Best Answer
From the comment section you can see this:
"Free spirit" is the name of the "Rebel Unit" ending in the basic version of the game (click the "Original 48h version" under the game window).
I got the "Rebel Unit" ending for not interfering with any of the humans. but based on the text you might be able to get it as long as you don't free them all.
I got the Free Spirit from playing the original:
Pictures about "Free Spirit Ending on Chipset-0"
Lake Achievement - Free Spirit (100G), leave in the RV ending
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