In the Super Mario Bros: The Lost Levels mode in Super Mario All-Stars, if Luigi stands on the left side of the first pair of seesaw platforms in Level 1-3 until the platforms break off, an invisible platform will appear on the right side. This does not happen with other similar platforms. (Footage recorded by me from a SNES emulator.)
Have you played the real Super Mario bros 2 (a.k.a. Lost Levels)? What's your take on this challenging and underappreciated Mario game?