Cultivation to Become a Demon Lord from Scratch

Because of a "strange dream", Xiao Lan accidentally traveled to a cave where demons were rampant. Then, he encountered a system disguised as a "devil". Under her deception, he embarked on a long and alternative path to becoming an immortal... The ferocious beasts that devoured the world in the Xuanqing Cave, the magic that rewritten cause and effect in the Xuanhuang Cave, and the artifacts that reversed life and death in the Lingbao Cave... These were supposed to be opportunities for him to become an immortal, but instead he became the most powerful demon in the world!