Outer Space is the setting of Chapter 4 in Super Paper Mario. Chapter 4 may not take place in the outer space above the Mushroom Kingdom, but rather that of another dimension. It was once the location of the Squirpia kingdom.
In Chapter 4-1, the heroes meet Squirps, a mysterious alien creature who functions as a ray gun for stages 4-1 and 4-3, as well as in the battle against Brobot. A large portion of this chapter involves a Squarp Hole maze, which requires the player to remember which Holes are linked to which in order to progress.
Chapter 4-1: Into Outer Space
Upon entering the green door at the top of Flipside Tower, Mario and co. find themselves in space and realize that they cannot breathe. Tippi warps them all back to Flipside, where they tell Merlon about their problem. He explains that a helmet would allow them to breathe, but he gave away the only one he had to a little boy, who the heroes discover to be Pook. Pook is using the helmet as a fishbowl for his pet, Captain Gills, who is growing too large for it. Pook gives the heroes the fishbowl and asks them to release Captain Gills. After placing the fish in a canal in Flipside's basement, the heroes return to space and put on the helmet, allowing them to explore the new world.
The heroes follow an SOS to a space capsule, containing a small alien named Squirps, who knows of the heroes and their mission to gather the Pure Hearts. While Tippi is suspicious of Squirps, Mario accepts the alien's help. Squirp opens a warp called a Squarp Hole, which he says will take the group directly the Pure Heart. However, the warp is far off target and the heroes are forced to navigate a maze of Squarp Holes.
The level's lack of gravity allows the player to move anywhere they want using the D-Pad. As they cannot stomp enemies in this state, they may instead use Squirps' Squirt Beam to attack enemies. The level is mostly empty, aside from enemies and stationary asteroids. If the player flips near a certain asteroid, they will find a Squarp Hole behind it. This Squarp Hole will lead the heroes to the background, where they can go through a pipe on another asteroid to find a room full of coins. There are many Squarp Holes in the level, with the correct warp usually being the one farthest away from where the heroes started from.
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