The Bitlands

The Bitlands is an extremely pixelated (to the point of it being named after such) dimension located beyond the yellow door in Super Paper Mario. It contains several references to other Mario games (most notably the previous two Paper Mario games).

In Chapter 3-1, Tippi is kidnapped by a geeky chameleon named Francis. She is then taken to his fort far away, across the Tile Pool and past the Dotwood Tree. In The Bitlands itself, Mario and Princess Peach discover that Bowser made a makeshift fort there. After a battle against the King of the Koopas, Bowser joins Mario's party, but he is still reluctant about it.

The Bitlands is notable for a humorous instance in which a Koopa Troopa, upon seeing Mario or Peach, races to the right of the screen and hits a ? Block, receives a Mega Star, and becomes Mega Koopa, being largely identical to any other character under the effects of a Mega Star.

Stages in The Bitlands

 * Chapter 3-1: When Geeks Attack (The Bitlands)
 * Chapter 3-2: Bloops Ahoy (The Tile Pool)
 * Chapter 3-3: Up, Up, and a Tree (The Dotwood Tree)
 * Chapter 3-4: The Battle of Fort Francis (Fort Francis)

References to Other Mario Games
The Bitlands (especially Chapter 3-4) holds many references and similarities to older Mario games or other Nintendo-related things. These include:
 * Francis has a Famicom (a Japanese NES), an SNES, a Virtual Boy, an N64, a GameCube, a Game Boy, and (if the player switches to 3-D) a Wii.
 * Francis has a huge amount of posters showing Lady Bow and Bootler (this marks Lady Bow's second cameo appearance in Super Paper Mario), Petuni, Princess Peach, and other, less identifiable characters.
 * Mega Koopa is identical to a Koopa Troopa from Super Mario Bros. on the NES. They are also huge, a possible reference to the Gargantua Koopa Troopa from Super Mario Bros. 3, and it is also a reference to the Mega Goomba from New Super Mario Bros.; a regular Goomba enemy that grabs a Mega Mushroom and gets big.
 * A Blooper is a mini-boss in the Tile Pool; Bloopers have had at least a mini-boss role in every Paper Mario game to date
 * Bowser declares that there will be no more sequels; many Mario games have at least one sequel, and Bowser gets defeated in both Paper Mario sequels.
 * Francis is a big fan of Mario reference-filled TV shows, one of which involves Tubba Blubba (making every Paper Mario game to date have a giant Clubba at least mentioned in their corresponding Chapter 3s), another involving X-Nauts, the last of which involving Sir Grodus.
 * The underground cavern in 3-1 is an almost exact replica of World 1-2 in the original Super Mario Bros. The only differences are some of the power-ups have been changed, and a small area has been removed.
 * The overworld music has several interludes in which segments of the Super Mario Bros. theme may be heard clearly.
 * The player must take the second pipe in the Warp Zone look-alike area to continue the sub-chapter, which may be a reference to Super Mario Bros. when Mario or Luigi must take the second pipe in the Warp Zone to go to World 3, which is the world the Bitlands is.

Trivia
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 * The Bitlands is notable for being the only stage in all of Paper Mario history in which Koopa Troopas without sunglasses and spiked necklaces can be fought. This is because, according to Super Paper Mario, Koopa Troopas without these features work for Bowser while those with them had previously been hypnotized by Nastasia and therefore forced to join Count Bleck's Army; past Paper Mario games stated that Koopas without sunglasses and spiked necklaces are friendly while those wearing them were the ones who worked for Bowser. The overall reason for Bowser's Koopas combating Mario and friends, though, was simply because the group was nearing one of Bowser's castles.
 * According to The InterNed, the overworld music of The Bitlands is titled "The Open Plane", and the music in the underground area beneath the two red pipes is titled "Nostalgic Underground", due to it being an altered version of the classic underground theme from Super Mario Bros.
 * The Bitlands, along with Castle Bleck, is the only chapter where there is at least one boss in each section; Bowser in 3-1, who joins Mario's party after being defeated, Big Blooper in 3-2, Dimentio in 3-3, and Francis in 3-4.
 * The Bitlands is one of the three areas to not be destroyed when Dimentio took control of the Chaos Heart. (With the other two being the Underwhere and the Overthere.)
 * When Mario comes to a part of Chapter 3-1 with all the colorful blocks, if he flips, he can see they are really simple poses of block statues.