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From Unmariowiki

Paper Mario 2 is the sequal to Paper Mario. After 40 years, George W. Bush finally comes out of the bathroom, and gets mad becuse the Mario's escaped. Bush goes on a rampage, and destroys the city. The Mario's, now in Texas, heard about it and knew it was their destiny to rescue the city.

At the end of the game, the Mario's all get squished and die.