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Mystery Package - Lock Box
This package has a thin veneer that conceals the box within. It is some kind of lock box, but it could be a normal one. The box itself is protected from scanning with a small neutrino generator.
Mystery Package - Lock Box is a lock box that has a chance to open and reveal either a a regular Cardassian Lock Box or Ferengi Lock Box, or the much rarer Cardassian Lock Box - Gold or Ferengi Lock Box - Gold (chance tested with 100 Mystery Packages - 1:100).