The size change super jump is a glitch in Super Smash Bros. Brawl. This glitch allows certain characters to perform a superjump. It is caused by a character changing size during a special move that provides significant momentum (commonly an up special move).
The glitch can easily be caused by using an applicable up special move into a Super Mushroom or Poison Mushroom; other causes include being hit by Lightning or having one's size returned to normal. The character will fly into the air until they hit a ceiling, at which time they will "float" there for several seconds. If no solid platforms are in the way, they will go above the upper blast line, but not be KO'd or put in helpless.
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