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Blue Bananas are items used in Donkey Kong 64. Here, there are two varieties. One is Lanky Kong's equivalent of an ordinary banana along with bunch varients. The second variety is found only in multiplayer battle mode. When a Kong collects the banana, all the other players are encased in a thick, blue, gelatinous goop. This gives the player who used the Blue Banana an advantage until the others break free.
Blue Bananas resemble unripened Blue Java bananas.