John Gardner makes his story humorous by adding present day items in medieval times. In this story there is a dragon that ravaged the countryside. He tipped over fences, robbed graves, put frogs in people's drinking water, etc. Also the wizard is losing his memory and lost his wizard's book.
John gardner adds humor by making the wizard absent minded and he tried a spell and said “Bimble, Wimble, Cha, Cha, CHOOMPF” and then the queen turned into a rose bush. Now it’s the Cobblers dad turn, the reason he is funny is because he told the 3 sons to recite the poem” Dragon, Dragon, how do you do? I've come from the king to murder you” at the dragon. Last but not least the cobblers youngest son is funny because he had armon “twice