There was an old theory that somewhere on Mudos there was a ground base Vykkers Labs. This suggest that maybe the feeco trains travel to this ground base which would so happen to be the main Vykker's facility.
I can definitly see a scene in which there is this vast labortory with Vykkers ships docking and redocking with it. Almost like a huge hub or Blimp Hanger Oddworld style.
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