So there’s a difference between music copyright and an idea for a game…you cannot copyright an idea in your head - it is not a product…music is a finished product…when you create a piece of art - it is held under something called common law trademark - if you made the art then you own the trademark.
But that’s like saying…I have an idea for a song - without actually having written anything - you want to just copyright a chord progression…which you cannot…
just like how you cannot copyright game mechanics - hence the reason why there are so many clones of games.