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In Mario Kart Arcade GP, the Shell Body is one of Bowser's special items. It is functionally identical to the Star, but it also grants the cosmetic change of turning Bowser's kart into the Shell Body temporarily. The Shell Body reverts back to a standard kart after the item's effects wear off. A variant of the item known as the Shell Body+ exists. This variant extends the duration of the invincibility.
In Mario Kart Arcade GP 2, the Shell Body is an unlockable special kart for Bowser. It has high speed and weight but abysmal acceleration. The aforementioned Shell Body item has been removed, as all characters now use the Star as their invincibility item.
Mario Kart Arcade GP 2