Paper Mode

Paper Mode is one of Mario's transformations seen in Paper Mario: The Thousand-Year Door, and the second one obtained. Similarly to his other origami-themed forms, it is granted to him in the form of a "curse" from one of the Black Chest Demons in Hooktail Castle.

Paper Mode allows Mario (and his party) to turn sideways, using his paper-thin body to fit through small gaps. It can be activated by holding, with Mario returning to normal once is released. While in Paper Mode, Mario moves more slowly, and cannot use his hammer, Spin Jump, Spring Jump, or use partner abilities.

The Paper Game, a minigame in the Pianta Parlor, utilizes this move.

In Super Paper Mario, the Pixl Slim has a similar ability.