Sergio AragonÃ s ( 1937 - ) is a popular cartoonist . Sergio AragonÃ s Domenech ( born September 6 , 1937 , San Mateo , CastellÃ n , Spain ) is a cartoonist and writer best known for his contributions to Mad Magazine and creator of the comic book Groo the Wanderer . Among his peers and fans , AragonÃ s is widely regarded as `` the world 's fastest cartoonist . ''