Wailord is described in its Pokédex entries as being 47 feet 7 inches tall (14.5m) on its stomach and 877.4lbs (398.0kg). It seems to me like it weighs way too little for its size. How dense would Wailord have to be if it were real? How much would a one foot by one foot cube weigh if it were cut from a Wailord?
closed as off topic by dmckee♦ Aug 17 '12 at 13:36
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Comparison with a real-world example indicates you're right in thinking this thing is likely too light for its size.
But then again, it might have an anti-gravity drive inside it.