The Playlist brings an interesting list of improbable facts about The Empire Strikes Back, such as:
3. John Lithgow once played Yoda, who started out as a frog monster named Buffy.
While most of the cast were simply returning from "Star Wars," there were a couple of key additions. First and foremost among them: Yoda, the wizened, diminuitive Jedi master who teaches Luke in the ways of the Force, who would grow to become one of the most iconic and beloved characters in the whole franchise. But we could have ended up with a very different look for the character. In J.W. Rinzler's book "The Making of Star Wars: The Empire Strikes Back," it's noted that in Lucas' earliest outlines, the character was a "three or four thousand" year old supernatural being called either Bunden Debannen or, believe it or not, Buffy. Later, by the time of Brackett's draft, the character had become 'Minch Yoda,' a small frog-like creature. Even then, the design wasn't nailed down until quite late: the Marvelcomics adaptation, at least in the paperback book form, depicted Yoda as a pink-skinned creature with long white hair, reflecting the look of the character at the time work on the adaptation got underway. The final look was inspired famously by Albert Einstein, but also by director Irvin Kershner and the film's make-up artist Stuart Freeborn. And while, Frank Oz is famously the voice and main puppeteer of the character, future Oscar-nominee John Lithgow would also get a chance: the actor voiced Yoda in a 1983 radio adaptation which included most of the original cast (you can hear an extract below). The film's other major new character was Lando Calrissian, which was originally offered to "Alien" star Yaphet Kotto, who turned it down for fear he might become too associated with the role.
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