One of the neat things about Uniracers is that you can rename any of the racers to pretty much anything you want to.
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But occasionally you'll put in a perfectly fine name only to have it rejected as being 'not cool enough'
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Through some testing, I was able to determine that the game uses a rudimentary check for... we'll call them 'off-color' words, and if it finds them anywhere in the name you've typed in, either for the individual unis or for teams, then it gets rejected.
I can't provide a list of all the words it rejects, though. You're on your own for that.