Railway Survival: 100 Times the Difficulty and 1000 Times the Reward

(Infinite flow + railway survival + fourth dimension + big universe era) Infinitely upgradeable trains, infinitely extending railway tracks, constantly passing through high mountains, endless deserts, vast ice fields... Rules of survival: 1. Must reach the designated station within the specified time, failure will be eliminated. 2. Be careful when going to the toilet in the wild. There might be a pack of wolves behind you at some point. 3. Only by upgrading trains as soon as possible can you get more benefits in large and small stations.