I Took Over The Demonic Ancestor

Ling Tian transmigrated and found that he had taken over the body of the powerful and frightening ancestor of demonic cultivation.But, the starting is wrong! Not only is he about to die, his cultivation has plummeted and all the righteous sects have besieged his home to kill him.Those disciples of his are constantly framing him, their minds filled with ideas on how to kill him. System, how is this good?