Attack of the Fanboy | How to Unlock Poison Mushroom in Course Creator Super Mario Maker 2 @FanboyAttack | Uploaded 5 years ago | Updated 4 hours ago
To unlock the Poison Mushroom you need to switch your course to night mode by using the Angry Sun. Poison Mushroom or Rotten Mushroom can only be used in the standard game styles for Super Mario Bros, Super Mario Bros. 3, Super Mario World, and Super Mario Bros. U. This cannot be used in Super Mario 3D World.

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