An item found in EarthBound which deals damage to mechanical enemies. Though despite them being at least partially mechanical in nature, they do not work on Starmen or any variation of Starmen. Rust Promoters can be purchased at Burglin Park in Twoson from a junk salesman and in Threed behind the pizza shop. Rust Promoters can also be purchased from the salesman behind the Drugstore in Dusty Dunes Desert.