<P> The Knight was, in fact, played by two actors: John Cleese is in the Knight's armour until he is down to one leg . The Knight is then played by a real one - legged man, a local by the name of Richard Burton, a blacksmith who lived near the film shoot (not to be confused with Richard Burton, the Welsh actor of the same name), because, according to the DVD commentary, Cleese could not balance well on one leg . After the Knight's remaining leg is cut off, the quadruple - amputee that remains is again Cleese . Cleese still boasts that he had Richard Burton as his stunt double . </P> <P> In the musical Spamalot, the scene with the Black Knight was the most difficult to play on stage, according to Eric Idle . Penn & Teller created the illusion for the musical . </P>

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