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Rotten Mushrooms are purple, skull shaped mushrooms that appear in Super Mario Maker 2. They replace 1-Up Mushrooms when the night mode is activated. Unlike most mushrooms, Rotten Mushrooms actively pursue the player. Due to this and their design, they likely have a negative effect. Their skull-like design and role as an "evil" counterpart to "good" mushrooms makes them comparable to the Poison Mushroom, Zombie Shroom, and Ghoul Shroom.
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