Often the fact of copyright ownership and its protection by law is not enough. For example, a modification of the source code of a game automatically turns it into a new unique object that is not subject to copyright protection for the existing code. The creator of the modified code gets the opportunity to legally use his work, possibly completely repeating the existing game.
In case of illegal use of copyright objects, the dispute is most often resolved in court. To protect your interests, you will need to provide proof of copyright to the object. During the trial, it’s quite difficult to determine when the work was created and provide sufficient evidence of copyright.
In addition, the lack of the necessary level of protection for the game content provokes dishonest competitors, inattentive users, and dishonest employees to illegal use of your copyright.