Perhaps Small World Riverworld is an artificial environment where all humans (and pre-humans) are reconstructed. The game probably explores interactions of individuals from many different cultures and time periods. Its underlying theme is quasi-religious: who did this? Why? How? The motivations of alien intelligences operating under ultra-ethical motives are explored.
Or perhaps Riverworld is just a fictional planet from a sci-fi book series... Hmmm.. Maybe it is based on the book?
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