Giant's Body is the penultimate level from Alex Kidd: The Lost Stars.
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This level takes place inside of a giant monster's digestive system. It is the hardest level in the game, with moving bone walls, pools of acidic bile which the player must cross on disintegrating platforms, water dropping from the ceiling and floating blobs blocking the path. The stage is much easier in the SMS version, with most of the obstacles being easier to cross through or having been removed outright.