The (C) is automatically assigned to you. You can add the (C) as a notification as to who the copyright as assigned to. The copyright will last with you your entire life, and then a further 50 years after your death to your next of kin.
If you wrote a game called "The Legend of Dark Basic", you could copyright the game, but you couldn't copyright the words. However, you could create a 'style' (for example the font, size, colours, etc), and claim this is a trade mark. However, other people could also 'rip' this from you and claim it to be there own (the words, not the game which is still copyrighted).
However, if you DID register your Trademark, you could then have the (R), which means nobody would legally be able to use those words, in your style anywhere unless they had your permission to do so.
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~ J ~