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The Mystery Mushroom is a power-up that appears in Super Mario Maker. It resembles the sprite of a Super Mushroom from Super Mario Bros. with a question mark printed on its cap. If Mario touches one, he will transform into Costume Mario and take the form of one of various costumes, most of which are based on non-Mario Nintendo characters. The costumes can be unlocked by doing one of the following:
Upon touching one while playing, Mario will take the appearance of the 8-bit sprite himself. It has the same effect as an ordinary Super Mushroom as it grants Mario an extra hit point and he can break Brick Blocks, except it maintains or shrinks him down to (depending on his current state) Small Mario's size.
The Mystery Mushroom is similar to the character caps in Super Mario 64 DS, which also allowed Mario to transform into other characters (and vice-versa). However, while a cap-wearing Mario kept his voice and gained the new character's abilities, Costume Mario keeps Super Mario's abilities while gaining the character's voice or sound effects in most cases.
Mystery Mushrooms have been removed from Super Mario Maker for Nintendo 3DS, although a glitch that involves a Big Magikoopa can make them appear in-game. When collected, they turn Mario into Small Mario, but he also has the ability to break blocks, which Small Mario normally can't do and gives Mario another hit from enemies, as well as showing a different sprite when the player holds down on or .
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