Train Doomsday Theory

Chen Yan woke up on a train heading towards the end. He lost all his memory and could not pass the train's identity verification, but he carried a return ticket that had never been sold by the train. The train will stop at civilizations that are about to be destroyed or have already been destroyed. The energy-depleted mining planet converts human value into jobs and output; the machines and artificial humans that inherit human heritage are convinced that the other is a fake; in a distant world, love is clearly marked with a price, and any relationship can be manufactured and replaced... At each stop, passengers must complete the task within the specified time and return before the train starts again. Those who fail to board the train will remain at the end of the world with that civilization. Other passengers are here to survive. Chen Yan doesn't even know what he is. He just wanted to figure out why the return ticket belonged to him and where the "go home" on the key pointed. But this train will only keep moving forward. And every stop it stops is the end of a civilization.