Game "mechanics" aren't copyrightable. https://www.gamasutra.com/view/news/273935/Texas_court_affirms_game_mechanics_not_protected_under_copyright_law.php https

Game "mechanics" aren't copyrightable. https://www.gamasutra.com/view/news/273935/Texas_court_affirms_game_mechanics_not_protected_under_copyright_law.php https://www.gamasutra.com/view/news/273935/Texas_court_affir...