Showcased here is an unpainted Mantis first shot. Mantis is cast in nonproduction colors lending it vast eye appeal. First shots, sometimes referred to as test shots, are used to test the steel molds prior to mass production. The color of the injection molded plastic was irrelevant since the figure served only test purposes. Typically non-production color first shots are more desireable to collectors. Although it is not apparent from the photos, this first shot is completely non-sonic welded allowing the figure to be taken apart. Not only do the limbs detach from the torso, but both the torso and thighs seperate into two halves since they are not sonic welded like a production figure.
Above is a comparison with the fully painted production figure. I think the visual differences between the two are strikingly obvious. Prototype collectors often attempt to acquire a series for a particular figure showing as many different production phases as possible. These series often begin to take shape by sheer luck. From there it becomes possible to dilligently search out complimentary pieces. It also exposes one to the plethora of work involved in bringing a toy from initial design to toy store shelves.
Collectors may also want to check out the other Mantis pre-production stages shown on the site: