Traveling Back and Forth to Different Worlds

Rebirth + time travel + system + urban immortality + fantasy of immortality + apocalypse + ancient times + cool writing (Brothers, this is a bad book. I don't want everyone to see this bad book. Please change it to another one. Sorry!) Chen Fan was reborn and returned to the past because of saving people. He unintentionally bound the system and traveled through various worlds with the system unlocked. Chen Fan traveled through the world of immortality, the world of doomsday, and the ancient Yan Dynasty, and became stronger step by step in the process of collecting soul fragments. The world of cultivating immortals: taking a mortal body and becoming a god... Doomsday world: Temporarily sealing one's own cultivation. He is obviously a strong man who can destroy a world, but he has to stay by the protagonist's side. Not only that, the countdown to doomsday is so bad that the protagonist's supplies are emptied in advance. Yan Chao's seal cultivation, with systematic modern knowledge, saved the people of the world from fire and water. Funny, sad, counterattack...