I think it all depends on the location of both the game's origin and the originating copyright holders location... As to determining the laws of those locations regarding Parody of copyrighted material... It also may boil down to how the parody is handled... Is it truly a Parody, poking all sorts of fun and adding a lot of comedic value, or is it just a re-envisioned version, without all the stuff you typically find in a
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?
Plus, how willing is the copyright owner willing to make a fuss about it? Will the content offend the copyright owner enough to insight them into taking action? Will it effect partners of the copyright owner enough to get them to encourage the owner to take action? Is it a risky gamble you want to take? Would it be safer to get permission first?
You have to decide for yourself if the risk vs reward is something you're willing to gamble on...
Here are some thoughts/information I ran across for you to take a look at:
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Hope that helps...