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A One-Way Wall is an object found in Super Mario Maker, Super Mario Maker for Nintendo 3DS, and Super Mario Maker 2. They are available in all game styles except Super Mario Maker 2's Super Mario 3D World style. Similar to the Flippers from the Yoshi's Island games, once Mario passes through the gate, he cannot go back through it from the other side. When pointed upwards, One-Way Walls act similarly to semisolid platforms and can be destroyed in the Super Mario Bros. and Super Mario Bros. 3 styles by ground pounding them with a big Goomba's Shoe. A One-Way Wall is the size of four regular blocks, and the arrow imprinted on it indicates the direction in which Mario can enter.
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