Paper Mario: The Thousand-Year Door

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Paper Mario: The Thousand-Year Door, released in Japan as Paper Mario RPG (ペーパーマリオRPG, Pēpā Mario Ārupījī), is a role-playing video game developed by Intelligent Systems and published by Nintendo for the Nintendo GameCube. It is the sequel to Paper Mario and uses the same gameplay and visual style, but with improved visuals, and is also the predecessor of the Wii game, Super Paper Mario. It frequently plays on the "paper" aspect of the universe and its characters, in a fourth-wall breach.

[edit] In Super Smash Bros Brawl

There are many Stickers that hail from the Paper Mario series, such as Rawk Hawk, a sub-boss from the third chapter. Goombella, Mario's first partner, also appears in Brawl as a trophy.