Super Paper Mario

Super Paper Mario is an unreleased Paper Mario game that takes place after the Thousand-Year Door adventure.

The game features a gameplay upgrade from previous Paper Mario games in that the player can switch between 2D and 3D perspectives. This feature is used to get around the game, since one perspective may not see certain secrets that the other reveals.

Story
Count Bleck raids Mushroom Kingdom's palace and kidnaps Princess Peach. Mario and Luigi, thinking it to be Bowser's work, once again set out to save Mario's beloved. As Mario and Luigi confront Bowser, Count Bleck sucks Bowser's forces and Luigi into another world. With the help of a special butterfly, Mario teleports to Flipside, a place made up of people who are against Count Bleck. Count Bleck wields a powerful weapon called the Dark Prognosticus, which he used to create the void that sucked up Bowser. Bleck forces Bowser and Peach into wedlock and in doing so, the union of the two is said to summon the "Chaos Heart, the consumer of worlds."