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From the images of 4F and 3F of Sky Pillar, it looks like the left-most cracked tile actually lands you right where you want to go on the third floor. I've checked several times and I'm pretty sure that you do not actually need the mach bike.
I'm not comfortable with changing that since I haven't actually played Emerald, but the walkthrough seems to be wrong on that. Nixitur (talk) 22:39, 3 April 2014 (UTC)

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