Conductaurs are people that have been merged with an engine , turning them into literal taurtrains ( they keep the legs though so no wheels ) this merge is permanent , but they're able to consume fuel and connect to Wagons*
Wagons or more commonly reffered Wagontaurs are people who have been merged with a wagon , they retain their legs but they're not able to pull other Wagons , as they're only able to connect to them but of they're connected to a Conductaur they lose all ability to move their legs as the conductaur esentially hijacks their nervous system ( they're still able to move their torsos but they're just enjoying the ride ) this "hijacking" allow the Conductaur to see through their eyes and feel through their body too !! ( This goes for the entire systaur to if someone is petting their body everyone can feel it ( when they try to sleep is common for everyone to pet themselves ))
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Strays are caused whenever a conductaur accidentally detaches a wagon when these are asleep , if you notice a wagon detach you should tell the most near wagon to notify the conductaur !! But ocasionally there are volunteers that want to remain as a wagontaur , these wagons have been issued a volunteer staff clothing ( depends on the local station ) if they're wearing it that means they're in service ! If they're not then they aren't !!