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I read a lot of books in the 1980's and some I borrowed from friends. I would like to find this series if anyone can figure out what it was.
The story started out with a person or several persons escaping in a large ship from certain doom. They traveled across the galaxy searching for something that was spread out across 5 planets. They could transform their body mass to become any other being or creature as long as it had the same or less mass.
They were chased across the galaxy by robots called "Val's" or something like that. Eventually they found the last clue on Earth. It was a secret kept by native Indians or air base or something like that. Again my memory is fuzzy on the details.
If I recall this was either a 3 book series or 5 book series.