Prequel: Demon To The Past?

It's a prequel novel to: Demon To The Future

It's a story about Zhou Su whom has died and transmigrated to another world as a wild beast. But at the same time he has also gotten a system to make him the strongest cultivator in the universe. With the help of the system he got his way thru many hurdles and joined a sect.

He the Peerless Immortal Swordsman the head disciple of the righteous sect defeated many demons and demonic cultivators and became famous in the world.