchange for money paid by some local ruler.
[3][2] It should be taken into account that medieval Arabic sources generally tend to attribute most of the assassinations of this period to the Ismailis.
[7] The names of the assassin and their victims were written in a roll of honor kept in Alamut Castle, recorded by later Muslim authors.