ON/OFF Switch

An ON/OFF switch, also known as ON Blocks , Switches or ON/OFF Blocks , is a stationary object found in Super Mario World, its remakes, and Super Mario Maker 2.

Super Mario World / Super Mario World: Super Mario Advance 2
In Super Mario World, it can be used by Mario or Luigi either to change the path that a line-guided platform is traveling on or, in #4 Ludwig's Castle, to toggle the direction in which the falling ceiling is moving. The switches can be turned on or off either by jumping against them from below, whirling Cape Mario's cape next to them or throwing an object, like a Koopa Shell, at them. Since using the cape to activate a block can hit it multiple times in succession, toggling an ON/OFF Switch that way does not guarantee that it will end up in the state intended by the player.

Apart from #4 Ludwig's Castle, they are mostly found in the levels Donut Plains 3 and Way Cool, where the switches are abundant. They are sometimes guarded by a Fuzzy.

Super Mario Maker 2
In Super Mario Maker 2, they appear as a placeable course element. When hit by Mario, they can transform red/blue blocks into outlines or vice versa. In this game, they have more saturated red and blue palettes rather than having magenta and slate palettes. They can also transform other objects such as tracks, Conveyor Belts and Spike Blocks.