The Fourth dimension is the dimension that Dimentio went to, followed by Mario and friends, in Into the Fourth Dimension. It is home to the Dimension Stars, Power Stars that are purple and can give the person who collects them power to rule, and possibly, destroy dimensions. It is also home too many 4D counterparts to count, such as Quario, Fourigi, QuarioQuario54321, Starman4, QuarioGame4444, FourigiFourigi09876, FourigiFan54321, and Rosey.
- Into the Fourth Dimension was first introduced and known as "4D 2012" in a teaser trailer.
- An early name for Into the Fourth Dimension that MarioMario54321 came up with is Mario's Four-Dimensional Adventure.
- Into the Fourth Dimension was originally going to be in Super Mario 64 and have retextured levels of it like many of MarioMario54321's previous movies, until Skelux made a ROM hack called Super Mario Star Road, which inspired MarioMario54321 to make the movie there instead in order to give fans something new.
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