Super Mario Bros.: The Lost Levels
Super Mario Bros.: The Lost Levels
According to then Nintendo of America CEO Howard Lincolin, the game was not released overseas because it was too challenging and too much like the original to sell well. In order to prevent the early series from being associated with frustration and staleness, they instead adapted the Japan only game Doki Doki Panic. They released it as Super Mario Bros. 2 for the West.
Contributed by CuriousUserX90
According to an interview with Shigeru Miyamoto in Family Computer Magazine, World 9 of Super Mario Bros.: The Lost Levels, which is only accessible by playing the entire game without using Warp Zones, is based on a glitch in the original Super Mario Bros, which could allow the player to access 256 extra worlds.
Contributed by game4brains