Gray P Switch

Gray P Switches (or Gray P-Switches) are objects in Super Mario World and its reissue. They appear identical to normal Switch Blocks except that they are gray with pink rims as opposed to blue with orange rims. When pressed, they turn some types of enemies into Gray Coins.

As revealed by hacking, Gray P Switches also possess the ability to transform Munchers into ordinary coins for the duration of their effect, similar to regular Switch Blocks in Super Mario Bros. 3. However, as Gray P Switches never appear in the same levels as Munchers in Super Mario World, this functionality cannot be seen in-game.

Gray P Switches are also unused in Super Mario Advance 4: Super Mario Bros. 3, where they would act as they originally did.

Trivia

 * In Super Mario Bros. 3 for the NES, Switch Blocks appear in a gray palette in the fortress levels, predating the Gray P Switches.