Paper Mario : The Thousand-Year Door ( or , as it is nicknamed , Paper Mario 2 ) is a Nintendo GameCube RPG ( role-playing game ) game developed by Nintendo . Paper Mario : The Thousand-Year Door , released in Japan as Paper Mario RPG , is a console role-playing game developed by Intelligent Systems and published by Nintendo for the Nintendo GameCube . The Thousand-Year Door is the fourth game in the Mario RPG series and the second in the Paper Mario series .