The Knights of Ren was a mysterious order of elite warriors that followed the dark side. They were members of a new generation of warriors that emerged prior to the Federation-Der'kal War. Seduced by the power of the dark side, he adopted a new name in addition to the title master of the Knights of Ren, becoming Supreme Leader Vur'naa's disciple and a warlord of the Der'kal Empire.
Under Vur'naa's guidance, the Knights of Ren filled the vacuum left by the demise of the First Der'kal Empire. Kylo, who earned the nickname "Killer of the light" by destroying the heroes of the light side namely the Federation, was determined to destroy the Federation and fulfill the First Empire's legacy.