Ball 'n' Chain is a type of spike ball in the Mario series first appearing in New Super Mario Bros. Wii as one of Bowser's traps that he set up in many castles and fortresses. To avoid it, they must stand away from it or stand on the brick in the center and the spike ball part of it won't touch them. Strangely, when Mario or Luigi use their Spin Jump attack, they will bounce off the spiky ball part instead of being attacked. In the New Super Mario Bros. games, they appear in World 7-Castle and Wendy's Castle with the same effect.