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Wall Faces, also referred to as Wall Masks, are obstacles in Mario & Luigi: Superstar Saga. They are encountered at Chucklehuck Woods, Woohoo Hooniversity, and Joke's End, with each location changing the Wall Face's appearance. When a nearby Pressure Plate is stepped on, the Wall Face opens its eyes and mouth to shoot either a fireball (at Chucklehuck Woods and Joke's End) or a lightning bolt (at Woohoo Hooniversity). If Mario and Luigi are standing on it, they are hit by the blast and sent flying back. If Luigi steps on the Pressure Plate while inside a Barrel (achieved with Luigi Dunk), the blast is rebounded. If the Wall Face launches a fireball, the rebound destroys it and usually opens a door in the process. If it launches a lightning bolt, it bounces perpendicular to the Wall Face.