Spinner

A Ball 'n' Chain is, quite simply, a rotating ball on a chain swinging on a pivot. Bowser uses these as cautionary weapons against invaders, but intruders in the Castles can hop into the brick in the center, giving them a safe haven. They were found in a lot of the Castles and Fortresses in Super Mario World, as well as a reappearence in New Super Mario Bros.. It is unknown if they will appear again.