This is the best I can come up with, it works, kinda. And I know the syntax is wrong.

Thanks in avance

#showtooltip Fan of Knives
/targetenemy [noharm]
/startattack
/castsequence reset=target Fan of Knives, Fan of Knives, Fan of Knives. Fan of Knives, Fan of Knives, Crimson Tempest