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Red Blocks, or red blocks, are special blocks that appear in New Super Mario Bros., New Super Mario Bros. Wii, and Super Mario Run. They start out as Dotted-Line Blocks, but after hitting a ! Switch, they become solid. In New Super Mario Bros., this effect is temporary, and the switches hit are reusable; in New Super Mario Bros. Wii, they are instead activated and deactivated by giant ! Switches on the World 3 map. In this game, they only appear in World 3-4 and World 3-5, and must be activated in order to reach the main Goal Pole of the former and the Red Flagpole of the latter (in the Prima guide, in World 3-4, the exit after the switch was activated was mistakenly labeled a secret exit, and the exit accessible without the switch activated was mistakenly labeled the main exit with a black flag); the switch is only accessible after the other exits to those levels are found. In Super Mario Run, they work as they did in New Super Mario Bros. They appear prominently in Red Block Run, but they can also be found in other courses, such as Switch Ghost House.