Retro Goofy is a form Goofy takes when he visits Timeless River with Sora and Donald in Kingdom Hearts II. When Goofy and his friends are in this unique world, they are all converted into the older versions of their earlier cartoons.
Kingdom Hearts II
Two Weeks Vacation (1952)
Captain of the Royal Knights.
To save Disney Castle, Goofy went through a doorway Merlin conjured up into a black-and-white world that seemed strangely familiar.
In his Retro Form, Goofy transforms into a monochrome version of his original appearance in the original Disney cartoons. Goofy's physical structure changes very little In this form, though he has a noticeable Adam's Apple and a short tail.
He retains his white gloves, shoes, and hat, though his shoes are much simpler in design and his hat is a black and white version of the one he normally wears in Disney media, as opposed to his usual Kingdom Hearts one. The only other article of clothing Goofy wears in this form is a single-button vest.
This form is largely based on Goofy's original appearance, at that time he was known as "Dippy Dawg", in the 1932 cartoon Mickey's Revue. Dippy Dawg was portrayed as an annoying, elderly member of the audience and a running gag of the short. Retro Goofy is primarily a younger version of said character. This younger version first appeared in Goofy's next cartoon, The Whoopee Party.