[@Revans Exile]
There are stories among the soldiers of the higher ups who can vanish from the air only to reappear to deal the death blow. However for the lowly recruits it's just a dream. As for space craft, such schematics have been found in the ruins, but those eggheads in research and development haven't found a convenient way to power it for more than a few minutes, and even then sensors can still trace the ship.