I have a very powerful role and I will be extremely useful to the town later on. You might be able to win without me but it will be much harder.
Your role isn't THAT powerful, you have a one time kill and can investigate when you like but you give up your immunity.
So I don't see how your role is so powerful we can't win without you.
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Individual roles are not always anti-town and sometimes they are vitally important.
Well they aren't Pro-town either, hence why they are individual .