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Giant Bananas are larger variants of regular Bananas that occasionally appear as items.
Mario Kart: Double Dash!!
In Mario Kart: Double Dash!!, it is a special item that Donkey Kong and Diddy Kong, (and Petey Piranha and King Boo, due to their ability to have any special item) can obtain in Double Dash. Once a driver makes contact with the Giant Banana Peel, it not only makes the driver spin out for a longer duration for a regular Banana, but it also explodes and leaves three regular Bananas on the ground.
Mario Strikers Charged
In Mario Strikers Charged, the Giant Banana is one of the many items used by the players. Whoever uses the item drops it behind them, which hits anyone who runs into it. It is similar to the smaller Banana, though the Giant Banana has a larger range and can hit more than one player. Unlike the smaller bananas, the Giant Banana item only deploys one banana, not multiple bananas.