What happen before the Devil King of the Sixth Heaven create Samsara? What i want to ask is what is the life before the Devil King of the Sixth Heaven create Samsara (know as wheel-of-life,cycle-of-birth) and law of causation
This is an understandable confusion of 2 mythical concepts:

[Samsara] is the wheel of rebirth, divided into 6 realms:


Niraya (hell)
Preta (hungry ghosts)
Tiryak (animals )
Manushya (humans)
Asura (demi-gods)
Devas (deities)


The Six Heavens of the World of Desire are 6 places between earth and the Brahma heaven:


Chatur-maharaja-kayika (Heaven of the 4 heavenly kings)
Trayatrimsha (Heaven of the Thirty-three Gods)
Yama Heaven
Tushita (Heaven of Contentment)
Nirmanarati (Heaven of Enjoying the Conjured)
Paranirmita-vasha-vartin (Heaven of Freely Enjoying Things Conjured by Others)


The “Heaven of the Devil King” (Māra  in Sanskrit) resides in Paranirmita-vasha-vartin. Māra enjoys making free use of the desires of others to manipulate and control others according to their own will. The founder of the Nichiren lineage wrote:


  This world is the province of the Devil of the Sixth Heaven.  All of
  its people have been his karmic associates since time without
  beginning


Since manipulating someone's desire will have karmic consequences, this can be associated with Samsara, but the Devil King did not create Samsara, nor is it recorded who is assumed to have created the Six Heavens.