Immortality Debt

[No system + fantasy + no heroine] Long Feiyu came to this world because of a long-planned frame-up. His Dantian was destroyed, his cultivation was completely lost, and his consciousness was limited. But there is no end to the road, and one series of adventures led him to embark on the path of body refining, demon transformation, and technological immortality. He has been accumulating strength just to take revenge...