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World D is the fifth and final secret world that was featured in the game Super Mario Bros.: The Lost Levels. Like the other secret worlds, it was left unused in Super Mario Bros. Deluxe. When Bowser is defeated at the end of World D-4, Princess Toadstool is saved, and, as such, Mario and Luigi beat the game.
||A level similar to World 8-1. In the original FDS version, it is a snowy level, but in the SNES remake, its a grassy level.
||This level includes several upside down Piranha Plants.
||A level which has a brick wall in the background similar to World 8-3's. In Super Mario All-Stars the wall is gone so the brick blocks are replaced with hidden blocks.
||A castle which starts out like World 8-4, but there are only 5 Fire Bars that Mario or Luigi needs to avoid.
Super Mario Bros.: The Lost Levels
Super Mario All-Stars