Ikoral was Vindican's master and one of the most respected sith of his time to the point that even the Emperor took interest in him. After seeing the decadence and corruption within the empire he decided to turn against both Republic and the Empire and start his own war alongside thousands of loyal pureblood Sith. He was confronted and defeated by a strike team led by the protagonist. You need to be at least at level 45 to defeat him. I suggest you watching battle on the red reaper in youtube