The chocobo whistle is currently incomplete and as such, does nothing when clicking the right or left mouse button.
It is crafted with a single chocobo feather, and an ingot of gold. However, the use for the whistle is still unknown.(edited by Leonhaert_ : it is supposedly meant to call back the last chocobo you were riding to you so say if you're going somewhere dangerous and dont wanna bring you're chocobo leave it a little away and when you get out of the area use the whistle to call the chocobo to you)
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