 The Super Mario Bros. 2 that North Americans know is not the same Super Mario  Bros. 2 released in Japan. The Japanese SMB2 was very similar to the  original, not to mention very difficult, and Nintendo was concerned that  these two factors would prevent the game from selling well in America. They  therefore repackaged a game called Doki Doki Panic by giving it a few Mario  elements and released it as Super Mario Bros. 2 in America (this is why the  American SMB2 is so different from any other Mario game). Further  complicating matters, the American SMB2 was released in Japan for the Famicom  Disk System as "Super Mario USA." This is where the alternate versions of  Super Mario All