Well there isn't that much need for canon
There are races that somehow ended up in space, they mostly developed independant of eachother so there are no attachments
I'll just try to help balancing them against eachother, whatever you do with your nation is really up to you
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Want a blend of
fantasy and
sci-fi? Try the total conversion
Dominions 3000 mod with a new and fully modded solar system map.
Dragons wanted? Try the
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New and different undead nation? Try
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In for a whole new sort of game? Then try my scenario map
Gang Wars.