Slim is a Pixl that helps Mario, Princess Peach, Bowser, or Luigi get through gaps in Super Paper Mario, by making them thin as paper. If the hero/heroine does not move, they will become transparent and invincible. The ability was previously provided by a curse from the Black Chest Demon in Paper Mario: The Thousand-Year Door. He can be found in Merlee's Mansion in Chapter 2. In some instances, the player must have Mario "flip" and go through gaps that cannot be seen from the front.
- Catch Card Type: Rare
- Catch Card Description: This sidestepping Pixl can turn you sideways in a snap. Slim likes close calls and hair-raising experiences.