You are conflating copyright and patents. Copyright is protection for the expression of an idea, like the art design. This is a patent issue, which is a protection of how something works.
If somehow I patent a vague mechanic like "a method of selecting weapons with the directions of an analogue stick or mouse, presented as an 8 direction on screen circle." Then I could sue Red Dead Redemption and Batman Arkham, despite there being no copyright infringement with whatever game I made with that feature.