Peach's floating ability...
You can make Peach float in the air by jumping and holding X or Y. She will start floating after the jump subsides. You can only float once in the air, so if you jump and float, then cut it off with a mid-air jump, you must hit the ground and jump back up again before you can use it again. If you hold Down on the Control Stick and press and hold X or Y, you can float just above the ground.
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