suppermariobroth:

In Super Mario Galaxy 2, there is a way to skip the last part of Rightside Down Galaxy simply by performing a backflip onto the wall surrounding the 2D segment from the small green platform right before the gravity arrows start, as depicted in the top image. Following the wall, a 1-Up Mushroom can be found, showing that this shortcut was intended. Then, simply jump down from the wall towards the Star to collect it, as depicted in the bottom image.
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